PSYC 2002 Lecture 8: Statistics
12 Feb 2019
School
Department
Course
Professor
Document Summary
The shape of a z-score distribution is the same as the shape of the underlying distribution of raw scores. Each x score is simply re-labelled as z-score. Characteristics of z-score distribution: mean and standard deviation. The mean of a z-score distribution is always zero. The standard deviation of z-score distribution is always one. Scores that have been transformed into z-scores can be compared on a standard basis. E. g. , two tests psychology and math; you get a grade of 79% on the psychology and a grade of 80% on the math test. If mean and sd of the psychology test are 70% and 5%, respectively, while the mean and sd of the math test are 68% and 10%, you can transform the scores into standardized scores for purposes of comparison. Z-score for psych test is (79-70)/5 = 9/5 = 1. 8. Z-score for math is (80-68)/10 = 12/10 = 1. 2.
