validity and reliability are testing terms used about

This would include things like the ordering of survey questions, the time of day Joey took the survey, and the time he gets to think about each question before responding. The more they change from one month to the next, the lower we predict the survey’s overall reliability to be.Īll study criteria must remain consistent through all three months. Reliability is equally as important in the world of social sciences as it is in the physical sciences. For instance, if Joey completes a survey once during January, February, and again in March, we could call the survey ‘reliable’ if his scores do not waver. But when you get into situations where high reliability is essential – like computing the theoretical atomic weight of a kilogram – then you start to see where seemingly small deviations can wreak havoc on the overall accuracy of your results. If you were a general contractor framing a new house or installing kitchen cabinets, the level of measurement reliability described above (+/- 1/16th”) is probably fine. As a result, your reliability (i.e., consistency) is good – maybe even great – but not perfect. Is the distance closer to 5-11/16th inches, or 5-3/4th? Did you start measuring from the inside or outside of the line last time? In this situation, you impose a qualitative interpretation of a tool believed to afford a quantitative result. One reason for this is that your measurement reliability is dependent on your interpretation of what the tool is saying.

However, the truth is that each measurement you made wouldn’t be exactly the same as the ones before it. If you were to perform the measurement several times in a row, your results would have relatively high reliability. For example, if you wanted to know the distance between points on a flat surface, you could use a ruler. In domains such as mechanical engineering, reliability is pretty easy to conceptualize. Reliability is the degree to which a specific research method or tool is capable of producing consistent results from one test to the next. To start things off, let’s get on the same page about what we mean by the term, “reliability”.

Criterion-Related Validity (Concurrent & Predictive).

If you have an example you’d like to share, please talk about it in the comment section below! Jump to: The tricky stuff comes when we examine the different types of validity and reliability, as well as when or why they matter the most.īelow we’ve outlined the basics of validity and reliability as it applies to user-centered research. It’s not necessarily the difference between them that is so baffling it’s more the fact that there is so much more to it. In research, no two concepts are more confused with one another than validity and reliability.

Validity and reliability are testing terms used about