PSYC 2021 Study Guide - Midterm Guide: Standard Deviation, Bias Of An Estimator, Variance

• School: York University
• Department: Psychology
• Course: PSYC 2021
• Professor: Margarete Wolfram

Document Summary

Goal in stats is to measure the amount of variability for a particular set of scores, a distribution. If all the scores are the same, theres no variability. Variability: the differences b/w scores and describes how dif. 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. It tells us if scores are closer together or more spread out (usually in terms of distance) It tells us how much distance to expect between a score and another. 3 dif measures of variability: the range. Distance covered by the scores in a distribution, from the smallest score to the largest score. Range = xmax xmin eg. values 1-5 have a range of 4. De(cid:272)i(cid:373)al ra(cid:374)ges are usuall(cid:455) (cid:862)(cid:1005)(cid:863) si(cid:374)(cid:272)e the ra(cid:374)ge is (cid:1004)-1. For continuous variables, the range is the difference between the url and the lrl: url for xmax lrl for xmin = range.