______________________________________________________________________________ 3. Use a colon between independent clauses if the second clause summarizes or explains the first. A colon is used to introduce an idea that is an explanation or continuation of the one that comes before the colon. The colon can be considered as a gateway inviting the reader to go on. Look at these examples: Ben suddenly canceled his evening plans for a simple reason: his car was out of gas.
Measures of Center: Mean, Median, and Mode Measures of center generally tell us about the middle, or center, of a distribution. They are the mean, the median, and the mode. Each plays a useful role in Statistics. The Mean The mean, or arithmetic average, is calculated by adding all the data values and dividing by the number of values.
Median and Quartiles The median is a measure of center (location) of a list of numbers. It is the number such that at least half the data is less than or equal to it and at least half is greater than or equal to it. Note that, unlike the mean, the median is not inï¬uenced by a few large values in the list. A measure of dispersion that accompanies the median is the interquartile range (IQR). It is the distance between the upper and lower quartiles. To ï¬nd the quartiles and median, put the numbers in order from smallest to largest. Then if there are an odd number of numbers in the list the median can be found by counting in from either end of the list to the (n + 1)/2nd number. This will be the median. If there