Chapter 9 - Multivariate Correlational Research

Question 1

define third variable

Answer 1

variable that accounts for the apparent association between your town variables of interest. once taken into account, the variables can no longer be related

Question 2

define moderating variables

Answer 2

a variable (theoretical interest) that influences or changes the nature of the relation between two other variables. you see a different pattern of association, weak at one level of moderator and strong at another level

Question 3

what are the 2 things that multivariate research can address?

Answer 3

temporal precedence and internal validity (by identifying thrid variables)

Question 4

define longitudinal designs

Answer 4

measuring the same varaibles in the same people over a long period of time

Question 5

what are the 3 correlations that can be made from longitudinal designs?

Answer 5

X1 and X2: autocorrelations, (correlation of one varibles with itself, measured at two different times)
X1 with Y1: only at one time, cross section correlation (correlation between two variables that are measured at the same time)
X1 and Y2, X2 and Y1: cross-lag correlation, time difference/lag between the variables (correaltion between earlier measure of one variables and a later measure of another variable)

Question 6

how can you rule out third variables?

Answer 6

they can be controlled for by adding the suspected third variables (control variables) into the analysis

there is still only 1 outcome variable, but now you have an infinite amount of predictor variables

Question 7

what does Beta signify?

Answer 7

it is very similar to r but it does not have a specific range
- it gives an estimate change in relation of y for x
- holds all other predictor variables constant

Question 8

how can mutliple regression still not establish causation?

Answer 8

1. cannot establish temporal precendence: need to have longitudinal studies for this
2. can never control everything: still so many variables that are not measured that can still affect your results

Question 9

define mediation

Answer 9

answers the questions of why X has a causal effect of Y. it is a internal mechanism that is in the middle of x and y

explains the relationship between the 2 varibales

Question 10

what is teh difference between a medaitor and a moderator?

Answer 10

mediator: caused by x to cause y (why does x influence y)
moderator: changes strength at different levels between x and y (how does the association change when the level of the variables changes)

Question 11

define modertor

Answer 11

it is an external variables that cahnges the original relationship between x and y, the relationship is different at different levels of the moderator

Question 12

define multiple regression

Answer 12

statistical technique that computes the relationsip between a predictor and criterion/outcome variables, while controlling for other predictor variables

Question 13

define controlling a variable

Answer 13

holding a potential third variable at a constant elve while looking at the association between two other variables

Question 14

define criterion variable

Answer 14

varaibles in teh regression that the researchers are most interested in understanding

Question 15

define predictor variable

Answer 15

variable that is used to explain variance in the criterion variable