9.4: Biases in Survey Research
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Despite all of its strengths and advantages, survey research is often tainted with systematic biases that may invalidate some of the inferences derived from such surveys. Five such biases are the non-response bias, sampling bias, social desirability bias, recall bias, and common method bias.
Non-response bias. Survey research is generally notorious for its low response rates. A response rate of 15-20 per cent is typical in a postal survey, even after two or three reminders. If the majority of the targeted respondents fail to respond to a survey, this may indicate a systematic reason for the low response rate, which may in turn raise questions about the validity of the study’s results. For instance, dissatisfied customers tend to be more vocal about their experience than satisfied customers, and are therefore more likely to respond to questionnaire surveys or interview requests than satisfied customers. Hence, any respondent sample is likely to have a higher proportion of dissatisfied customers than the underlying population from which it is drawn. In this instance, not only will the results lack generalisability, but the observed outcomes may also be an artefact of the biased sample. Several strategies may be employed to improve response rates:
Advance notification: Sending a short letter to the targeted respondents soliciting their participation in an upcoming survey can prepare them in advance and improve their propensity to respond. The letter should state the purpose and importance of the study, mode of data collection (e.g., via a phone call, a survey form in the mail, etc.), and appreciation for their co-operation. A variation of this technique may be to ask the respondent to return a prepaid postcard indicating whether or not they are willing to participate in the study.
Relevance of content: People are more likely to respond to surveys examining issues of relevance or importance to them.
Respondent-friendly questionnaire: Shorter survey questionnaires tend to elicit higher response rates than longer questionnaires. Furthermore, questions that are clear, non-offensive, and easy to respond tend to attract higher response rates.
Endorsement: For organizational surveys, it helps to gain endorsement from a senior executive attesting to the importance of the study to the organization. Such endorsement can be in the form of a cover letter or a letter of introduction, which can improve the researcher’s credibility in the eyes of the respondents.
Follow-up requests: Multiple follow-up requests may coax some non-respondents to respond, even if their responses are late.
Interviewer training: Response rates for interviews can be improved with skilled interviewers trained in how to request interviews, use computerised dialing techniques to identify potential respondents, and schedule call-backs for respondents who could not be reached.
Incentives : Incentives in the form of cash or gift cards, giveaways such as pens or stress balls, entry into a lottery, draw or contest, discount coupons, promise of contribution to charity, and so forth may increase response rates.
Non-monetary incentives: Businesses, in particular, are more prone to respond to non-monetary incentives than financial incentives. An example of such a non-monetary incentive is a benchmarking report comparing the business’s individual response against the aggregate of all responses to a survey.
Confidentiality and privacy: Finally, assurances that respondents’ private data or responses will not fall into the hands of any third party may help improve response rates
Sampling bias. Telephone surveys conducted by calling a random sample of publicly available telephone numbers will systematically exclude people with unlisted telephone numbers, mobile phone numbers, and people who are unable to answer the phone when the survey is being conducted—for instance, if they are at work—and will include a disproportionate number of respondents who have landline telephone services with listed phone numbers and people who are home during the day, such as the unemployed, the disabled, and the elderly. Likewise, online surveys tend to include a disproportionate number of students and younger people who are constantly on the Internet, and systematically exclude people with limited or no access to computers or the Internet, such as the poor and the elderly. Similarly, questionnaire surveys tend to exclude children and the illiterate, who are unable to read, understand, or meaningfully respond to the questionnaire. A different kind of sampling bias relates to sampling the wrong population, such as asking teachers (or parents) about their students’ (or children’s) academic learning, or asking CEOs about operational details in their company. Such biases make the respondent sample unrepresentative of the intended population and hurt generalisability claims about inferences drawn from the biased sample.
Social desirability bias . Many respondents tend to avoid negative opinions or embarrassing comments about themselves, their employers, family, or friends. With negative questions such as, ‘Do you think that your project team is dysfunctional?’, ‘Is there a lot of office politics in your workplace?’, ‘Or have you ever illegally downloaded music files from the Internet?’, the researcher may not get truthful responses. This tendency among respondents to ‘spin the truth’ in order to portray themselves in a socially desirable manner is called the ‘social desirability bias’, which hurts the validity of responses obtained from survey research. There is practically no way of overcoming the social desirability bias in a questionnaire survey, but in an interview setting, an astute interviewer may be able to spot inconsistent answers and ask probing questions or use personal observations to supplement respondents’ comments.
Recall bias. Responses to survey questions often depend on subjects’ motivation, memory, and ability to respond. Particularly when dealing with events that happened in the distant past, respondents may not adequately remember their own motivations or behaviours, or perhaps their memory of such events may have evolved with time and no longer be retrievable. For instance, if a respondent is asked to describe his/her utilization of computer technology one year ago, or even memorable childhood events like birthdays, their response may not be accurate due to difficulties with recall. One possible way of overcoming the recall bias is by anchoring the respondent’s memory in specific events as they happened, rather than asking them to recall their perceptions and motivations from memory.
Common method bias. Common method bias refers to the amount of spurious covariance shared between independent and dependent variables that are measured at the same point in time, such as in a cross-sectional survey, using the same instrument, such as a questionnaire. In such cases, the phenomenon under investigation may not be adequately separated from measurement artefacts. Standard statistical tests are available to test for common method bias, such as Harmon’s single-factor test (Podsakoff, MacKenzie, Lee & Podsakoff, 2003), Lindell and Whitney’s (2001) market variable technique, and so forth. This bias can potentially be avoided if the independent and dependent variables are measured at different points in time using a longitudinal survey design, or if these variables are measured using different methods, such as computerised recording of dependent variable versus questionnaire-based self-rating of independent variables.


17.1G: Fibrous Skeleton of the Heart
The cardiac skeleton, also known the heart’s fibrous skeleton, consists of dense connective tissue in the heart that separates the atria from the ventricles.
- Describe composition and function of the heart’s fibrous skeleton
Key Points
- The cardiac skeleton consists of four bands of dense connective tissue, called fibrous rings, that surround the base of the pulmonary trunk, aorta, and mitral and tricuspid valves.
- The heart ‘s fibrous skeleton stops the flow of electrical currents between the chambers of the heart so that it only flows through the atrioventricular (AV) bundle. This causes a delay in depolarization so that the ventricles contract after they fill with blood.
- The AV bundle is a bundle of electrically-connected cardiomyocytes that transmit impulses from the AV node to the apex of the heart. It is located in the center of the cardiac skeleton.
- The cardiac skeleton consists mainly of the protein collagen, a glycoprotein found in all connective tissues.
Key Terms
- collagen : A glycoprotein that forms elongated fibers, usually found in the extracellular matrix of connective tissue.
- fibrous rings : Four dense bands of tough elastic tissue that encircle the bases of the valves of the heart.
The cardiac skeleton, or fibrous skeleton of the heart, is the structure of dense connective tissue that separates the atria from the ventricles. The fibrous skeleton provides critical support for the heart and separates the flow of electrical impulses through the heart.
Fibrous Ring Structure
Fibrous Rings of the Heart : Transverse section of the heart showing the fibrous rings surrounding the valves.
The primary structure of cardiac skeleton consists of four dense bands of tough elastic tissue called fibrous rings that encircle the bases of the heart valves. The fibrous skeleton is composed primarily of collagen, a protein found in every type of connective tissue in the human body. There are four fibrous rings:
- The aortic ring encircles the aortic valve. It provides support for the aortic valve so that it is open, yet does not have backflow.
- The pulmonary ring encircles the pulmonary valve. Similar to the aortic ring, it provides structural support for the pulmonary valve.
- The left fibrous ring encircles the bicuspid valve. This ring is the thickest and strongest of all the fibrous rings due to the thickness of the left ventricle, which requires more structural support than the other chambers of the heart. It also surrounds the coronary arteries and AV node.
- The right fibrous ring encircles the tricuspid valve. It also surrounds the coronary arteries and AV node.
The fibrous skeleton provides a great amount of structural and functional support for the valves of the heart by enabling them to stay open and provides a point of attachment for the valves to the wall of the heart.
