Question 1

For all tests of hypothesis, the probability of rejecting the null hypothesis is a function of

Accepted Answer

A)  the size of the observed differences 
B)  the alpha level and the use of one- or two-tailed tests 
C)  sample size 
D)  all of the above 
A)  the size of the observed differences 
B)  the alpha level and the use of one- or two-tailed tests 
C)  sample size 
D)  all of the above D

Question 2

For testing the difference between two sample means, the level of measurement is assumed to be

Accepted Answer

A)  nominal 
B)  ordinal 
C)  interval-ratio 
D)  any of the above 
A)  nominal 
B)  ordinal 
C)  interval-ratio 
D)  any of the above C

Question 3

For tests of significance involving two sample proportions, the value of the population proportion is estimated from

Accepted Answer

A)  the value of the sample means 
B)  the value of Z (obtained) 
C)  the sample proportions 
D)  the sample standard deviations 
A)  the value of the sample means 
B)  the value of Z (obtained) 
C)  the sample proportions 
D)  the sample standard deviations C

Question 4

According to the text, reading tests conducted on representative samples of American 4th graders show

Accepted Answer

A)  no significant improvement between 2008 and 2012 
B)  a significant decrease in scores since 2008 
C)  a significant increase in scores since 2008 
D)  an increase in average scores for boy since 2008 but not for girls 
A)  no significant improvement between 2008 and 2012 
B)  a significant decrease in scores since 2008 
C)  a significant increase in scores since 2008 
D)  an increase in average scores for boy since 2008 but not for girls

Question 5

When testing for the significance of the difference between two sample means, the null hypothesis can be stated as

Accepted Answer

A)    =
  
B)  $\mu$ > 0 
C)  $\mu$1 = $\mu$2 
D)  $\sigma$1 = $\sigma$2 
A)    =
  
B)  $\mu$ > 0 
C)  $\mu$1 = $\mu$2 
D)  $\sigma$1 = $\sigma$2

Question 6

A researcher conducted a survey to determine if older people have different feelings about abortion than younger people. He used an alpha level of 0.05 (Z critical = $\pm$1.96) to test for significance and found that his computed test statistic was 2.76. Which of the following conclusions is justified?

Accepted Answer

A)  feelings about abortion do not vary by age 
B)  older and younger people have significantly different feelings about abortion 
C)  a one-tailed test should have been used 
D)  a Type II error has occurred 
A)  feelings about abortion do not vary by age 
B)  older and younger people have significantly different feelings about abortion 
C)  a one-tailed test should have been used 
D)  a Type II error has occurred

Question 7

When is the t distribution used instead of the Z distribution to test the significance of the difference between two sample proportions?

Accepted Answer

A)  never 
B)  when sample size is very large 
C)  when one sample is much larger than the other 
D)  when N is small 
A)  never 
B)  when sample size is very large 
C)  when one sample is much larger than the other 
D)  when N is small

Question 8

The central problem in the case of two-sample hypothesis test is to determine

Accepted Answer

A)  if the samples are random 
B)  if sample statistics are the same as those of the sampling distribution 
C)  if the parameters are representative of the populations 
D)  if two populations differ significantly on the trait in question 
A)  if the samples are random 
B)  if sample statistics are the same as those of the sampling distribution 
C)  if the parameters are representative of the populations 
D)  if two populations differ significantly on the trait in question

Question 9

Random samples of 1546 men and 1678 women have been given a scale that measures support of legal abortion. Men average 12.45 and women average 12.46 and the difference is significant at the 0.05 level. What can we conclude?

Accepted Answer

A)  There is an important difference between men and women on this issue. 
B)  Because of the large sample sizes, these results may be statistically significant but trivial. 
C)  The difference should be re-tested with a one-tailed test 
D)  The difference should be re-tested at a higher alpha level 
A)  There is an important difference between men and women on this issue. 
B)  Because of the large sample sizes, these results may be statistically significant but trivial. 
C)  The difference should be re-tested with a one-tailed test 
D)  The difference should be re-tested at a higher alpha level

Question 10

The higher the alpha level,

Accepted Answer

A)  the lower the probability of rejecting the null hypothesis 
B)  the larger the sample size has to be to reject the null hypothesis 
C)  the greater the probability of rejecting the null hypothesis 
D)  the more desirable the two-tailed test 
A)  the lower the probability of rejecting the null hypothesis 
B)  the larger the sample size has to be to reject the null hypothesis 
C)  the greater the probability of rejecting the null hypothesis 
D)  the more desirable the two-tailed test

