Question 1

The results of a hypothesis test are reported as follows: t(15) = 2.70,p < .05.Based on this report,how many individuals were in the sample?​

Accepted Answer

A)  ​14
B)  ​15
C)  ​16
D)  ​17

Question 2

What is the sample variance and the estimated standard error for a sample of n = 9 scores with SS = 72?​

Accepted Answer

A)  ​s2 = 9 and sM = 3
B)  ​s2 = 9 and sM = 1
C)  ​s2 = 3 and sM = 3
D)  ​s2 = 3 and sM = 1

Question 3

A sample of n = 25 scores has a mean of M = 65 and an estimated standard error of 2 points.What is the sample variance?​

Accepted Answer

A)  ​s2 = 100
B)  ​s2 = 96
C)  ​s2 = 50
D)  ​s2 = 48

Question 4

A hypothesis test with a sample of n = 25 participants produces a t statistic of t = +2.53.Assuming a one-tailed test with the critical region in the right-hand tail,what is the correct decision?​

Accepted Answer

A)  ​The researcher can reject the null hypothesis with α = .05 but not with α = .01.
B)  ​The researcher can reject the null hypothesis with either α = .05 or α = .01.
C)  ​The researcher must fail to reject the null hypothesis with either α = .05 or α = .01.
D)  ​It is impossible to make a decision about H0 without more information.

Question 5

In order to estimate a population mean with a confidence interval,you first must estimate a range of values for t.

Accepted Answer

A) True 
 B)False

Question 6

Two samples are selected from a population and a treatment is administered to the samples.If both samples have the same mean and the same variance,you are more likely to find a significant treatment effect with a sample of n = 100 than with a sample of n = 4.

Accepted Answer

A) True 
 B)False

Question 7

If other factors are held constant,which set of sample characteristics is most likely to reject a null hypothesis stating that m = 80?​

Accepted Answer

A)  ​M = 85 and small sample variance
B)  ​M = 85 and large sample variance
C)  ​M = 90 and small sample variance
D)  ​M = 90 and large sample variance

Question 8

A research report states "t(15)= 2.31,p < .05." For this study,the sample had n = 16 scores.

Accepted Answer

A) True 
 B)False  True

Question 9

A sample of n = 4 scores is selected from a population with an unknown mean.The sample has a mean of M = 40 and a variance of s2 = 16.Which equation correctly describes the 90% confidence interval for μ?​

Accepted Answer

A)  ​μ = 40 ± 2.353(4) 
B)  ​μ = 40 ± 1.638(4) 
C)  ​μ = 40 ± 2.353(2) 
D)  ​μ = 40 ± 1.638(2)

Question 10

With α = .05,what is the critical t value for a one-tailed test with n = 15?​

Accepted Answer

A)  ​t = 1.761
B)  ​t = 1.753
C)  ​t = 2.145
D)  ​t = 2.131

Question 11

If a hypothesis test using a sample of n = 16 scores produces a t statistic of t = 2.15,then the correct decision is to reject the null hypothesis for a two-tailed test with a = .05.

Accepted Answer

A) True 
 B)False

Question 12

If other factors are held constant,as the sample variance increases,the estimated standard error also increases.

Accepted Answer

A) True 
 B)False

Question 13

As sample size increases,the critical region boundaries for a two-tailed test with a = .05 will move closer to zero.

Accepted Answer

A) True 
 B)False  True

Question 14

Why are t statistics more variable than z-scores?​

Accepted Answer

A)  ​The extra variability is caused by variations in the sample mean.
B)  ​The extra variability is caused by variations in the sample variance.
C)  ​The extra variability is caused by variations in the df value.
D)  ​The extra variability is caused by the large sample size.

Question 15

A sample of n = 16 scores with a sample variance of s2 = 64 would have an estimated standard error of 4 points.

Accepted Answer

A) True 
 B)False

Question 16

If two samples are selected from the same population,under what circumstances are the two samples guaranteed to have exactly the same t statistic?​

Accepted Answer

A)  ​If the samples are the same size and have the same variance
B)  ​If the samples are the same size and have the same mean
C)  ​If the samples have the same mean and the same variance
D)  ​If the samples are the same size and have the same mean and have the same variance

Question 17

A researcher conducts a hypothesis test using a sample from an unknown population.If the t statistic has df = 35,how many individuals were in the sample?​

Accepted Answer

A)  ​n = 34
B)  ​n = 35
C)  ​n = 36
D)  ​n=32

Question 18

A sample of n = 4 scores with SS = 48 has a variance of 16 and an estimated standard error of 2.

Accepted Answer

A) True 
 B)False

Question 19

With α = .05 and df = 8,the critical values for a two-tailed t test are t = ±2.306.Assuming all other factors are held constant,if the df value were increased to df = 20,what would happen to the critical values for t?​

Accepted Answer

A)  ​They would increase (move farther from zero) .
B)  ​They would decrease (move closer to zero) .
C)  ​They would stay the same.
D)  ​There is not enough information to answer.

Question 20

A research report states "t(8)= 2.00,p > .05." For this test,r2 = 2/10.