Electrical Functions
The fibrous skeleton of the heart acts as an insulator for the flow of electrical current across the heart. It stops the flow of electricity between the different chambers of the heart so that electrical impulses do not flow directly between the atria and ventricles. The sinoatrial (SA) node lies on the top of the heart, while the AV node is located at the center of the fibrous skeleton, the only path by which electricity can flow through the heart.
This electrical separation is essential for cardiac function, because electrical impulses flow from the top of the heart to the bottom of the heart. The separation allows the AV node and AV bundle to delay the wave of depolarization so that the atria can contract and assist in ventricular filling before the ventricles themselves depolarize and contract. Without the fibrous skeleton of the heart, the heart’s ability to pump blood would be considerably less efficient since the ventricles would contract before filled to capacity. The fibrous skeleton of the heart also protects against cardiac arrhythmias.
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6.3: Normal Distributions
By the end of this chapter, the student should be able to:
- Recognize and use the normal probability distribution.
- Recognize and use the standard normal probability distribution.
A special continuous distribution, called normal, is the most common and therefore most important of all the distributions. It is widely used and even more widely abused. Its graph is bell-shaped. You see the bell curve in almost all disciplines. Some of these include psychology, business, economics, the sciences, nursing, and, of course, mathematics. Some of your instructors may use the normal distribution to help determine your grade. Most IQ scores are normally distributed. Often real-estate prices fit a normal distribution. The normal distribution is extremely important, but it cannot be applied to everything in the real world.
In this section, you will study the normal distribution, the standard normal distribution, and applications associated with them. To study normal distributions, we must introduce a normal probability density function and its graph. Normal distributions have two parameters, the mean (\(\mu\)) and the standard deviation (\(\sigma\)). If \(X\) is a quantity to be measured that has a normal distribution with mean (\(\mu\)) and standard deviation (\(\sigma\)), we denote it as \(X\sim N(\mu,\sigma)\) and the probability density function of \(X\) is
\(f(x) = \dfrac{1}{\sigma \cdot \sqrt{2 \cdot \pi}} \cdot e^{\left(-\dfrac{1}{2}\right) \cdot \left(\dfrac{x-\mu}{\sigma}\right)^{2}}\)
As you can see, the probability density function is a rather complicated function. Do not memorize it as it is not necessary. So instead, let's focus on its graph which varies depending on the values of \(\mu\) and \(\sigma\).
Note that the two parameters uniquely determine the shape of the probability density curve, i.e. the center and the spread. The curve is symmetrical about a vertical line drawn through the mean, \(\mu\). In theory, the mean is the same as the median, because the graph is symmetric about \(\mu\). Since the area under the curve must equal one, a change in the standard deviation, \(\sigma\), causes a change in the shape of the curve; the curve becomes fatter or skinnier depending on the change of \(\sigma\). A change in \(\mu\) causes the graph to shift to the left or right. This means there are an infinite number of normal probability distributions. One of special interest is called the standard normal distribution, \(Z \sim N(0, 1)\).
Since normal random variables are continuous random variables, everything that we learned about continuous random variables in the previous section will hold for normal variables as well. For example, one of the most important facts is that the area under the probability density curve is the probability of some event that can be expressed in teh inequality form.
The shaded area in the following graph indicates the area to the left of \(x\). This area is represented by the probability \(P(X < x)\).
How would you represent the area to the left of one in a probability statement?
Answer
\(P(X < 1)\)
Since the \(P(X=x)=0\) for any continuous random variable \(X\) and any value \(x\), we conclude that \(P(X < x)\) is the same as \(P(X \leq x)\) and \(P(X > x)\) is the same as \(P(X \geq x)\) for normal distributions as well.
Is \(P(X < 1)\) equal to \(P(X \leq 1)\)? Why?
Answer
Yes, because they are the same in a continuous distribution: \(P(X = 1) = 0\)
Since the total area under the probability density curve is 1, the area to the right is then \(P(X > x) = 1 – P(X < x)\). Remember, \(P(X < x) =\) Area to the left of the vertical line through \(x\). \(P(X > x) = 1 – P(X < x) =\) Area to the right of the vertical line through \(x\).
Express symbolically the area to the right of three:
Answer
\(1 – P(X < 3)\) or \(P(X > 3)\)
If the area to the right of \(x\) in a normal distribution is 0.543, what is the area to the left of \(x\)?
Answer
\(1 - 0.543 = 0.457\)
Calculations of Probabilities
Normal tables, computers, and calculators are used to provide or calculate the probabilities such as \(P(a < X < b)\), \(P(X < c)\), or \(P(X > c)\) for any variable \(X\) and any values \(a, b, c\). Technology has made the tables virtually obsolete. For that reason, as well as the fact that there are various table formats, we are not including table instructions in this textbook.
There are many online calculators that can be used to compute the probabilities that involve normal and other random variables. For example, you can use this one :
Also, you are encouraged to ask your instructor about which calculator is allowed/recommended for this course.
Use the calculator provided above to verify the following probability statements for \(X \sim N(6, 2)\):
\(P(X<3.5)=0.1056\)
\(P(4.1<X<6.3)=0.3885\)
\(P(X>8.2)=0.1357\)
\(X \sim N(–3, 4)\)
Find the probability that \(X\) is between one and four, i.e. \(P(1<X<4)\).
Answer
0.1186
Recall that the k-th percentile of a dataset is the value such that k% of the data are below this value. In the context of a random variable, the k-th percentile of \(X\) is the value \(x\) such that the probability \(P(X<x)=k/100\).
For \(X\sim N(35,5)\), \(P(X<36)=0.58\). Therefore \(36\) is the 58-th percentile of \(X\). If we were asked to find the 58-th percentile of \(X\) then essentially we are asked to find the value \(x\) such that \(P(X<x)=0.58\). Many online calculators allow to set up such an equation by leaving blank instead of \(x\).
Find the 42-nd percentile for a normal random variable \(X\sim N(\mu=93.8, \sigma=5.8)\).
- Answer
-
92.63
As we indicated above, normal distributions have miryad of applications.
The final exam scores in a statistics class were normally distributed with a mean of 63 and a standard deviation of five.
- Find the probability that a randomly selected student scored more than 65 on the exam.
- Find the probability that a randomly selected student scored less than 85.
- Find the 90 th percentile (that is, find the score \(k\) that has 90% of the scores below k and 10% of the scores above \(k\)).
- Find the 70 th percentile (that is, find the score \(k\) such that 70% of scores are below \(k\) and 30% of the scores are above \(k\)).
Answer
a. Let \(X\) be a score on the final exam. \(X \sim N(63, 5)\), where \(\mu = 63\) and \(\sigma = 5\). Draw a graph. Then, find \(P(x > 65)\).
\(P(X > 65) = 0.3446\nonumber \)
The probability that any student selected at random scores more than 65 is 0.3446.
Answer
b. Draw a graph. Then find \(P(X < 85)\), and shade the graph. Using a computer or calculator, find \(P(X < 85) = 1\). The probability that one student scores less than 85 is approximately one (or 100%).
Answer
c. Find the 90 th percentile. For each problem or part of a problem, draw a new graph. Draw the \(x\)-axis. Shade the area that corresponds to the 90 th percentile.
Let \(k\) be the 90 th percentile. The variable \(k\) is located on the \(x\)-axis. \(P(X < k)\) is the area to the left of \(k\). The 90 th percentile \(k\) separates the exam scores into those that are the same or lower than \(k\) and those that are the same or higher. Ninety percent of the test scores are the same or lower than \(k\), and ten percent are the same or higher. The variable \(k\) is often called a critical value. Using a computer or calculator, \(k = 69.4\)
The 90 th percentile is 69.4. This means that 90% of the test scores fall at or below 69.4 and 10% fall at or above.
Answer
d. Find the 70 th percentile.
Draw a new graph and label it appropriately. The 70 th percentile is 65.6. This means that 70% of the test scores fall at or below 65.5 and 30% fall at or above.
A personal computer is used for office work at home, research, communication, personal finances, education, entertainment, social networking, and a myriad of other things. Suppose that the average number of hours a household personal computer is used for entertainment is two hours per day. Assume the times for entertainment are normally distributed and the standard deviation for the times is half an hour.
