Any phenomenon we decide to “measure” in psychology, whether it is a physical or mental characteristic, will inevitably contain some error. For example, you can step on the same scale three consecutive times to weigh yourself and get three slightly different readings. To deal with this, you might take the average of the three weight measures as the best guess of your current weight. In most field settings, however, we do not have the luxury of administering our measurement instrument multiple times. We get one shot at it and we had better obtain the most accurate estimate possible with that one administration. Therefore, if we have at least some measurement error estimating a physical ...
Classical True Score Theory and Reliability
Classical true score theory and reliability