Chapter 3 (3.5-3.7)

Question 1

What’s the unit of observation in individual-level analyses?

Answer 1

Individuals.

Question 2

What’s the unit of observation in aggregate-level analyses?

Answer 2

Collections of individuals.

Question 3

True or false: 0 = no linear association.

Answer 3

True

Question 4

True or false: 1 = linear association.

Answer 4

True

Question 5

What does the term “z-score” refer to?

Answer 5

The number of standard deviations the observation is above or below the mean.

Question 6

What does it mean if two variables have a correlation coefficient of 0?

Answer 6

That there’s no linear relationship between them.

Question 7

Explain the following sentence: “correlation does not equal causation”.

Answer 7

Just because two variables are (highly) correlated with each other doesn’t mean that changes in one of the variables results in changes in the other variable.

Question 8

How do you explore the relationship between two variables?

Answer 8

By creating scatter plots and computing correlation coefficients.

Question 9

True or false: if the correlation coefficient between “X” and “Y” is greater than 0, the slope of the line of best fit is negative.

Answer 9

False

Question 10

True or false: if the correlation coefficient between “X” and “Y” is lower than 0, the slope of the line of best fit is positive.

Answer 10

False