Bivariate Techniques

Question 1

_________________________ are used to describe the degree of association between two or more variables (i.e., the degree to which two or more variables co-vary).

Answer 1

Correlational techniques.

Question 2

The X (IV) is refered to as the _____________________, while the Y (DV) is the ___________________.

Answer 2

• Predictor
• Criterion

Question 3

__________________ are used to summarize the degree of association between 2 variables.

Answer 3

Bivariate techniques.

Question 4

The degree of association for 2 variables can be depicted in a __________________, in which the X (predictor) is placed on the horizontal axis, and the Y (criterion) is located on the vertical axis. When there is a narrow scatter of data points, this indicates a strong relationship.

Answer 4

Scattergram.

Question 5

A ___________________ summarizes the degree of association between variables with a single number. Selection is based on the ________________ of the variables being correlated.

Answer 5

• Correlation coefficient
• Scale of measurement

Question 6

______________________ (a.k.a. _____________ Product Moment Correlation Coefficient):

• Variable 1: Interval or ratio
• Variable 2: Interval or ratio
• Range: -1.0 to 1.0 (perfect negative to perfect positive correlation).

Answer 6

• Pearson r
• Pearson

Question 7

____________________ (a.k.a. ______________ Rank-Order Correlation Coefficient):

• Variable 1: Rank-ordered
• Variable 2: Rank-ordered

Answer 7

• Spearman rho
• Spearman

Question 8

________________:

• Variable 1: True dichotomy
• Variable 2: True dichotomy

Answer 8

Phi.

Question 9

_____________________:

• Variable 1: Artificial Dichotomy
• Variable 2: Artificial Dichotomy

Answer 9

Tetrachoric.

Question 10

______________________:

• Variable 1: Nominal
• Variable 2: Nominal

Answer 10

Contingency.

Question 11

______________________:

• Variable 1: True dichotomy
• Variable 2: Interval or ratio

Answer 11

Point Biserial.

Question 12

_______________:

• Variable 1: Artificial dichotomy
• Variable 2: Interval or ratio

Answer 12

Biserial.

Question 13

______________: Used when the relationship between variables is nonlinear.

• Variable 1: Interval or ratio
• Variable 2: Interval or ratio

Answer 13

Eta.

Question 14

Correlation coefficients require that ___ assumptions be met.

Answer 14

3.

Question 15

__________________: The relationship between X and Y can be summarized by a straight line. If this is not true, the Pearson r will underestimate the degree of association.

Answer 15

Linearity.

Question 16

______________________: The data have been collected from people who are heterogenous with regard to the characteristics measured by X and Y. If this is not met, the Pearson r is likely to be an underestimate.

Answer 16

Unrestricted range.

Question 17

_____________________: The range of Y scores is about the same for all values of X. If this is not met, a coefficient may be produced that does not represent the full range of scores.

Answer 17

Homoscedasticity.

Question 18

A correlation coefficient can be interpreted directly in terms of __________________; the closer to -1 or +1, the stronger the association; the closer to 0, the weaker the association.

Answer 18

Degree of association.

Question 19

Whenever a correlation coefficient represents the degree of association between two different variables, it can be squared to obtain a ______________________, which provides a measure of shared variability.

e.g., If the correlation coefficient for two variables is .60, then 36% (0.6² = 0.36) of the variability in one variable is accounted for by the other variable.

Answer 19

Coefficient of determination.

Question 20

When a correlation coefficient is a reliability coefficient, it is ______________ squared.

Answer 20

Never.

Question 21

___________________: The correlation coefficients can be evaluated to determine if they are statistically significant by comparing the obtained coefficient to the appropriate critical value. The magnitude of the critical value is determined by alpha and the sample size; the ___________ the sample, the _____________ the correlation coefficient must be to be statistically significant.

Answer 21

• Hypothesis testing
• Smaller
• Larger

Question 22

______________________ is the technique that allows a predictor (X) to estimate performance on a criterion (Y).

Answer 22

Regression analysis.

Question 23

The technique used to find the regression line in a scatterplot is referred to as the ____________________, which locates the line so that the amount of error in prediction is minimized.

Answer 23

Least squares criterion.