Exam 4

Question 1

Pearson Correlation

Answer 1

Measures the degree and the direction of the linear relationship between two variables.
r=degree to which X and Y vary together/degree to which X and Y vary separately

Question 2

Sum of Products of Deviations (conceptual)

Answer 2

SP= Sum of XY-(Sum of X)(Sum of Y)/n

Question 3

Coefficient of Determination

Answer 3

r squared
Measures the proportion of variability in one variable that can be determined from the relationship with the other variable.

Question 4

Partial Correlation

Answer 4

Measures the relationship between two variables while controlling the influence of a third variable by holding it constant.

Question 5

Regression

Answer 5

The statistical technique for finding the best-fitting straight line for a set of data. The resulting straight line is called the regression line.

Question 6

Standard Error of Estimate

Answer 6

Gives a measure of the standard distance between a regression line and the actual data points.

Question 7

Three Conditions for Pearson’s r

Answer 7

1) Both variables are quantitative in nature AND measured on at least the interval level
2) X ( predictor, IV) and Y (criterion, DV) have been measured on the same individuals
3) Observations on each variable are between-subjects

Question 8

Interpreting r

Answer 8

\+/- .80-1.00 very strong
\+/- .60-.79 strong
\+/- .40-.59 moderate
\+/- .20-.39 weak
\+/- .00-.19 very weak

Question 9

Coefficient of Nondetermination

Answer 9

k or (1-r squared)

Question 10

Interpreting r squared

Answer 10

.50 strong
.30 moderate
.10 weak