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Difference Between Reliability and Validity

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❶Reliability refers to the repeatability of findings. This means that such experiments are more difficult to repeat and are inherently less reliable.

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What is Reliability?
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If so, the test can then be described as reliable. To be reliable, an inventory measuring self-esteem should give the same result if given twice to the same person within a short period of time.

IQ tests should not give different results over time as intelligence is assumed to be a stable characteristic. Validity refers to the credibility or believability of the research. Are the findings genuine? Is hand strength a valid measure of intelligence? Almost certainly the answer is "No, it is not.

The answer depends on the amount of research support for such a relationship. Internal validity - the instruments or procedures used in the research measured what they were supposed to measure. As part of a stress experiment, people are shown photos of war atrocities. After the study, they are asked how the pictures made them feel, and they respond that the pictures were very upsetting. In this study, the photos have good internal validity as stress producers.

The conclusion validity is focused more on the relationship between the outcome and the program. Internal validity is more on asking what kind of relationship is there between the outcome and the program. Construct validity analyzes how strong the outcome is. External validity is focused more on the general concept of the outcome.

These are some of the differences between reliability and validity. Reliability is more on the consistency of a measurement, while validity is focused more on how strong the outcome of the program was.

Reliability is easier to determine, because validity has more analysis just to know how valid a thing is. Reliability is determined by tests and internal consistency, while validity has four types, which are the conclusion, internal validity, construct validity, and external validity. There is no need to resubmit your comment. Notify me of followup comments via e-mail. User assumes all risk of use, damage, or injury. You agree that we have no liability for any damages.

Second, we can ask the student's classroom teacher to give us a rating of the student's ability based on their own classroom observation. The first cell on the upper left shows the comparison of the verbal written test score with the verbal written test score. But how can we compare the same measure with itself?

We could do this by estimating the reliability of the written test through a test-retest correlation, parallel forms, or an internal consistency measure See Types of Reliability.

What we are estimating in this cell is the reliability of the measure. The cell on the lower left shows a comparison of the verbal written measure with the verbal teacher observation rating.

Because we are trying to measure the same concept, we are looking at convergent validity See Measurement Validity Types. The cell on the upper right shows the comparison of the verbal written exam with the math written exam.

Here, we are comparing two different concepts verbal versus math and so we would expect the relationship to be lower tha n a comparison of the same concept with itself e. Thus, we are trying to discriminate between two concepts and we would consider this discriminant validity. Finally, we have the cell on the lower right. Here, we are comparing the verbal written exam with the math teacher observation rating. Like the cell on the upper right, we are also trying to compare two different concepts verbal versus math and so this is a discriminant validity estimate.

But here, we are also trying to compare two different methods of measurement written exam versus teacher observation rating.

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Education Research and Perspectives, Vol, No.1 Validity and Reliability in Social Science Research Ellen A. Drost California State University, Los Angeles.

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When we look at reliability and validity in this way, we see that, rather than being distinct, they actually form a continuum. On one end is the situation where the concepts and methods of measurement are the same (reliability) and on the other is the situation where concepts and methods of measurement are different (very discriminant validity).

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Issues of research reliability and validity need to be addressed in methodology chapter in a concise manner. Reliability refers to the extent to which the same answers can be obtained using the same instruments more than one time. In simple terms, if your research is associated with high levels of. Reliability and validity seem to be synonymous, but they do not mean the same thing. They are actually different things, different terms when they are explained in a technical manner. These terms are often used on scholastic outputs such as thesis studies, term papers, research papers, and the likes.