Question 11

Samples from two high schools are being tested for the difference in their average levels of prejudice. One sample contains 39 respondents and the other sample contains 47 respondents. The appropriate sampling distribution is the

Accepted Answer

A)  t distribution 
B)  Z distribution 
C)  F distribution 
D)  any of the above 
A)  t distribution 
B)  Z distribution 
C)  F distribution 
D)  any of the above

Question 12

From a university population, random samples of 145 men and 237 women have been asked if they have ever cheated in a college class. 8% of the men and 6% of the women said that they have. What is the appropriate test to assess the significance of this difference?

Accepted Answer

A)  test for the significance of the difference between two sample proportions, large samples 
B)  test for the significance of the difference between two sample proportions, small samples 
C)  test for the significance of the difference between two sample proportions, matched samples 
D)  test for the significance of the difference between two sample means, large samples 
A)  test for the significance of the difference between two sample proportions, large samples 
B)  test for the significance of the difference between two sample proportions, small samples 
C)  test for the significance of the difference between two sample proportions, matched samples 
D)  test for the significance of the difference between two sample means, large samples

Question 13

A difference between samples that is shown to be statistically significant is always

Accepted Answer

A)  theoretically important 
B)  practically important 
C)  sociologically important 
D)  none of the above 
A)  theoretically important 
B)  practically important 
C)  sociologically important 
D)  none of the above

Question 14

Rejection of the null hypothesis in the two-sample case implies that the

Accepted Answer

A)  samples are different on the trait of interest 
B)  populations from which the samples are drawn are different on the trait of interest 
C)  samples are not different on the trait of interest 
D)  populations from which the samples are drawn are not different on the trait of interest 
A)  samples are different on the trait of interest 
B)  populations from which the samples are drawn are different on the trait of interest 
C)  samples are not different on the trait of interest 
D)  populations from which the samples are drawn are not different on the trait of interest

Question 15

When testing for the significance of the difference between two sample means, we must first estimate ___________ before we can compute the test statistic.

Accepted Answer

A)  the standard deviation of the sampling distribution 
B)  the standard deviations of the samples 
C)  the population means 
D)  the critical region 
A)  the standard deviation of the sampling distribution 
B)  the standard deviations of the samples 
C)  the population means 
D)  the critical region

Question 16

In the two sample case, the null hypothesis is always about the difference in the

Accepted Answer

A)  populations 
B)  samples 
C)  standard errors 
D)  all of the above 
A)  populations 
B)  samples 
C)  standard errors 
D)  all of the above

Question 17

The lower the alpha level,

Accepted Answer

A)  the lower the probability of rejecting the null hypothesis 
B)  the larger the sample size has to be to reject the null hypothesis 
C)  the greater the probability of rejecting the null hypothesis 
D)  the more desirable the two-tailed test 
A)  the lower the probability of rejecting the null hypothesis 
B)  the larger the sample size has to be to reject the null hypothesis 
C)  the greater the probability of rejecting the null hypothesis 
D)  the more desirable the two-tailed test

Question 18

When testing for the significance of the difference between sample means with small samples, the proper sampling distribution is

Accepted Answer

A)  the alpha distribution 
B)  the beta distribution 
C)  the Z distribution 
D)  the t distribution 
A)  the alpha distribution 
B)  the beta distribution 
C)  the Z distribution 
D)  the t distribution

Question 19

According to the text, which of the following is true regarding the gender gap in average income?

Accepted Answer

A)  the gap has grown wider every year since the 1950s 
B)  the gap has grown smaller every year since the 1950s 
C)  the gap shrank to about 79% in 2012 
D)  the gap shrank to about 98% in 2012: a gender gap in income no longer exists 
A)  the gap has grown wider every year since the 1950s 
B)  the gap has grown smaller every year since the 1950s 
C)  the gap shrank to about 79% in 2012 
D)  the gap shrank to about 98% in 2012: a gender gap in income no longer exists

Question 20

The value of all test statistics increases as _______ increases

Accepted Answer

A)  the sampling distribution 
B)  the alpha level 
C)  the size of the critical region 
D)  sample size 
A)  the sampling distribution 
B)  the alpha level 
C)  the size of the critical region 
D)  sample size

For all tests of hypothesis, the probability of rejecting the null hypothesis is a function of

For testing the difference between two sample means, the level of measurement is assumed to be

For tests of significance involving two sample proportions, the value of the population proportion is estimated from

According to the text, reading tests conducted on representative samples of American 4th graders show

When testing for the significance of the difference between two sample means, the null hypothesis can be stated as

When is the t distribution used instead of the Z distribution to test the significance of the difference between two sample proportions?

