Final Test

Question 1

What are mediation and moderation all about?

Answer 1

Relationships among three or more variables

Question 2

What is mediation about?

Answer 2

The mechanism

Question 3

The basic relationship

Answer 3

Between the predictor variable and outcome variable. Path c.

Question 4

The a path

Answer 4

Between predictor variable and mediating variable.
The first regression: Unstandardized coefficients B and Std. Error
A value is beta

Question 5

The b path

Answer 5

Two predictors (independent and mediating) on the dependent variable. Goal is B and SE for mediating variable on dependent.
The second regression: Unstandardized coefficients B and SE – makes sure it’s mediating row
: Standardized coefficients Beta weights for both predictors
B value is beta
Also collect number from zero order correlations

Question 6

The direct effect

Answer 6

C prime. the beta between IV and DV when the MedV is included

Question 7

What is a confidence interval?

Answer 7

An attempt to create a range that captures the amount of variability of that estimate. If the CI does not include the value of zero then it is statistically significant.

Question 8

Standardised indirect effect

Answer 8

A times B. It is NOT a multiplication of the zero-order correlations because the second correlation does not reflect the presence of the other variable

Question 9

The total effect mediation

Answer 9

the beta or raw correlation between the IV and the DV, c prime

Question 10

Indirect to total ratio:

Answer 10

Indirect divided by total, answer is a percentage. Ratio scores are zero to 100. % of the basic relationship between the IV and the DV is explained by the indirect effect, unexplained is rest of ratio.

Question 11

Multiple mediator model

Answer 11

Cannot be done with simple regression but done with structural equation modelling. Amos loaded with SPSS

Question 12

Variable types in mediation

Answer 12

Typically done with three continuous variables, can also do when IV is dichotomous.
Can do mediation when either or both the MedV and DV is dichotomous, but this requires logistic regression, and it’s complicated.

Question 13

Wald’s Test

Answer 13

The Wald’s test is like the F-test or t-test: The Exp(B), also known as the odds ratio, represents the probability that this particular outcome will occur.
Key point: The B and se are on a different scale than in linear regression

Question 14

Longitudinal mediation

Answer 14

C prime path between IV1 and DV3
A path between IV1 and MV2
B path between MV2 and DV3

Question 15

What is moderation about?

Answer 15

Moderation looks at associations of variables within groups (WHO), do different groups have different relationships between the IV and DV

Question 16

Similarities between mediation and moderation

Answer 16

At the basic level, both involve 3 variables
Both can be done with ordinary regression in SPSS
Both examine the impact of a third variable on a 2-variable relationship

Question 17

Differences between mediation and moderation

Answer 17

Moderation features an interaction (two Ivs are multiplied) term
Moderation is not a causal model
IV and ModV do not need to be correlated in moderation
Graphing is important in moderation

Question 18

How do we do a moderation?

Answer 18

An interaction term is added to the basic model (on top of the 2 main effects) - regression with three predictors. So we have Iv, ModV and IV*ModV all leading to DV

Question 19

Constraints on regression based moderation

Answer 19

IV: Must be continuous
ModV: May be continuous or categorical
DV: Must be continuous

Question 20

Dummy coding basics

Answer 20

Dummy coding - must have a zero code.
You will have one less dummy variable than the number of categories.
You need to designate one category as the ‘comparison’ group
(all zeros)
Be sure that the ‘absence’ code is zero.

Question 21

Interaction term in moderation

Answer 21

Multiply IV by ModV to create the new variable

Question 22

Placement of variables when graphing moderation

Answer 22

IV is across on x axis
DV is up on y axis
ModV: Lines depict the slopes of the groups, slopes indicate the direction and strength of the association

Question 23

Interpreting simple slopes!

Answer 23

Look at simple slope values and p values

Question 24

What did Aiken and West have to say?

Answer 24

They argued that centring the IV and ModV before multiplying them to create the interaction term was advantageous. It has now become ‘standard practice’.
Centring is subtracting the mean of a variable from all scores on that variable. Yields a mean of zero and the same SD.

Question 25

What did Kromrey and Foster-Johnson have to say?

Answer 25

They showed that centring has no impact on the significance of the interaction term nor on the graphed pattern of the moderation result

Question 26

Moderation: Buffer

Answer 26

the moderator fosters lower levels of the negative DV. Highest level of moderator is flattest slope.

Question 27

Moderation: Exacerbator

Answer 27

the moderator fosters higher levels of the negative DV. Lowest level of moderator is flattest slope.

Question 28

Moderation: Enhancer

Answer 28

the moderator fosters higher levels of the positive DV. Lowest level of moderator is flattest slope.

Question 29

Moderation: Dampener

Answer 29

the moderator fosters lower levels of the positive DV. Highest level of moderator is flattest slope.

Question 30

Things to avoid doing in moderation

Answer 30

A failure to properly dummy-code categorical ModVs;
Confusion about what types of variables are proper ModVs;
Inaccurate graphing of the interaction result (in whatever graphing facility that you use);
Unfamiliarity with simple slope analyses;
Inexperience with making interpretations of moderation results; and
An inclination to use causal language in interpretation.

Question 31

What is a quadratic polynomial?

Answer 31

A quadratic polynomial is the same thing as the IV moderating itself. In essence, it tells us that the slope of the association between the IV and the DV changes depending on the value of the IV, i.e., it’s not a constant slope.

Question 32

Types of moderation

Answer 32

Linear moderation: X and Y and Z
A Quadratic: X2 and Y
Quadratic Moderation: X and Y and Z2
Moderation of a quadratic: X2 and Y and Z