PSYCH 100A Lecture Notes - Lecture 5: Standard Deviation
Document Summary
Problem: no frame of reference, have to obtain information the distribution in order for scores to be meaningful, need to compute mean and standard deviation of ddistriution in order to interpret the score. Solution: transform the raw score into a z-score (standard scores) that identify and describe the exact location every score in a distribution. Purpose: each z-score tells the exact location of the original x value within the distribution, the z-scores from a standardized distribution can be directly compared to other distributions that also have been transformed into z-scores. Properties of the z distribution: shape: same shape as original distribution, mean: z-score distribution always has mean of 0, std deviation: z-score distribution always has std dev of 1. Z-score for x = 95? z-score to raw score (x) In a population with , a score of x = 59 corresponds to z = -2. 00.
