PSYC 3430 Lecture Notes - Lecture 3: Kurt Lewin, Takers, Psychological Testing
Document Summary
Anything that exists, exists in some quantity and can therefore be measured. Any measure, to be scientifically useful, must have reliability and validity. It is the degree to which test scores for a an individual test taker or group of test takers are consistent over repeated applications. No psychological test is completely consistent, however, a measurement that is unreliable is worthless. A student receives a score of 100 on one intelligence tests and. 114 in another or imagine that every time you stepped on a scale it showed a different weight. The consistency of test scores is critically important in determining whether a test can provide good measurement. Internal consistency: measures the reliability of a test solely on the number of items on the test and the intercorrelation among the items. Therefore, it compares each item to every other item.