Key Concepts

Question 1

Define Effect Size

Answer 1

Tells us how many standard devations two means differ by, independent of sample size

Can be measured through Cohens D

Question 2

Define Type I Errors

Answer 2

False Positive

Question 3

Define Type II Errors

Answer 3

False Negative

Question 4

Define Statistical Power

Answer 4

The probability of avoiding a Type II Error : should aim for 0.8 (COHEN)

Question 5

Define Power Analysis

Answer 5

A method used to calculate the minimum number of participants based on desired power and anticipated effect size

Question 6

Define F Ratio

Answer 6

A ratio of the varience in a DV that can be explained by MS between to varience in the DV that cannot be explained through MS within

F = MSbetween / MSwithin

Question 7

Define Repeated Designs

Answer 7

An experimental design where the same participants take part in each condition of the experiment

Question 8

Define Experimental Designs

Answer 8

Looking for a cause and effect relationship

Question 9

What factors affect power?
() = better

Answer 9

1. Sample Size (large)
2. Effect Size (large)
3. Experimental (repeated measures)
4. Alpha Level (less strict)

Question 10

What does the P Value Tell us

Answer 10

The probability of observing the data you collected if the null hypothesis is true

Question 11

How is Cohen’s d calculated?

Answer 11

d = (m Group 1 - m Group 2) / Pooled SD

Question 12

What are classified as small, medium, and large effect sizes using Cohen’s d?

Answer 12

Small = around 0.2
Medium = around 0.5
Large = around 0.8