Correlation/Regression

Question 1

Variable outliers

Answer 1

Extreme on variables, but lie along regression line

Question 2

Regression outliers

Answer 2

Far away from regression line

Question 3

Influential outlier

Answer 3

Regression outlier and towards the low or high end of a variable
Including it would cause a change in the slope of the regression line

Question 4

Strength of correlation

Answer 4

Strong: close to 1 (0.8 or more)
Weak: close to 0 (0.4 or less)
Exactly 0: no correlation

Question 5

Interpreting scatter plots

Answer 5

1. Outliers (type, location)
2. Direction of correlation (positive or negative)
3. Strength of correlation

Question 6

Residual

Answer 6

Actual y minus y hat (predicted value of y)

Difference between a single point and the line

Question 7

R^2

Answer 7

Proportion of y that is explained by x

Question 8

Contingency table

Answer 8

Categorical data

Can analyze data by row, column, or from total