113-2 Ｂ班統計期中複習

1. Compared to independent-measures designs, repeated-measures designs reduce the variance by removing individual differences.

• O

• X

1. An independent-measures study with n = 20 scores in each condition will

produce an independent-measures t statistic with df = 18.

• O

• X

The correct alternative hypothesis for a one-tailed repeated-measures t test is

μ ≠ 0

• O

• X

1. A matched-subjects research design is a type of repeated-measures research design because the participants in each treatment condition are the same people.

• O

• X

1. One advantage of a repeated-measures research design is that it typically requires fewer participants than an independent-measures design.

• O

• X

Which of the following is the correct null hypothesis for an independent-measures t test?

• μ1-μ2≠0

• M1-M2≠0

• μ1-μ2=0

• M1-M2=0

An independent-measures research study uses n = 15 participants in one group

and n = 12 participants in a second group to compare two treatment conditions.

What is the df value for the t statistic computed for the corresponding hypothesis test?

• df=27

• df=24

• df=25

• df=26

An independent-measures study comparing two treatment conditions produces a t

statistic with df = 16. If the two samples are the same size, how many participants

were in each of the samples?

• n=9

• n=10

• n=8

• n=18

A researcher uses a repeated-measures study to compare two treatment conditions with a set of 20 scores in each treatment. What is the value of df for the repeated-measures t statistic?

• df=18

• df=19

• df=38

• df=39

The narrower the confidence interval, the more precise it is. Which combination of factors will produce the most precise estimate of the difference between two population means?

• 1. two samples of n = 20 and 80% confidence

• 1. two samples of n = 20 and 90% confidence

• 1. two samples of n = 50 and 80% confidence

• 1. two samples of n = 50 and 90% confidence