- Find the probability that a household personal computer is used for entertainment between 1.8 and 2.75 hours per day.
- Find the maximum number of hours per day that the bottom quartile of households uses a personal computer for entertainment.
- Answer
-
a. Let \(X =\) the amount of time (in hours) a household personal computer is used for entertainment. \(X \sim N(2, 0.5)\) where \(\mu = 2\) and \(\sigma = 0.5\).
Find \(P(1.8 < X < 2.75)\).
The probability for which you are looking is the area between \(x = 1.8\) and \(x = 2.75\). \(P(1.8 < X < 2.75) = 0.5886\)
The probability that a household personal computer is used between 1.8 and 2.75 hours per day for entertainment is 0.5886.
b. To find the maximum number of hours per day that the bottom quartile of households uses a personal computer for entertainment, find the 25 th percentile, \(k\), where \(P(X < k) = 0.25\).
The maximum number of hours per day that the bottom quartile of households uses a personal computer for entertainment is 1.66 hours.
There are approximately one billion smartphone users in the world today. In the United States the ages 13 to 55+ of smartphone users approximately follow a normal distribution with approximate mean and standard deviation of 36.9 years and 13.9 years, respectively.
a. Determine the probability that a random smartphone user in the age range 13 to 55+ is between 23 and 64.7 years old.
b. Determine the probability that a randomly selected smartphone user in the age range 13 to 55+ is at most 50.8 years old.
c. Find the 80 th percentile of this distribution, and interpret it in a complete sentence.
- Answer
-
a. \(0.8186\)
b. \(0.8413\)
c. T he 80 th percentile is 48.6 years meaning 80% of the smartphone users in the age range 13 – 55+ are 48.6 years old or less.
The life of Sunshine CD players is normally distributed with a mean of 4.1 years and a standard deviation of 1.3 years. We are interested in the length of time a CD player lasts.
a. A CD player is guaranteed for three years. Find the probability that a CD player will break down during the guarantee period.
b. Find the probability that a CD player will last between 2.8 and six years.
c. Find the 70 th percentile of the distribution for the time a CD player lasts.
Answer
- 19.87%
- 76.94%
- 4.78 years.


2.10: Observing the Sky - The Birth of Astronomy (Exercise)
For Further Exploration
Articles
Ancient Astronomy
Gingerich, O. “From Aristarchus to Copernicus.” Sky & Telescope (November 1983): 410.
Gingerich, O. “Islamic Astronomy.” Scientific American (April 1986): 74.
Astronomy and Astrology
Fraknoi, A. “Your Astrology Defense Kit.” Sky & Telescope (August 1989): 146.
Copernicus and Galileo
Gingerich, O. “Galileo and the Phases of Venus.” Sky & Telescope (December 1984): 520.
Gingerich, O. “How Galileo Changed the Rules of Science.” Sky & Telescope (March 1993): 32.
Maran, S., and Marschall, L. “The Moon, the Telescope, and the Birth of the Modern World.” Sky & Telescope (February 2009): 28.
Sobel, D. “The Heretic’s Daughter: A Startling Correspondence Reveals a New Portrait of Galileo.” The New Yorker (September 13, 1999): 52.
Brahe and Kepler
Christianson, G. “The Celestial Palace of Tycho Brahe.” Scientific American (February 1961): 118.
Gingerich, O. “Johannes Kepler and the Rudolphine Tables.” Sky & Telescope (December 1971): 328. Brief article on Kepler’s work.
Wilson, C. “How Did Kepler Discover His First Two Laws?” Scientific American (March 1972): 92.
Newton
Christianson, G. “Newton’s Principia : A Retrospective.” Sky & Telescope (July 1987): 18.
Cohen, I. “Newton’s Discovery of Gravity.” Scientific American (March 1981): 166.
Gingerich, O. “Newton, Halley, and the Comet.” Sky & Telescope (March 1986): 230.
Sullivant, R. “When the Apple Falls.” Astronomy (April 1998): 55. Brief overview.
The Discovery of Neptune
Sheehan, W., et al. “The Case of the Pilfered Planet: Did the British Steal Neptune?” Scientific American (December 2004): 92.
Websites
Ancient Astronomy
Aristarchos of Samos: http://adsabs.harvard.edu//full/seri...00029.000.html . By Dr. Alan Batten.
Claudius Ptolemy: www-history.mcs.st-and.ac.uk/...s/Ptolemy.html. An interesting biography.
Hipparchus of Rhodes: www-history.mcs.st-andrews.ac...ipparchus.html. An interesting biography.
Astronomy and Astrology
Astrology and Science: http://www.astrology-and-science.com/hpage.htm . The best site for a serious examination of the issues with astrology and the research on whether it works.
Real Romance in the Stars: http://www.independent.co.uk/voices/...s-1527970.html . 1995 newspaper commentary attacking astrology.
Copernicus and Galileo
Galileo Galilei: www-history.mcs.st-andrews.ac...s/Galileo.html. A good biography with additional links.
Galileo Project: http://galileo.rice.edu/ . Rice University’s repository of information on Galileo.
Nicolaus Copernicus: www-groups.dcs.st-and.ac.uk/~...opernicus.html. A biography including links to photos about his life.
Brahe and Kepler
Johannes Kepler: His Life, His Laws, and Time: kepler.nasa.gov/Mission/JohannesKepler/. From NASA’s Kepler mission.
Johannes Kepler: http://www.britannica.com/biography/Johannes-Kepler . Encyclopedia Britannica article.
Johannes Kepler: www-history.mcs.st-andrews.ac...es/Kepler.html. MacTutor article with additional links.
Noble Dane: Images of Tycho Brahe: http://www.mhs.ox.ac.uk/tycho/index.htm . A virtual museum exhibit from Oxford.
Newton
Sir Isaac Newton: www-groups.dcs.st-and.ac.uk/~...es/Newton.html. MacTutor article with additional links.
Sir Isaac Newton: http://www.luminarium.org/sevenlit/n.../newtonbio.htm . Newton Biography at the Luminarium.
The Discovery of Neptune
Adams, Airy, and the Discovery of Neptune: http://www.mikeoates.org/lassell/adams-airy.htm . A defense of Airy’s role by historian Alan Chapman.
Mathematical Discovery of Planets: www-groups.dcs.st-and.ac.uk/~...and_Pluto.html. MacTutor article.
Videos
Astronomy and Astrology
Astrology Debunked: https://www.youtube.com/watch?v=y84HX2pMo5U . A compilation of scientists and magicians commenting skeptically on astrology (9:09).
Copernicus and Galileo
Galileo: http://www.biography.com/people/galileo-9305220 . A brief biography (2:51).
Nicolaus Copernicus: http://www.biography.com/people/nico...rnicus-9256984 . An overview of his life and work (2:41).
Brahe and Kepler
“Harmony of the Worlds.” This third episode of Carl Sagan’s TV series Cosmos focuses on Kepler and his life and work.
Newton
Beyond the Big Bang: Sir Isaac Newton’s Law of Gravity: http://www.history.com/topics/enligh...law-of-gravity . From the History Channel (4:35).
Sir Isaac Newton versus Bill Nye: Epic Rap Battles of History: https://www.youtube.com/watch?v=8yis7GzlXNM . (2:47).
The Discovery of Neptune
Richard Feynman: On the Discovery of Neptune: https://www.youtube.com/watch?v=FgXQffVgZRs . A brief black-and-white Caltech lecture (4:33).
Review Questions
- Explain, according to both geocentric and heliocentric cosmologies, why we see retrograde motion of the planets.
- In what ways did the work of Copernicus and Galileo differ from the views of the ancient Greeks and of their contemporaries?
- What were four of Galileo’s discoveries that were important to astronomy?
- The Sun was once thought to be a planet. Explain why.
- Why did Pythagoras believe that Earth should be spherical?
- How did Aristotle deduce that the Sun is farther away from Earth than the Moon?
- What are two ways in which Aristotle deduced that Earth is spherical?
- How did Hipparchus discover the wobble of Earth’s axis, known as precession ?
