Flashcards in Chapter 8 Deck (20):

1

## Bivariate correlations

###
associations that involve exactly two variables

also called bivariate associations

2

## R value

### Correlation coefficiant

3

## T test

###
Statistic to test the difference between two group averages

It is still possible to calculate an r value, but a t test is more commonly used.

4

## What makes a study correlational?

### Having two measured variables, using either a bar graph of scatter plot

5

## Construct Validity

### How well was each variable measured

6

## Statistical Validity

### How do the data support the conclusion

7

## Internal Validity

### Can we make a casual inference frmo association?

8

## External validity

### To whom can the association be generalized?

9

## Effect size

###
describes the strength of an association.

How close they stick to a line

10

## Statistical significance

###
didn’t find the result by chance.

refers to the conclusion researchers make regarding how probable it is that they would get a correlation of that size by chance, assuming that there is not a correlation in the real world

11

## P value

###
Probability estimate

Provides information about statistical significance by evaluation the probability that the association in the sample came form a population with an association of zero

dependent on sample size and effect size.

12

## Outlier

### An extreme score

13

## Restriction of range

###
When there is not a full range of scores on one of the variables in an association in a correlational study, it can make the correlation appear smaller than it really is.

14

## Curvilinear association

### Correlation Coefficient is zero (or close to zero), and the relationship isn’t a straight line.

15

##
The Three Criteria for Establishing Causation

### Covariance, Temportal precedence ( the directionality problem), Internal validity (third-variable problem)

16

## Covairiance

###
There must be an association between the cause variable (A) and the effect variable (B).

17

## Temporal precedence (the directionality problem):

###
The causal variable (A) must come before the effect variable (B).

18

## Internal validity (third-variable problem)

### Is there a third variable (C) that is associated with variables A and B independently? If so, then we can’t infer causation.

19

## spurious association

### one that is only present because of a third variable

20