PSYC 2021 Study Guide - Final Guide: Type I And Type Ii Errors, Null Hypothesis, Round-Off Error

• School: York University
• Department: Psychology
• Course: PSYC 2021
• Professor: Edward Haltrecht

Document Summary

If the numerator is sufficiently bigger than the denominator, we conclude that there is a significant difference between treatments: a. As the differences between sample means increase, msbetween also increases, and the f: with 3 or more treatment conditions, you need three or more t tests to evaluate all the mean differences. Each test involves a risk of a type i error. The more tests you do, the more risk there is of a type i error. The anova performs all of the tests simultaneously with a single, fixed alpha level: a. posttests are used to determine exactly which treatment conditions are significantly, a. The three means produce ss = 14. b. n(ssmeans) = 140 c. ssbetween = 140: a. Between treatments 84 2 42 f(2, 15) = 6. 00. Reject the null hypothesis and conclude that there are significant differences among the three treatments: 2 = 84/189 = 0. 444, analysis of variance showed significant mean differences among the three treatments,