1.

A description of different houses on the market includes the following three variables. Which of these variables is interval variable?

A)

The square footage of the house

B)

The monthly gas bill

C)

The monthly electric bill

D)

All of the above

2.

We have a data set where the observations are college students. One of the variables in the data set is "gender." The values of gender are 1 if the student is male and 2 if the student is female. What type of variable is gender?

A)

Nominal

B)

Ordinal

C)

Interval

D)

None of the above

3.

What are the possible ways of increasing reliability for a measurement?

A)

Use an objective measure

B)

Provide rigorous training to researchers

C)

Employ multiple researchers to measure the same phenomenon

D)

All of the above

4.

Which statement explains the criterion ofcovariationin determining a causal relationship?

A)

If variable A is the cause of variable B, A must precede B in time.

B)

The association between two variables cannot be explained by a third factor.

C)

Changes in variable A lead to changes in variable B.

D)

There should be a theoretical explanation for this causal relationship.

5.

A consumer agency is testing appliances for a series of articles in their magazine. Currently they are working with cooktops and ranges. They have selected 16 of the most commonly used models. Using a series of tests, the agency will estimate the lifetime of these models. A histogram of these (estimated) lifetimes is shown below.

Select the correct description for the shape of the histogram of the estimated lifetimes of these 16 appliances.

A)

Symmetric

B)

Bimodal

C)

Skewed right

D)

Skewed left

6.

The salaries of Major League Baseball players range from several hundred thousand dollars per year to many millions per year. Suppose a histogram is made of all last year's salaries of Major League Baseball players. Which shape would best describe the shape of this histogram?

A)

Skewed to the left

B)

Bell-shaped

C)

Skewed to the right

D)

Symmetric