Question 1

According to information supplied by the U.S. Bureau of the Census, between 1955 and 2005, the gender gap in income closed from________.

Accepted Answer

A)  90% to 99% 
B)  40% to 50% 
C)  25% to 28% 
D)  64% to 79% 
A)  90% to 99% 
B)  40% to 50% 
C)  25% to 28% 
D)  64% to 79% D

Question 2

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. B

Question 3

When testing the significance of the difference between two sample proportions, the null hypothesis is________.

Accepted Answer

A)  P s1 = P s2 
B)  P s1 = P s21 
C)  P u = (1 - P u ) 
D)  P u1 = P u2 
A)  P s1 = P s2 
B)  P s1 = P s21 
C)  P u = (1 - P u ) 
D)  P u1 = P u2 D

Question 4

When researchers present their findings using a two-sample hypothesis test, they usually include all but which of the following:________.

Accepted Answer

A)  the sample values. 
B)  the test statistic. 
C)  the degrees of freedom. 
D)  the critical region. 
A)  the sample values. 
B)  the test statistic. 
C)  the degrees of freedom. 
D)  the critical region.

Question 5

The text reports the results of a test for the significance of the difference in average education for random samples of males and females. Both males and females averaged 13.5 years of schooling. The Z score computed in step 4 for this difference was - 0.29. Given these results, which of the following is a reasonable conclusion?

Accepted Answer

A)  The difference is statistically significant, large, and important. 
B)  The difference is not statistically significant and was probably caused by random chance. 
C)  There is an important gender gap in education in the United States. 
D)  This difference is statistically significant but quite small. 
A)  The difference is statistically significant, large, and important. 
B)  The difference is not statistically significant and was probably caused by random chance. 
C)  There is an important gender gap in education in the United States. 
D)  This difference is statistically significant but quite small.

Question 6

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 answer choices 
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 answer choices

Question 7

When testing for the significance of the difference between two sample means, which parameters must be estimated with sample values?

Accepted Answer

A)  The population standard deviations 
B)  The population means 
C)  The standard deviation of the sampling distribution 
D)  The alpha value 
A)  The population standard deviations 
B)  The population means 
C)  The standard deviation of the sampling distribution 
D)  The alpha value

Question 8

Samples of Republicans and Democrats have been tested for their level of support for welfare reform and the null hypothesis has been rejected. What may we conclude?

Accepted Answer

A)  The difference is significant; there are differences between the parties on this issue 
B)  The difference is significant; the parties are the same on this issue 
C)  The difference is not significant 
D)  A Type I error has occurred 
A)  The difference is significant; there are differences between the parties on this issue 
B)  The difference is significant; the parties are the same on this issue 
C)  The difference is not significant 
D)  A Type I error has occurred

Question 9

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 =±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 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

Regarding importance versus statistics:________.

Accepted Answer

A)  there are ways to analyze importance as well as significance. 
B)  researchers cannot formally assess importance. 
C)  there is no difference between importance and significance. 
D)  the distinction is entirely dependent upon data. 
A)  there are ways to analyze importance as well as significance. 
B)  researchers cannot formally assess importance. 
C)  there is no difference between importance and significance. 
D)  the distinction is entirely dependent upon data.

Question 12

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 13

Random samples of men and women have been given a scale that measures their support for gun control. Men average 10.2 with a standard deviation of 5.3. Women also average 10.2 but their standard deviation is 1.8. How could these results be dealt with appropriately?

Accepted Answer

A)  Test the difference in the sample means for statistical significance. 
B)  Since the sample means are the same value, there is no need to conduct any tests; these results cannot be significant. 
C)  A one-tailed test of significance is called for. 
D)  A test of significance with a very high alpha level ( α > 0.10) is called for. 
A)  Test the difference in the sample means for statistical significance. 
B)  Since the sample means are the same value, there is no need to conduct any tests; these results cannot be significant. 
C)  A one-tailed test of significance is called for. 
D)  A test of significance with a very high alpha level ( α > 0.10) is called for.

Question 14

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 15

A pooled estimate________.

Accepted Answer

A)  compares two different populations. 
B)  combines two different populations. 
C)  combines information from two samples. 
D)  is the mean of two standard deviations. 
A)  compares two different populations. 
B)  combines two different populations. 
C)  combines information from two samples. 
D)  is the mean of two standard deviations.

Question 16

To satisfy the requirement of independent random sampling, the researcher________.