- Why did Ptolemy have to introduce multiple circles of motion for the planets instead of a single, simple circle to represent the planet’s motion around the Earth?
- Why did Copernicus want to develop a completely new system for predicting planetary positions? Provide two reasons.
- What two factors made it difficult, at first, for astronomers to choose between the Copernican heliocentric model and the Ptolemaic geocentric model?
- What phases would Venus show if the geocentric model were correct?
- State Kepler’s three laws in your own words.
- Why did Kepler need Tycho Brahe’s data to formulate his laws?
- Which has more mass: an armful of feathers or an armful of lead? Which has more volume: a kilogram of feathers or a kilogram of lead? Which has higher density: a kilogram of feathers or a kilogram of lead?
- Explain how Kepler was able to find a relationship (his third law) between the orbital periods and distances of the planets that did not depend on the masses of the planets or the Sun.
-
Which major planet has the largest . . .
- semimajor axis?
- average orbital speed around the Sun?
- orbital period around the Sun?
- eccentricity?
- Why do we say that Neptune was the first planet to be discovered through the use of mathematics?
- Why was Brahe reluctant to provide Kepler with all his data at one time?
- According to Kepler’s second law, where in a planet’s orbit would it be moving fastest? Where would it be moving slowest?
- Write out Newton’s three laws of motion in terms of what happens with the momentum of objects.
- The gas pedal, the brakes, and the steering wheel all have the ability to accelerate a car—how?
- Explain how a rocket can propel itself using Newton’s third law.
- To calculate the momentum of an object, which properties of an object do you need to know?
- To calculate the angular momentum of an object, which properties of an object do you need to know?
- What was the great insight Newton had regarding Earth’s gravity that allowed him to develop the universal law of gravitation?
- Which of these properties of an object best quantifies its inertia: velocity, acceleration, volume, mass, or temperature?
- Pluto’s orbit is more eccentric than any of the major planets. What does that mean?
- Why is Tycho Brahe often called “the greatest naked-eye astronomer” of all time?
Thought Questions
- Draw a picture that explains why Venus goes through phases the way the Moon does, according to the heliocentric cosmology. Does Jupiter also go through phases as seen from Earth? Why?
- Show with a simple diagram how the lower parts of a ship disappear first as it sails away from you on a spherical Earth. Use the same diagram to show why lookouts on old sailing ships could see farther from the masthead than from the deck. Would there be any advantage to posting lookouts on the mast if Earth were flat? (Note that these nautical arguments for a spherical Earth were quite familiar to Columbus and other mariners of his time.)
- Parallaxes of stars were not observed by ancient astronomers. How can this fact be reconciled with the heliocentric hypothesis?
- Why do you think so many people still believe in astrology and spend money on it? What psychological needs does such a belief system satisfy?
- Consider three cosmological perspectives—the geocentric perspective, the heliocentric perspective, and the modern perspective—in which the Sun is a minor star on the outskirts of one galaxy among billions. Discuss some of the cultural and philosophical implications of each point of view.
- What were two arguments or lines of evidence in support of the geocentric model?
- Although the Copernican system was largely correct to place the Sun at the center of all planetary motion, the model still gave inaccurate predictions for planetary positions. Explain the flaw in the Copernican model that hindered its accuracy.
- During a retrograde loop of Mars, would you expect Mars to be brighter than usual in the sky, about average in brightness, or fainter than usual in the sky? Explain.
- The Great Pyramid of Giza was constructed nearly 5000 years ago. Within the pyramid, archaeologists discovered a shaft leading from the central chamber out of the pyramid, oriented for favorable viewing of the bright star Thuban at that time. Thinking about Earth’s precession, explain why Thuban might have been an important star to the ancient Egyptians.
- Hipparchus could have warned us that the dates associated with each of the natal astrology sun signs would eventually be wrong. Explain why.
- Explain three lines of evidence that argue against the validity of astrology.
- What did Galileo discover about the planet Jupiter that cast doubt on exclusive geocentrism?
- What did Galileo discover about Venus that cast doubt on geocentrism?
- Is it possible to escape the force of gravity by going into orbit around Earth? How does the force of gravity in the International Space Station (orbiting an average of 400 km above Earth’s surface) compare with that on the ground?
- What is the momentum of an object whose velocity is zero? How does Newton’s first law of motion include the case of an object at rest?
- Evil space aliens drop you and your fellow astronomy student 1 km apart out in space, very far from any star or planet. Discuss the effects of gravity on each of you.
- A body moves in a perfectly circular path at constant speed. Are there forces acting in such a system? How do you know?
- As friction with our atmosphere causes a satellite to spiral inward, closer to Earth, its orbital speed increases. Why?
- Two asteroids begin to gravitationally attract one another. If one asteroid has twice the mass of the other, which one experiences the greater force? Which one experiences the greater acceleration?
- How does the mass of an astronaut change when she travels from Earth to the Moon? How does her weight change?
- If there is gravity where the International Space Station (ISS) is located above Earth, why doesn’t the space station get pulled back down to Earth?
- If identical spacecraft were orbiting Mars and Earth at identical radii (distances), which spacecraft would be moving faster? Why?


1.7: Historical Changes in Retail
- Describe the overall change in the structure of the retail industry over the past 60 years
Prior to the 1800s retail was predominantly made up of local merchants who provided full service to customers, think of the classic “general store” in any old western movie. This full service often included offering credit, repairs, and offering one-on-one services to consumers to explain the features and benefits of products. Yet, breakthroughs in manufacturing during the industrial revolution lead to a marked increase in affordable quality items. In the early United States textile industry factories began to manufacture their-own ready-made clothes. Affordable blouses, frocks, pants and shirts flooded the market and these ready-made garments sold quickly. The quandary facing mill and factory owners was how best to market these items.
Two retail options existed at that time. The first, involved selling items directly to consumers through company-owned stores. The second option involved employing a commissioned agent in which a company agent would be responsible for delivering manufactured goods to shopkeepers who, in turn, would sell them. The question facing manufacturers and merchants was which option best suited their needs? Customers let it be known that they wanted ready access to a wide assortment of reasonable priced items, and that they were willing to pay a pretty penny for this service. Shoppers’ demands posed an interesting challenge to manufacturers and shopkeepers alike which lead to a new form of retailing: the department store.
Business historians often credit a Parisian retailer named Aristede Bouciaut (1810-1877) for developing the first department store. Called Le Bon Marche, this establishment featured the latest fashions and accessories within a spectacular setting. Early 19th century U.S. retailers from Boston to Richmond and from New York to Chicago quickly adopted Le Bon Marche layout and services and the modern department store was born. Large downtown department stores in major metropolitan city centers dominated retailing well into the post-war era.
In the 1950s, over 4,000 department stores operated nationwide with many new stores opening in suburban areas. Yet, by the mid-1960s, over half of the post-war department stores had closed their doors. This was especially noticeable in medium-sized U.S. cities many of which only had one or two downtown stores. The next three decades prompted further department store closings.
During the 1970’s many department stores closed and were replaced by discount department stores, shopping centers and large malls which soon accounted for 35% of the entire U.S. retail market. Discount department stores in particular, represented the fastest growing part of this phenomenon with annual profits exceeded $20,000,000,000. Customer loyalty soon became a relic of the past. Savvy new shoppers were more than willing to sacrifice the amenities of downtown department store for cheaper prices. Self-service stores with long check-out lines, indistinguishable departments and aisle upon aisle of items of picked-over garments became the norm, not the exception to the rule.
Fast forward to the 1990’s where the utilization of the Internet drastically impacted the retail industry and continues to drive product and marketing innovation to this day. The Internet has transformed how retailers and consumers view the intersections of product, place, price and time. Shoppers now have nearly unlimited access to an unprecedented assortment of products and their purchases are not restricted to a physical “brick-and-mortar” place or store hours. With a few clicks shoppers can compare prices of goods faster and more efficiently than before. Furthermore, retailers recognized that e-commerce allows for the optimization of inventories while selling a wide range of profit margin goods.