The central problem in the case of two-sample hypothesis test is to determine

Random samples of 1546 men and 1678 women have been given a scale that measures support of legal abortion. Men average 12.45 and women average 12.46 and the difference is significant at the 0.05 level. What can we conclude?

The higher the alpha level,

Samples from two high schools are being tested for the difference in their average levels of prejudice. One sample contains 39 respondents and the other sample contains 47 respondents. The appropriate sampling distribution is the

From a university population, random samples of 145 men and 237 women have been asked if they have ever cheated in a college class. 8% of the men and 6% of the women said that they have. What is the appropriate test to assess the significance of this difference?

A difference between samples that is shown to be statistically significant is always

Rejection of the null hypothesis in the two-sample case implies that the

When testing for the significance of the difference between two sample means, we must first estimate ___________ before we can compute the test statistic.

In the two sample case, the null hypothesis is always about the difference in the

The lower the alpha level,

When testing for the significance of the difference between sample means with small samples, the proper sampling distribution is

According to the text, which of the following is true regarding the gender gap in average income?

The value of all test statistics increases as _______ increases

Introduction

Basic Descriptive Statistics Percentages, Ratios Rates, Tables, Charts Graphs

Measures of Central Tendency

Measures of Dispersion

The Normal Curve

Introduction to Inferential Statistics Sampling the Sampling Distribution

Hypothesis Testing I the One-Sample Case

Hypothesis Testing III: the Analysis of Variance

Hypothesis Testing Iv Chi Square

Bivariate Association for Nominal- and Ordinal-Level Variables

Association Between Variables Measured at the Interval-Ratio Level

Partial Correlation and

Filters

Exam 8: Hypothesis Testing II the Two-Sample Case

For all tests of hypothesis, the probability of rejecting the null hypothesis is a function of

For testing the difference between two sample means, the level of measurement is assumed to be

For tests of significance involving two sample proportions, the value of the population proportion is estimated from

According to the text, reading tests conducted on representative samples of American 4th graders show

When testing for the significance of the difference between two sample means, the null hypothesis can be stated as

When is the t distribution used instead of the Z distribution to test the significance of the difference between two sample proportions?

The central problem in the case of two-sample hypothesis test is to determine

Random samples of 1546 men and 1678 women have been given a scale that measures support of legal abortion. Men average 12.45 and women average 12.46 and the difference is significant at the 0.05 level. What can we conclude?

The higher the alpha level,

Samples from two high schools are being tested for the difference in their average levels of prejudice. One sample contains 39 respondents and the other sample contains 47 respondents. The appropriate sampling distribution is the

From a university population, random samples of 145 men and 237 women have been asked if they have ever cheated in a college class. 8% of the men and 6% of the women said that they have. What is the appropriate test to assess the significance of this difference?

A difference between samples that is shown to be statistically significant is always

Rejection of the null hypothesis in the two-sample case implies that the

When testing for the significance of the difference between two sample means, we must first estimate ___________ before we can compute the test statistic.

In the two sample case, the null hypothesis is always about the difference in the

The lower the alpha level,

When testing for the significance of the difference between sample means with small samples, the proper sampling distribution is

According to the text, which of the following is true regarding the gender gap in average income?

The value of all test statistics increases as _______ increases

Introduction

Basic Descriptive Statistics Percentages, Ratios Rates, Tables, Charts Graphs

Measures of Central Tendency

Measures of Dispersion

The Normal Curve

Introduction to Inferential Statistics Sampling the Sampling Distribution

Hypothesis Testing I the One-Sample Case

Hypothesis Testing III: the Analysis of Variance

Hypothesis Testing Iv Chi Square

Bivariate Association for Nominal- and Ordinal-Level Variables

Association Between Variables Measured at the Interval-Ratio Level

Partial Correlation and

Filters