Accepted Answer

A)  must use only cluster sampling. 
B)  may randomly select cases from one list of the population, then subdivide that sample according to the trait of interest. 
C)  may randomly select an entire neighborhood, then select any member of each family in that neighborhood. 
D)  must select only very small populations. 
A)  must use only cluster sampling. 
B)  may randomly select cases from one list of the population, then subdivide that sample according to the trait of interest. 
C)  may randomly select an entire neighborhood, then select any member of each family in that neighborhood. 
D)  must select only very small populations.

Question 17

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 answer choices 
A)  theoretically important. 
B)  practically important. 
C)  sociologically important. 
D)  None of the answer choices

Question 18

The text reports the results of a test for the significance of the difference in average income for random samples of males and females. Males earned an average of about $17,000 more per year and the Z score computed in step 4 was 6.28. Given these results, which of the following is a reasonable conclusion?

Accepted Answer

A)  The difference is statistically significant, large, and important. 
B)  The difference is not statistically significant and was probably caused by random chance. 
C)  There is no gender gap in income in the United States. 
D)  This difference is statistically significant but quite small. 
A)  The difference is statistically significant, large, and important. 
B)  The difference is not statistically significant and was probably caused by random chance. 
C)  There is no gender gap in income in the United States. 
D)  This difference is statistically significant but quite small.

Question 19

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

Accepted Answer

A)    
B)  μ > 0 
C)  μ 1 = μ 2 
D)  σ 1 = σ 2 
A)    
B)  μ > 0 
C)  μ 1 = μ 2 
D)  σ 1 = σ 2

Question 20

To maximize the probability of rejecting the null hypothesis, use________.

Accepted Answer

A)  low alphas and two-tailed tests. 
B)  low alphas and high Z scores. 
C)  high alphas but low degrees of freedom. 
D)  high alphas, large samples, and one- tailed tests. 
A)  low alphas and two-tailed tests. 
B)  low alphas and high Z scores. 
C)  high alphas but low degrees of freedom. 
D)  high alphas, large samples, and one- tailed tests.

According to information supplied by the U.S. Bureau of the Census, between 1955 and 2005, the gender gap in income closed from________.

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

When testing the significance of the difference between two sample proportions, the null hypothesis is________.

When researchers present their findings using a two-sample hypothesis test, they usually include all but which of the following:________.

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

When testing for the significance of the difference between two sample means, which parameters must be estimated with sample values?

Samples of Republicans and Democrats have been tested for their level of support for welfare reform and the null hypothesis has been rejected. What may we conclude?

The higher the alpha level,________.

Regarding importance versus statistics:________.

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

Random samples of men and women have been given a scale that measures their support for gun control. Men average 10.2 with a standard deviation of 5.3. Women also average 10.2 but their standard deviation is 1.8. How could these results be dealt with appropriately?

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

A pooled estimate________.

To satisfy the requirement of independent random sampling, the researcher________.

A difference between samples that is shown to be statistically significant is always________.

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

To maximize the probability of rejecting the null hypothesis, use________.

Introduction

Basic Descriptive Statistics Tables Percentages Rates and Ratios and Graphs

Measures of Central Tendency

Measures of Variation

The Normal Curve

Introduction to Inferential Statistics Sampling and the Sampling Distribution

Estimation Procedures

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

Elaborating Bivariate Tables

Partial Correlation and Multiple Regression and Correlation

Filters

Exam 9: Hypothesis Testing Ii the Two Sample Case

According to information supplied by the U.S. Bureau of the Census, between 1955 and 2005, the gender gap in income closed from________.

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

When testing the significance of the difference between two sample proportions, the null hypothesis is________.

When researchers present their findings using a two-sample hypothesis test, they usually include all but which of the following:________.

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

When testing for the significance of the difference between two sample means, which parameters must be estimated with sample values?

Samples of Republicans and Democrats have been tested for their level of support for welfare reform and the null hypothesis has been rejected. What may we conclude?

The higher the alpha level,________.

Regarding importance versus statistics:________.

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

Random samples of men and women have been given a scale that measures their support for gun control. Men average 10.2 with a standard deviation of 5.3. Women also average 10.2 but their standard deviation is 1.8. How could these results be dealt with appropriately?

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

A pooled estimate________.

To satisfy the requirement of independent random sampling, the researcher________.

A difference between samples that is shown to be statistically significant is always________.

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

To maximize the probability of rejecting the null hypothesis, use________.

Introduction

Basic Descriptive Statistics Tables Percentages Rates and Ratios and Graphs

Measures of Central Tendency

Measures of Variation

The Normal Curve

Introduction to Inferential Statistics Sampling and the Sampling Distribution

Estimation Procedures

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

Elaborating Bivariate Tables

Partial Correlation and Multiple Regression and Correlation

Filters