Online shopping allows consumers to directly buy goods or services from a seller over the Internet using a web browser. Consumers find a product of interest by visiting the website of the retailer directly or by searching among alternative vendors using a shopping search engine, which displays the same product’s availability and pricing at different e-retailers. As of 2016, customers can shop online using a range of different computers and devices, including desktop computers, laptops, tablet computers and smartphones.
An online shop evokes the physical analogy of buying products or services at a regular “bricks-and-mortar” retailer or shopping center; the process is called business-to-consumer (B2C) online shopping. When an online store is set up to enable businesses to buy from another businesses, the process is called business-to-business (B2B) online shopping. A typical online store enables the customer to browse the firm’s range of products and services, view photos or images of the products, along with information about the product specifications, features and prices.
The popularity and pervasiveness of online shopping shows no signs of slowing down which is putting traditional retailers in a unique position. How can brick-and-mortar stores integrate e-commerce strategically and successfully? In what ways will online retailers emulate brick-and-mortar stores as seen in the trend of popular online stores opening pop up shops for customers to shop in person. By having a better understanding of past industry trends and challenges, modern retailers can learn from their successful predecessors while also blazing a new trail forward.
Highly Recommended Additional Resource
Contributors and Attributions
- LET'S GO SHOPPING AT THE SQUARE. Authored by : Richard Klein, Ph.D. Located at : https://pressbooks.ulib.csuohio.edu/lets-go-shopping/front-matter/introduction-2/ . License : CC BY: Attribution
- Online Shopping. Provided by : Wikipedia. Located at : https://en.wikipedia.org/wiki/Online_shopping . License : CC BY-SA: Attribution-ShareAlike


1.S: Electronic Structure of Atoms (Summary)
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Understanding the electronic structure of atoms requires an understanding of the properties of waves and electromagnetic radiation. A basic knowledge of the electronic structure of atoms requires an understanding of the properties of waves and electromagnetic radiation. A wave is a periodic oscillation by which energy is transmitted through space. All waves are periodic, repeating regularly in both space and time. Waves are characterized by several interrelated properties.
- Electronic structure : arrangement of electrons in atoms
- Electromagnetic radiation : aka radiant energy ; form of energy that has wave characteristics and carries energy through space. All types of electromagnetic radiation move through a vacuum at a speed of 3.00 X 10 8 m/s (speed of light) .
- Wavelength : the distance between identical points on successive waves
- Frequency : the number of complete wavelengths that pass a given point in 1s
\[\nu λ = c \nonumber \]
where \(\nu\) = frequency, \(λ\)= wavelength, and \(c\) = speed of light
Wavelength is expressed in units of length.
- Electromagnetic spectrum : various types of electromagnetic radiations arranged in order of increasing wavelength.
Frequency is expressed in Hertz (Hz), also denoted by s -1 or /s
Quantum Effects and Photons
- Quantum : smallest quantity of energy that can be emitted or absorbed as electromagnetic radiation
\[E = hv \nonumber \]
where \(E\) = energy, \(h\) = Planck’s constant, \(\nu\) = frequency
Planck’s constant = 6.63 X 10 -34 J•s
According to Planck’s theory, energy is always emitted or absorbed in whole-number multiples of hv , for example, hv , 2hv , 3hv , and so forth. We say that the allowed energies are quantized (that is, their values are restricted to certain quantities).
6.2: Quantized Energy and Photons
Blackbody radiation is the radiation emitted by hot objects and could not be explained with classical physics. Max Planck postulated that energy was quantized and may be emitted or absorbed only in integral multiples of a small unit of energy, known as a quantum. The energy of a quantum is proportional to the frequency of the radiation; the proportionality constant h is a fundamental constant (Planck’s constant). Albert Einstein used the quantization of energy to explain the photoelectric effect
- The photoelectric effect: when photons of sufficiently high energy strike a metal surface, electrons are emitted from the metal. The emitted electrons are drawn toward the other electrode, which is a positive terminal. As a result, current flows in a circuit.
- Photon : smallest increment (a quantum ) of radiant energy; a photon of light with frequency v has an energy equal to hv .
- When a photon strikes the metal, its energy is transferred to an electron in the metal. A certain amount of energy is required for the electron to overcome the attractive forces that hold it within the metal. If the photons have less energy that this energy threshold, the electrons cannot escape from the metal surface. If a photon has sufficient energy, an electron is emitted. If the photon has more energy than necessary, the excess appears as kinetic energy of the emitted electron.
6.3: Line Spectra and the Bohr Model
There is an intimate connection between the atomic structure of an atom and its spectral characteristics. Most light is polychromatic and contains light of many wavelengths. Light that has only a single wavelength is monochromatic and is produced by devices called lasers, which use transitions between two atomic energy levels to produce light in a very narrow range of wavelengths. Atoms can also absorb light of certain energies, resulting in a transition from the ground state or a lower-energy e
Line Spectra
Radiation composed of a single wavelength is said to be monochromatic .
- Spectrum : distribution among various wavelengths of the radiant energy emitted or absorbed by an object
- Continuous spectrum : rainbow of colors, containing light of all wavelengths. Not all radiation sources produce a continuous spectrum
- Line spectrum : spectrum containing radiation of only specific wavelengths
Bohr’s Model
Electrons in a permitted orbit have a specific energy and are said to be in an "allowed" energy state. An electron in an allowed energy state will not radiate energy and therefore will not spiral into the nucleus.
\[E_n = -R_H \dfrac{1}{n^2} \nonumber \]
- R H = Rydberg constant: 2.18 X 10 -18 J
- n = principal quantum number, corresponds to the different allowed orbits for the electron
All energies given by this equation will be negative. The lower (more negative) the energy is, the more stable the atom is. The lowest energy state is that for which n=1.
- Ground state: lowest energy state of an atom, n=1
- Excited state: when the electron is in higher energy orbit (less negative), n=2 or higher
If n becomes infinitely large (∞), the electron is completely separated from the nucleus:
\[E_∞ = (-2.18 \times 10^{-18} J) \left(\dfrac{1}{∞^2}\right) = 0 \nonumber \]
Thus, the state in which the electron is removed from the nucleus is the reference, or zero-energy, state of the hydrogen atom. It is important to remember that this zero-energy state is higher in energy than the states with negative energies
Electrons can change from one energy state to another by absorbing or emitting radiant energy. Radiant energy must be absorbed for an electron to move to a higher energy state, but is emitted when the electron moves to a lower energy state. .
\[\Delta E = E_f – E_i \nonumber \]
- If n f > n i , then ∆E is positive, radiant energy is absorbed
- If n f < n i , then ∆E is negative, radiant energy is emitted
6.4: The Wave Behavior of Matter
An electron possesses both particle and wave properties. Louis de Broglie showed that the wavelength of a particle is equal to Planck’s constant divided by the mass times the velocity of the particle. The electron in Bohr’s circular orbits could thus be described as a standing wave, one that does not move through space. Werner Heisenberg’s uncertainty principle states that it is impossible to precisely describe both the location and the speed of particles that exhibit wavelike behavior.
- Momentum : the product of the mass, m , and the velocity, v , of a particle
- Matter waves : term used to describe the wave characteristics of a particle
\[λ = h / mv \nonumber \]
λ = wavelength, h = Planck’s constant, m = mass, v = velocity
The Uncertainty Principle
- Uncertainty principle : theory first put forth by Heisenberg, states that is it impossible to determine both the exact momentum of the electron and its exact location.
6.5: Quantum Mechanics and Atomic Orbitals
There is a relationship between the motions of electrons in atoms and molecules and their energies that is described by quantum mechanics. Because of wave–particle duality, scientists must deal with the probability of an electron being at a particular point in space. To do so required the development of quantum mechanics, which uses wavefunctions to describe the mathematical relationship between the motion of electrons in atoms and molecules and their energies.
- Wave functions : represented by ψ , square of wave function, ψ 2 , provides information about an electron’s location when it is in an allowed energy state.
- Probability density : represented by ψ 2 , value that represents the probability that an electron will be found at a given point in space
- Electron density : the probability of finding and electron at any particular point in an atom. Equals ψ 2 .
