Class Notes (837,534)
Canada (510,303)
Psychology (3,336)
PSYC 305 (53)
Lecture 7

Lecture 7 - Jan 30.doc

3 Pages
134 Views
Unlock Document

Department
Psychology
Course
PSYC 305
Professor
Heungsun Hwang
Semester
Winter

Description
PSYC305 Lecture 8 - Feb. 1 One-Way ANOVA: • Purpose: • To test whether the means of k (≧ 2) populations significantly differ • H 0 µ1 = µ2 … = µk • H 1 Not all µ’s are the same (at least one of the means is different) • Example: One-Way ANOVA The statistics classroom is divided into three rows: front, middle, and back • • The instructor noticed that the further the students were from him, the more likely they were to miss class or use an instant messenger during class • He wanted to see if the students further away did worse on the exams • DV = Exam score • Factor (IV) = Class row • Three levels: front, middle, and back • H 0 µ1 = µ2 = µ3 • H 1 Not all µ’s are the same • In this example, the critical value for a = .05 is 3.47 with df(B) = 2 and df(W) = 21 • F (.05, 2, 21) = 3.47 • The null hypothesis may be rejected because you F value (5.9) > 3.47 • We may thus conclude that where students sit in the stats class has a significant effect on their mid- term exam scores (F (2, 21) = 5.9, p < .05). Also this effect is large (r = .54) One-Way ANOVA: • When the null hypothesis is rejected in ANOVA, it suggests that there is at least one pair of group means is different • Then, we may want to know which pairs of group means are significantly different • µ1≠ µ 2 • µ1≠ µ 3 • µ2≠ µ 3 • F=test gives a global effect of the independent variable (factor) on the dependent variable (om- nibus or overall test) Doesn’t tell which pairs of means are different • • We need to perform post hoc comparison tests to determine this • Post hoc (a posterior/unplanned) comparisons • Decided upo
More Less

Related notes for PSYC 305

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit