Chapter 2: Correlation

Question 1

Correlation:

Answer 1

When the change in one variable is synchronized to the changes in the other variable.

Correlation has direction and strength.

Question 2

Natural correlations:

Answer 2

Correlations we simply see in the world.

Question 3

Third variable:

Answer 3

Z causing X & Y.

Question 4

Third variable: Prevention methods:
1.
2.
3.

Answer 4

1. Manipulating the independent variable.
2. Randomly assigning participants to a condition.
3. Measuring the dependent variable.

Question 5

Correlation coefficient: Direction of a correlation: Positive: +r:

Answer 5

“more is more”

Question 6

Correlation coefficient: Direction of a correlation: Negative: -r:

Answer 6

“more is less”

Question 7

Strength of a correlation: Range (r):

Answer 7

-1 to +1

Question 8

Strength of a correlation: Range (r) = 1

Answer 8

Perfect positive correlation: When one value increases by a certain amount, the other predictably increases by a certain amount.

Question 9

Strength of a correlation: Range (r) = 0

Answer 9

No correlation = When one variable changes, sometimes the other increases or decreases, or does not change at all.

Question 10

Strength of a correlation: Range (r) = -1

Answer 10

Perfect negative correlation: When one value increases by a certain amount, the other predictably decreases by a certain amount too.