Orbitals and Quantum Numbers
- Orbital : allowed energy state of an electron in the quantum-mechanical model of the atom; also used to describe the spatial distribution of an electron. Defined by the value of 3 quantum numbers; n, l, and m l .
| Value of l | 0 | 1 | 2 | 3 |
|---|---|---|---|---|
| Letter used | s | p | d | f |
- The principal quantum number, n , can have integral values of 1, 2, 3 and so forth. As n increases, the orbital becomes larger; the electron has a higher energy and is farther away from the nucleus.
- The second quantum number, l , can have integral values from 0 to n – 1 for each value of n . This quantum number defines the shape of the orbital. Generally designated by the letters s , p , d , and f . These correspond to values ranging from 0 to 3.
- The magnetic quantum number, m l , can have integral values between l and –l , including zero. This quantum number describes the orientation of the orbital in space.
Electron shell : collection of orbitals with the same value of n
Subshell : one or more orbitals with the same set of n and l values
- Each shell is divided into the number of subshells equal to the principal quantum number, n , for that shell. The first shell consists of only the 1s subshell; the second shell consists of two subshells, 2s and 2p; the third of three subshell, 3s, 3p and 3d, and so forth.
- Each subshell is divided into orbitals. Each s subshell consists of one orbital; each p subshell of three orbitals, each d subshell of five, and each f subshell of seven orbitals.
6.6: 3D Representation of Orbitals
Orbitals with l = 0 are s orbitals and are spherically symmetrical, with the greatest probability of finding the electron occurring at the nucleus. Orbitals with values of n > 1 and l = 0 contain one or more nodes. Orbitals with l = 1 are p orbitals and contain a nodal plane that includes the nucleus, giving rise to a dumbbell shape. Orbitals with l = 2 are d orbitals and have more complex shapes with at least two nodal surfaces. l = 3 orbitals are f orbitals, which are still more complex.
The s Orbitals: 1s orbital: most stable, spherically symmetric, figure indicates that the probability decreases as we move away from the nucleus.
- Nodal surfaces (nodes) : intermediate regions where ψ 2 goes to zero. The number of nodes increases with increasing value for the principal quantum number, n .
The p Orbitals: Electron density is concentrated on two sides of the nucleus, separated by a node at the nucleus. The orbitals of a given subshell have the same size and shape but differ from each other in orientation. The axis along which the orbital is oriented is not related to m l .
6.7: Many-Electron Atoms
In addition to the three quantum numbers (n, l, ml) dictated by quantum mechanics, a fourth quantum number is required to explain certain properties of atoms. This is the electron spin quantum number (ms), which can have values of +½ or −½ for any electron, corresponding to the two possible orientations of an electron in a magnetic field. This is important for chemistry because the Pauli exclusion principle implies that no orbital can contain more than two electrons (with opposite spin).
Although the shapes of the orbitals for many-electron atoms are the same as those for hydrogen, the presence of more than one electron greatly changes the energies of the orbitals. In hydrogen, the energy of an orbital depends only on its principal quantum number, however, in many-electron atoms, electron-electron repulsions cause different subshells to be at different energies
Effective Nuclear Charge
- Effective nuclear charge : net positive charge attracting electrons
\[Z_{eff} = Z – S \nonumber \]
- Z eff = effective nuclear charge
- Z = number of protons in the nucleus
- S = average number of electrons between the nucleus and electron in question
- Screening effect : effect of inner electrons in decreasing the nuclear charge experienced by outer electrons
Energies of Orbitals
The extent to which an electron will be screened by the other electrons depends on its electron distribution as we move outward from the nucleus.
- In a many-electron atom, for a given value of n, Z eff decreases with increasing value of l.
- In a many-electron atom, for a given value of n, the energy of an orbital increases with increasing value of l.
Degenerate : orbitals that have the same energy
Electron Spin and the Pauli Exclusion Principle
- Electron spin : property of the electron that makes it behave as though it were a tiny magnet. The electron behaves as if it were spinning on its axis; electron spin is quantized.
- Electron spin quantum number : denoted as m s . It can only have two possible values, +½ and –½, which we can interpret as indicating the two opposite directions in which the electron can spin.
- Pauli exclusion principle : states that no two electrons in an atom can have the same set of four quantum numbers n , l , m l , m s . This means that if we wish to put two electrons in an orbital and satisfy Pauli’s exclusion principle, our only choice is to assign different m s values to the electrons. Because there are only two values, we can conclude that an electron can hold a maximum of two electrons and they must have opposite spins .
6.8: Electron Configurations
Based on the Pauli principle and a knowledge of orbital energies obtained using hydrogen-like orbitals, it is possible to construct the periodic table by filling up the available orbitals beginning with the lowest-energy orbitals (the aufbau principle), which gives rise to a particular arrangement of electrons for each element (its electron configuration). Hund’s rule says that the lowest-energy arrangement of electrons is the one that places them in degenerate orbitals with parallel spins.
- Electron configuration : the way in which the electrons are distributed among the various orbitals. The most stable, or ground, electron configuration of an atom is that in which the electrons are in the lowest possible energy level
- Orbital diagram : representation of electron configuration in which each orbital is represented by a box and each electron by a half-arrow. A half-arrow pointing upward represents an electron with positive spin; one pointing downward represents an electron with a negative spin.
Writing Electron Configurations
- Hund’s rule : rule stating that electrons occupy degenerate orbitals in such a way as to maximize the number of electrons with the same spin. In other words, each orbital has one electron placed in it before paring of electron in orbitals occurs. Note that this rule applies to orbitals that are degenerate , which means that they have the same energy.
- Valence electrons : electrons in the outer shells
- Core electrons : electrons in the inner shells
- Transition elements : aka Transition metals ; elements of the d orbitals
- Lanthanide elements : aka Rare-earth elements ; 14 elements of the 4f orbitals, # 58-71
- Actinide elements : 14 elements of 5f orbitals, # 90-103. Most are not found in nature.
6.9: Electron Configurations and the Periodic Table
The arrangement of atoms in the periodic table results in blocks corresponding to filling of the ns, np, nd, and nf orbitals to produce the distinctive chemical properties of the elements in the s block, p block, d block, and f block, respectively.
- Main group elements : aka Representatives ; s and p block elements
- F-block metals : 28 elements located below the table, f block elements


Ethics and Corruption
To begin our discussion of corruption, let’s first define it in a business context. Corruption is “giving or obtaining advantage through means which are illegitimate, immoral, and/or inconsistent with one’s duty or the rights of others. Corruption often results from patronage.
Our modern understanding of business ethics notes that following culturally accepted norms is not always the ethical choice. What may be acceptable at certain points in history, such as racism or sexism, became unacceptable with the further development of society’s mind-set. What happens when cultures change but business practices don’t? Does that behavior become unethical, and is the person engaged in the behavior unethical? In some cultures, there may be conflicts with global business practices, such as in the area of gift giving, which has evolved into bribery—a form of corruption.
Paying bribes is relatively common in many countries, and bribes often take the form of
grease payments
, which are small inducements intended to expedite decisions and transactions. In India and Mexico, for example, a grease payment may help get your phones installed faster—at home or at work. Transparency International tracks illicit behavior, such as bribery and embezzlement, in the public sector in 180 countries by surveying international business executives. It assigns a CPI (Corruption Perceptions Index) rating to each country. New Zealand, Denmark, Singapore, and Sweden have the lowest levels of corruption, while the highest levels of corruption are seen in most African nations, Russia, Myanmar, and Afghanistan.
Even the most respected of global companies has found itself on the wrong side of the ethics issue and the law. In 2008, after years of investigation, Siemens agreed to pay more than 1.34 billion euros in fines to American and European authorities to settle charges that it routinely used bribes and slush funds to secure huge public-works contracts around the world. “Officials said that Siemens, beginning in the mid-1990s, used bribes and kickbacks to foreign officials to secure government contracts for projects like a national identity card project in Argentina, mass transit work in Venezuela, a nationwide cell phone network in Bangladesh and a United Nations oil-for-food program in Iraq under Saddam Hussein. ‘Their actions were not an anomaly,’ said Joseph Persichini Jr., the head of the Washington office of the Federal Bureau of Investigation. ‘They were standard operating procedures for corporate executives who viewed bribery as a business strategy.’”
