Statistics for the Behavioral Sciences, 4/e

Michael Thorne, Mississippi State University -- Mississippi State
Martin Giesen, Mississippi State University -- Mississippi State

Measures of Dispersion and Standard Scores

Definitions

dispersion	spread of the scores around the mean



range	difference between the highest and lowest scores in a distribution



average deviation	average amount that each score in a distribution deviates from the distribution's mean



absolute value of a score	value of the score without regard to its sign



variance	average of the squared deviations of scores from the mean



standard deviation	square root of the variance



sum of squares	sum of the squared deviation of the scores from the mean



standard score	deviation of a raw score from the mean in standard deviation units; also known as a z score



z score	deviation of a raw score from the mean in standard deviation units; also known as a standard score

2003 McGraw-Hill Higher Education
Any use is subject to the Terms of Use and Privacy Notice.
McGraw-Hill Higher Education is one of the many fine businesses of The McGraw-Hill Companies.