paired vs diff on means t test

To test the effect of background music on productivity, factory workers are observed. For one month, each subject works without music. For another month, the subject works while listening to music on an MP3 player. The month in which each subject listens to music is determined by a coin toss.

What kind of test should be used?

• Paired t-test

• Difference of means test

A study was designed to compare the effectiveness of two weight-reducing diets. Fifty obese women who volunteered to participate were randomly assigned into two equal-sized groups. One group used Diet A and the other used Diet B. The weight of each woman was measured before the assigned diet and again after 10 weeks on the diet.

What kind of test should be used?

• Paired t-test

• Difference of means test

To test the wear characteristics of two tire brands, A and B, each brand of tire is randomly assigned to 50 cars of the same make and model. (Two tires of each brand are randomly assigned to either the left or the right side of each car)

What kind of test should be used?

• Paired t-test

• Difference of means test

Tags

CCSS.HSS.IC.B.3

To compare the average weight gain of pigs fed two different rations, nine pairs of pigs were used. The pigs in each pair were littermates. A coin toss was used to decide which pig in each pair got Ration A and which got Ration B.

What kind of test should be used?

• Paired t-test

• Difference of means test

Tags

CCSS.HSS.ID.A.4

A random sample of college professors is taken. We wish to compare the average salaries of male and female teachers.

What kind of test should be used?

• Paired t-test

• Difference of means test

To test the effects of a new fertilizer, 100 plots are treated with the new fertilizer, and 100 plots are treated with the old fertilizer. A computer’s random number generator is used to determine which plots get which fertilizer.

What kind of test should be used?

• Paired t-test

• Difference of means test

Tags

CCSS.7.SP.B.4