Ethics in Action
Each year Transparency International analyzes trends in global corruption. The following is an excerpt from their 2010 Global Corruption Barometer report.
“Corruption has increased over the last three years, say six out of 10 people around the world. One in four people report paying bribes in the last year. These are the findings of the 2010 Global Corruption Barometer.
The 2010 Barometer captures the experiences and views of more than 91,500 people in 86 countries and territories, making it the only world-wide public opinion survey on corruption.
Views on corruption were most negative in Western Europe and North America, where 73 per cent and 67 per cent of people respectively thought corruption had increased over the last three years.
“The fall-out of the financial crises continues to affect people’s opinions of corruption, particular in North America and Western Europe. Institutions everywhere must be resolute in their efforts to restore good governance and trust,” said Huguette Labelle, Chair of Transparency International.
In the past 12 months one in four people reported paying a bribe to one of nine institutions and services, from health to education to tax authorities. The police are cited as being the most frequent recipient of bribes, according to those surveyed. About 30 per cent of those who had contact with the police reported having paid a bribe.
More than 20 countries have reported significant increases in petty bribery since 2006. The biggest increases were in Chile, Colombia, Kenya, FYR Macedonia, Nigeria, Poland, Russia, Senegal and Thailand. More than one in two people in Sub-Saharan Africa reported paying a bribe—more than anywhere else in the world.
Poorer people are twice as likely to pay bribes for basic services, such as education, than wealthier people. A third of all people under the age of 30 reported paying a bribe in the past 12 months, compared to less than one in five people aged 51 years and over.
Most worrying is the fact that bribes to the police have almost doubled since 2006, and more people report paying bribes to the judiciary and for registry and permit services than five years ago.
Sadly, few people trust their governments or politicians. Eight out of 10 say political parties are corrupt or extremely corrupt, while half the people questioned say their government’s action to stop corruption is ineffective.
“The message from the 2010 Barometer is that corruption is insidious. It makes people lose faith. The good news is that people are ready to act,” said Labelle. “Public engagement in the fight against corruption will force those in authority to act—and will give people further courage to speak out and stand up for a cleaner, more transparent world.”
Source: Transparency International, “Global Corruption Barometer 2010,” accessed February 22, 2011,
http://www.transparency.org/policy_research/surveys_indices/gcb/2010
.
Gift giving in the global business world is used to establish or pay respects to a relationship. Bribery, on the other hand, is more commonly considered the practice in which an individual would benefit with little or no benefit to the company. It’s usually paid in relation to winning a business deal, whereas gift giving is more likely to be ingrained in the culture and not associated with winning a specific piece of business. Bribery, usually in the form of a cash payment, has reached such high proportions in some countries that even locals express disgust with the corruption and its impact on daily life for businesses and consumers.
The practice of using connections to advance business interests exists in just about every country in the world. However, the extent and manner in which it is institutionalized differs from culture to culture.
In Western countries, connections are viewed informally and sometimes even with a negative connotation. In the United States and other similar countries, professionals prefer to imply that they have achieved success on their own merits and without any connections. Gift giving is not routine in the United States except during the winter holidays, and even then gift giving involves a modest expression. Businesses operating in the United States send modest gifts or cards to their customers to thank them for business loyalty in the previous year. Certain industries, such as finance, even set clear legal guidelines restricting the value of gifts, typically a maximum of $100.
In contrast, Asian, Latin American, and Middle Eastern cultures are quick to value connections and relationships and view them quite positively. Connections are considered essential for success. In Asia, gift giving is so ingrained in the culture, particularly in Japan and China, that it is formalized and structured.
For example, gift giving in Japan was for centuries an established practice in society and is still taken seriously. There are specific guidelines for gift giving depending on the identity of the giver or recipient, the length of the business relationship, and the number of gifts exchanged. The Japanese may give gifts out of a sense of obligation and duty as well as to convey feelings such as gratitude and regret. Therefore, much care is given to the appropriateness of the gift as well as to its aesthetic beauty. Gift giving has always been widespread in Japan.
Today there are still business gift-giving occasions in Japan, specifically
oseibo
(year’s end) and
ochugen
(midsummer). These are must-give occasions for Japanese businesses. Oseibo gifts are presented in the first half of December as a token of gratitude for earlier favors and loyalty. This is a good opportunity to thank clients for their business.
Ochugen
usually occurs in mid-July in Tokyo and mid-August in some other regions. Originally an occasion to provide consolation to the families of those who had died in the first half of the year, ochugen falls two weeks before
obon
, a holiday honoring the dead.
Businesses operating in Japan at these times routinely exchange oseibo and ochugen gifts. While a professional is not obligated to participate, it clearly earns goodwill. At the most senior levels, it is not uncommon for people to exchange gifts worth $300 or $400. There is an established price level that one should pay for each corporate level.
Despite these guidelines, gift giving in Japan has occasionally crossed over into bribery. This level of corruption became more apparent in the 1980s as transparency in global business gained media attention. Asians tend to take a very different view of accountability than most Westerners. In the 1980s and 1990s, several Japanese CEOs resigned in order to apologize and take responsibility for their companies’ practices, even when they did not personally engage in the offending practices. This has become an accepted managerial practice in an effort to preserve the honor of the company. While Japanese CEOs may not step down as quickly as in the past, the notion of honor remains an important business characteristic.
Long an established form of relationship development in all business conducted in Asia, the Arab world, and Africa, gift giving was clearly tipping into outright bribery. In the past two decades, many countries have placed limits on the types and value of gifts while simultaneously banning bribery in any form. In the United States, companies must adhere to the Foreign Corrupt Practices Act, a federal law that specifically bans any form of bribery. Even foreign companies that are either listed on an American stock exchange or conduct business with the US government come under the purview of this law.
There are still global firms that engage in questionable business gift giving; when caught, they face fines and sanctions. But for the most part, firms continue with business as usual. Changing the cultural practices of gift giving is an evolving process that will take time, government attention, and more transparency in the awarding of global business contracts.
Companies and their employees routinely try to balance ethical behavior with business interests. While corruption is now widely viewed as unethical, firms still lose business to companies that may be less diligent in adhering to this principle. While the media covers stories of firms that have breached this ethical conduct, the misconduct of many more companies goes undetected. Businesses, business schools, and governments are increasingly making efforts to deter firms and professionals from making and taking bribes. There are still countless less visible gestures that some would argue are also unethical. For example, imagine that an employee works at a firm that wants to land a contract in China. A key government official in China finds out that you went to the business school that his daughter really wants to attend. He asks you to help her in the admission process. Do you? Should you? Is this just a nice thing to do, or is it a potential conflict of interest if you think the official will view your company more favorably? This is a gray area of global business ethics. Interestingly, a professional’s answer to this situation may depend on his or her culture. Cultures that have clear guidelines for right and wrong behavior may see this situation differently than a culture in which doing favors is part of the normal practice. A company may declare this inappropriate behavior, but employees may still do what they think is best for their jobs. Cultures that have a higher tolerance for ambiguity, as this chapter discusses, may find it easier to navigate the gray areas of ethics—when it is not so clear.
Most people agree that bribery in any form only increases the cost of doing business—a cost that is either absorbed by the company or eventually passed on to the buyer or consumer in some form. While businesses agree that corruption is costly and undesirable, losing profitable business opportunities to firms that are less ethically motivated can be just as devastating to the bottom line. Until governments in every country consistently monitor and enforce anticorruption laws, bribery will remain a real and very challenging issue for global businesses.