Accepted Answer

A) True 
 B)False  False

Exam 9: Introduction to the T Statistic

The results of a hypothesis test are reported as follows: t(15) = 2.70,p < .05.Based on this report,how many individuals were in the sample?​

Correct AnswerverifiedShow Answer

What is the sample variance and the estimated standard error for a sample of n = 9 scores with SS = 72?​

Correct AnswerverifiedShow Answer

A sample of n = 25 scores has a mean of M = 65 and an estimated standard error of 2 points.What is the sample variance?​

Correct AnswerverifiedShow Answer

A hypothesis test with a sample of n = 25 participants produces a t statistic of t = +2.53.Assuming a one-tailed test with the critical region in the right-hand tail,what is the correct decision?​

Correct AnswerverifiedShow Answer

In order to estimate a population mean with a confidence interval,you first must estimate a range of values for t.

Correct AnswerverifiedShow Answer

Two samples are selected from a population and a treatment is administered to the samples.If both samples have the same mean and the same variance,you are more likely to find a significant treatment effect with a sample of n = 100 than with a sample of n = 4.

Correct AnswerverifiedShow Answer

If other factors are held constant,which set of sample characteristics is most likely to reject a null hypothesis stating that m = 80?​

Correct AnswerverifiedShow Answer

A research report states "t(15)= 2.31,p < .05." For this study,the sample had n = 16 scores.

Correct AnswerverifiedTrue

A sample of n = 4 scores is selected from a population with an unknown mean.The sample has a mean of M = 40 and a variance of s2 = 16.Which equation correctly describes the 90% confidence interval for μ?​

Correct AnswerverifiedShow Answer

With α = .05,what is the critical t value for a one-tailed test with n = 15?​

Correct AnswerverifiedShow Answer

If a hypothesis test using a sample of n = 16 scores produces a t statistic of t = 2.15,then the correct decision is to reject the null hypothesis for a two-tailed test with a = .05.

Correct AnswerverifiedShow Answer

If other factors are held constant,as the sample variance increases,the estimated standard error also increases.

Correct AnswerverifiedShow Answer

As sample size increases,the critical region boundaries for a two-tailed test with a = .05 will move closer to zero.

Correct AnswerverifiedTrue

Why are t statistics more variable than z-scores?​

Correct AnswerverifiedShow Answer

A sample of n = 16 scores with a sample variance of s2 = 64 would have an estimated standard error of 4 points.

Correct AnswerverifiedShow Answer

If two samples are selected from the same population,under what circumstances are the two samples guaranteed to have exactly the same t statistic?​

Correct AnswerverifiedShow Answer

A researcher conducts a hypothesis test using a sample from an unknown population.If the t statistic has df = 35,how many individuals were in the sample?​

Correct AnswerverifiedShow Answer

A sample of n = 4 scores with SS = 48 has a variance of 16 and an estimated standard error of 2.

Correct AnswerverifiedShow Answer

With α = .05 and df = 8,the critical values for a two-tailed t test are t = ±2.306.Assuming all other factors are held constant,if the df value were increased to df = 20,what would happen to the critical values for t?​

Correct AnswerverifiedShow Answer

A research report states "t(8)= 2.00,p > .05." For this test,r2 = 2/10.

Correct AnswerverifiedFalse

The results of a hypothesis test are reported as follows: t(15) = 2.70,p < .05.Based on this report,how many individuals were in the sample?

Correct Answer
verified

What is the sample variance and the estimated standard error for a sample of n = 9 scores with SS = 72?

Correct Answer
verified

A sample of n = 25 scores has a mean of M = 65 and an estimated standard error of 2 points.What is the sample variance?

Correct Answer
verified

A hypothesis test with a sample of n = 25 participants produces a t statistic of t = +2.53.Assuming a one-tailed test with the critical region in the right-hand tail,what is the correct decision?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

If other factors are held constant,which set of sample characteristics is most likely to reject a null hypothesis stating that m = 80?

Correct Answer
verified

Correct Answer
verified
True

A sample of n = 4 scores is selected from a population with an unknown mean.The sample has a mean of M = 40 and a variance of s² = 16.Which equation correctly describes the 90% confidence interval for μ?

Correct Answer
verified

With α = .05,what is the critical t value for a one-tailed test with n = 15?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
True

Why are t statistics more variable than z-scores?

Correct Answer
verified

A sample of n = 16 scores with a sample variance of s² = 64 would have an estimated standard error of 4 points.

Correct Answer
verified

If two samples are selected from the same population,under what circumstances are the two samples guaranteed to have exactly the same t statistic?

Correct Answer
verified

A researcher conducts a hypothesis test using a sample from an unknown population.If the t statistic has df = 35,how many individuals were in the sample?

Correct Answer
verified

Correct Answer
verified

With α = .05 and df = 8,the critical values for a two-tailed t test are t = ±2.306.Assuming all other factors are held constant,if the df value were increased to df = 20,what would happen to the critical values for t?

Correct Answer
verified

A research report states "t(8)= 2.00,p > .05." For this test,r² = 2/10.

Correct Answer
verified
False