PSYC 3250 Lecture Notes - Lecture 8: Square Root, Rune Rk, Tx1

• School: University of Guelph
• Department: Psychology
• Course: PSYC 3250
• Professor: graceewes

Document Summary

One of the most influential theories in measurement. Ex) tim completes a math test out of 100. He knows the correct answer to 80 questions. Lack of sleep, broken pencil, dismissed or looks over a question/careless errors. We observe x, which is made up of t and e. Where the entire testing population is affected in the same way. T (true score) and e (error) are theoretical constructs (we don"t observe them) Random measurement error is a result of chance factors. General principles of classical test theory: mean of error scores in a population=0, r between true scores and error scores=0, r between error scores on different measurements=0. Error: the difference between sample items chosen for the test and all possible items. Typically considered the largest source of error in test scores. Random changes in the testing environment and the test taker associated with the time of testing, which impact an individual"s score.