PSYC 2530 Chapter Notes - Chapter 4: Xg Technology, Standard Deviation, Variance
Document Summary
Diversity = differences from person to person. Consistency = differences in scores for the same person. Variability provides a quantitative measure of the differences between scores in a distribution and describes the degree to which the scores are spread out or clustered together: serves two purposes: Describes the distribution in terms of distance between scores. Measures how well an individual score represents the entire distribution. Deviation is distance from the mean: deviation score = x - . Two parts, sign (+ or -) and the number. Population variance equals the mean squared deviation. Variance is the average squared distance from the mean: standard deviation is the square root of the variance and provides a measure of the standard, or average, distance from the mean. The mean, standard deviation, and variance should be used only with numerical scores from interval or ratio scales of measurement.