16: Appendices Last updated Save as PDF Page ID 44198 OpenStax OpenStax 16.1: How to Study for an Introductory Astronomy Class (Appendix A) 16.2: Astronomy Websites, Images, and Apps (Appendix B) 16.3: Scientific Notation (Appendix C) 16.4: Units Used in Science (Appendix D) 16.5: Some Useful Constants for Astronomy (Appendix E) 16.6: Physical and Orbital Data for the Planets (Appendix F) 16.7: Selected Moons of the Planets (Appendix G) 16.8: Future Total Eclipses (Appendix H) 16.9: The Nearest Stars, Brown Dwarfs, and White Dwarfs (Appendix I) 16.10: The Brightest Twenty Stars (Appendix J) 16.11: The Chemical Elements (Appendix K) 16.12: The Constellations (Appendix L) 16.13: Star Chart and Sky Event Resources Index (Appendix M)


6.1: Introduction to Integrals
Suppose construction workers needed to remove dirt in a hill in order to run a road though it. The swath needed to be excavated is \(10\) meters wide, and the hill is parabola shaped. Here is a picture:
How much dirt needs to be removed? What do we need to know to solve the problem?
That’s right — we need to know the volume of the region we’re excavating. Here is a picture of the region we are removing:
Such an object is called a “prism” — it’s basically two dimensional shape that has been given a little thickness. Finding the volume involves finding the area of the shape times its thickness:
In this case, the area is labeled \(A\) in the diagram, and the width is \(10\). So the amount of dirt being hauled away is \(10A\). But what is ? How do we find it? That is where integration comes in.
\(A\) is a parabola like shape, but let’s say it is bounded on top by the function . Thus you get a picture like this:
How do we find the area of a curved shape like this? Well, we don’t know how to find the area of an arbitrary curved shape. But we DO know how to find the area of a rectangle: it is height times width. So let’s use rectangles:
So it’s not a great approximation yet, but bear with me. The area of the boxes does approximate the area under the curve to some extent. But how do we figure out the area of the rectangles? Well, that’s height times width, and we can see that the width of each box is \(10\). So we just need the height of each rectangle.
When I drew each rectangle, I made it so that the right side of the rectangle was exactly the height of the function. The height of the function is something we can find! That’s because we know the hill follows the function \(x = 10\) into our function. So the height is . The height of the second rectangle is . The third rectangle has height , the fourth rectangle has height , and the fifth has height .
If we take these heights and multiply by the width, we get the area of each rectangle.
Adding up all the area from all the rectangles, we have \(32 + 48 + 48 + 32 + 0 = 160\) m\(^2\). This is an approximation of the area.
Now you might say that this approximation might not be very good, and you’re correct. It certainly gives the rough idea, which might be all that we need. But if we need a very precise answer, \(160\) isn’t good enough. So what can we do? Let’s use more rectangles!
The idea of using rectangles like this to get better and better approximations of area is called a Riemann Sum. Now, we could find the height and width of each of those rectangles, but it would be a bit tedious. Since mathematicians are lazy, we often have a computer do the work for us. For example, website “MathWorld” has a Riemann Sum calculator: http://mathworld.wolfram.com/RiemannSum.html . Using this calculator, we can see that when using \(20\) rectangles, the sum becomes \(166.25\). This is called numeric integration (If you use more and more rectangles, you can actually find a very precise answer of \(166.667\) — this is how the program computes the “actual area”. However, this is still an approximation, not an exact value.)
What does this have to do with the dirt problem? Remember, we were trying to find the volume of this slice:
What we have done with the Riemann sums is find \(A = 166.667\). To find how much dirt is hauled away, we just need to multiply by the width of the prism, which is \(10\) m. Hence \(1666.67\) cubic meters of dirt must be hauled away.


1.1: Components of an Information System
The Components of Information Systems
As we have learned in the previous section, Information systems deal with the overall combination of different parts that work together such as hardware, software, telecommunications technologies, and people to process data for, typically, organization needs or settings. Learning and having been taught that Information Systems deal with current technologies and software programs is one minor aspect of a bigger picture. Information systems deal with four major components: Technology, People, Data, and Process.
Technology
Technology can be thought of as the application of scientific knowledge for practical purposes. From the invention of the wheel to the harnessing of electricity for artificial lighting, technology is a part of our lives in so many ways that we tend to take it for granted. The development of Hardware & Software created brand new opportunities for organizations and clients to perform day-to-day tasks with ease.
Hardware
Hardware is the part of an information system you can touch – the physical components of the technology. Computers, keyboards, disk drives, iPads, and flash drives are all examples of information systems hardware. As a Project Manager or Systems Analyst, you will not be responsible for developing the hardware of systems or designing a brand new computer, but you will be expected to be familiar with computer hardware components and how they work. Computer Engineers will be responsible for developing these systems for the vendors from which you will choose to buy their systems.
Figure 1: Computer with keyboard, Figure 2: Motherboard with other components.
mouse, screen & chassis.
Software
Software is a set of instructions that tells the hardware what to do. Software is not tangible – it cannot be touched. Programmers create software that sends series of instructions for the computerfollow. There are several categories of software, with the two main categories being operating-system software, which makes the hardware usable, and application software, which does something useful. Examples of operating systems include Microsoft Windows on a personal computer and Google’s Android on a mobile phone. Examples of application software are Microsoft Excel and Angry Birds. Software will be explored more thoroughly in chapter 3.
Figure 3: Windows 8 OS Software Figure 3: Audio Mixing application software
with preinstalled application software
Hardware and Software have come a really long way throughout time, thanks to the innovator and inventors of these two components. Communication and data transmission has been made possible. Computer networking, Networking, Or network communication is the concept of being able to connect with other individuals or organizations to share and communicate data over computer systems called a Computer network. Information systems in the present heavily rely on being able to communicate with other systems through this means. The concept of the internet was not always around, so computer systems were not always able to communicate with others in remote locations like we see today. Computer networking will be covered in greater detail in chapter 3.
The development of
Cloud Computing
is another benefit that has emerged. Cloud computing is the use of IT resources of a vendor or company through the internet (also called “the cloud”) usually through a subscription-based model. These IT resources are not locally stored on the client’s premises and provide copious amounts of advantages as well as disadvantages. Cloud computing will be discussed in greater detail in chapter 3 as well
.
Data
The second component is data. You can think of data as a collection of facts. For example, your street address, the city you live in, and your phone number are all pieces of data. Like software, data is also intangible. By themselves, pieces of data are not really very useful. But aggregated, indexed, and organized together into a database, data can become a powerful tool for businesses. In fact, all of the definitions presented at the beginning of this chapter focused on how information systems manage data. Organizations collect all kinds of data and use it to make decisions. These decisions can then be analyzed as to their effectiveness and the organization can be improved. Chapter 4 will focus on data and databases, and their uses in organizations.
People
Where does the information come from? Is it from science? Or from computers? By no means! It comes from us! People!
People have been the conveyors of creating information out of raw data. It is out of the data that people collect that we are able to get information that is used to develop useful tools and products that are used daily. It is people that create buildings, agricultural products, and so much more. From this, you can understand the crucial roles that people in your organization and in other parts affect the way you will manage or develop an information system
When thinking about information systems, it is easy to get focused on the technology components and forget that we must look beyond these tools to fully understand how they integrate into an organization. A focus on the people involved in information systems is the next step. From the front-line help-desk workers to systems analysts, to programmers, all the way up to the chief information officer (CIO), the people involved with information systems are an essential element that must not be overlooked.
Process
The last component of information systems is process . A process is a series of steps undertaken to achieve a desired outcome or goal. Information systems are becoming more and more integrated with organizational processes, bringing more productivity and better control to those processes. But simply automating activities using technology is not enough – businesses looking to effectively utilize information systems do more. Using technology to manage and improve processes, both within a company and externally with suppliers and customers is the ultimate goal. Technology buzzwords such as “business process reengineering,” “business process management,” and “enterprise resource planning” all have to do with the continued improvement of these business procedures and the integration of technology with them. Businesses hoping to gain an advantage over their competitors are highly focused on this component of information systems. We will discuss processes in greater detail in the second part of this chapter.
References
Bourgeois, D., & Bourgeois, D. T. (2014, February 28). Chapter 2: Hardware. Retrieved from https://bus206.pressbooks.com/chapte...tems-hardware/
Management Information Systems (Business 206). (n.d.). Retrieved from https://www.oercommons.org/courses/m...n-systems/view
Management Information Systems (Business 206). (n.d.). Retrieved from https://www.oercommons.org/courses/m...n-systems/view