Flashcards in Stats 2 Third Exam Deck (51)

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1

## What does Repeated Measures ANOVA / "Within Subjects Design" do?

### Test to see if responses change over time OR Test significance between multiple simultaneous responses on the same item

2

## What is most common within subjects design?

### Pre-Post Design: O X O

3

## Pre-post statistical test sometimes called

###
"Dependent t test" This is inaccurate.

Called "Dependent Test of Means"

4

##
What are the issues with within subjects designs?

###
* Same people responding -- impacts our measurements

* Individuality differences

* Start separating out error terms

5

## What comprises a Repeated Measures ANOVA Model?

###
* 1 fixed categorical (dependent) IV with 2 levels that will be repeated

* 1 continuous random DV measured multiple times

6

## What are assumptions of Repeated Measures designs?

###
* R - random selection (not random assignment)

* N - Normality of error term

* H - Homogeneity of variance

* D - Dependence (not independence)

7

## What are potential methods of analysis for within subjects designs?

###
1. Multiple dependent t tests

2. Gain scores

3. ANCOVA

4. Univariate repeated measures

5. Adjusted univariate repeated measures

6. Multivariate repeated measures

8

## Defining features of gain scores approach to analysis in within subjects design?

###
1. Frequently used in pre-post

2. Issues:

a. Reliability issues

b. Alpha issues

c. However, Observed score is true score + error

d. Assumes same reliability across measurements

9

## Defining features of ANCOVA approach to analysis in within subjects design?

###
1. No test of time

2. Violates assumption of independence (it's the very thing we want to test)

10

## Defining features of Univariate repeated measures approach to analysis in within subjects design?

### Requires new assumption: Sphericity (symmetry)

11

## What is assumption of sphericity?

###
1. Deals with correlations among variables

2. Assumes correlation matrix will have equivalent values within it

12

## Defining features of Adjusted univariate repeated measures approach to analysis in within subjects design?

###
1. Adjusts for symmetry (through degrees of freedom)

2. Employs multiple tests (experimentwise alpha considerations)

13

## Defining features of Multivariate repeated measures approach to analysis in within subjects design?

###
1. Allows for non-symmetry

2. Controls alpha

3. One test

14

## What are implications of testing the assumption of syphericity (Mauchly test)

###
1. If meets symmetry, univariate approach

2. If does not, multivariate approach

15

## What are three types of repeated measures?

###
1. Time

2. Response mode

3. Persons unit (e.g., family)

16

## What is a twice repeated design?

###
1) Pre-post-follow up.

2) Unit pre-post

17

## In repeated measures, what are implications of unequal n?

### Cannot work with unequal n. Excluded participants with missed observations.

18

## What are defining features of repeated measures error terms?

### Every factor and every interaction has its own error term.

19

## Class example of a 2x2 fully repeated design

### Child-parent, pre-post

20

## What are defining features of a mixed model design?

###
* 1 fixed categorical IV (between subjects)

* 1 fixed categorical repeated IV (within subjects)

* 1 continuous random DV

21

## In an # x # mixed model design, 1st number represents

### Non-repeated factor

22

## In a # x # mixed model design, 2nd number represents

### Repeated factor

23

## In a # x # x # mixed model design, 2nd number represents

###
* 1st refers to non-repeated factor

* 3rd refers to repeated factor

* Nothing in our language denotes what middle number represents

24

## What are assumptions of mixed model designs?

###
* Homogeneity

* Independence for some IVs

* Dependence for some IVs

25

## Effect size for mixed model design?

### Eta squared or partial eta squared

26

## Eta squared

### SSH/SST

27

## Partial eta squared

### SSH/SSH+SSE

28

## What is the relation between eta squared and partial eta squared?

###
Partial eta squared gives higher value and thus overestimates strength of association.

Eta squared is a more conservative estimate.

29

## What assumptions do you check in a mixed model design?

### Homogeneity and sphericity first.

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