Question 1

Two researchers measure attitudes toward capital punishment in the year 2000 and again in the year 2005. One researcher uses a panel study design (the same persons are questioned in 2000 and in 2005); the other uses a trend study design (different samples from the population are questioned in 2000 and 2005). In analyzing the data that was collected,

Accepted Answer

The panel study researcher should use paired-sample t tests because they are collecting data from the same individuals at two different time points. Paired-sample t tests are used to analyze the differences between two measurements taken from the same group of individuals. On the other hand, the trend study researcher should use independent-samples t tests because they are collecting data from different individuals at two different time points. Independent-samples t tests are used to compare the means of two different groups of individuals.

Question 2

You are testing a two-tailed hypothesis. Your SPSS output tells you that the two-tailed significance level of a particular t statistic is .01. What is the probability of making a Type I error if you reject the null hypothesis?

Accepted Answer

The probability of making a Type I error (rejecting a true null hypothesis) is equal to the significance level (p-value), which is .01 in this case.

Question 3

Which would be an appropriate statistical procedure to test the hypothesis that Americans listen to radio an average of 200 minutes a day?

Accepted Answer

A one-sample t test is appropriate for testing the hypothesis that a sample mean is equal to a specified population mean. In this case, the hypothesis is that the population mean for radio listening is 200 minutes a day, and the one-sample t test would be used to determine if a sample mean is significantly different from this value.

Question 4

You are doing a paired-samples t test with 694 valid cases. How many degrees of freedom will the t test have?

Accepted Answer

The degrees of freedom for a paired-samples t-test is calculated as the number of pairs minus one, so with 694 valid cases (pairs), it would be 694 - 1 = 693.

Question 5

Without computing any new variables, which would be an appropriate statistical procedure to test the hypothesis that, on average, college students listen to less radio than they did when they were high school students?

Accepted Answer

A paired-samples t test is appropriate because it compares the means of two related groups to determine if there is a statistically significant difference between these means. In this case, the same individuals are being compared at two different times (as college students versus as high school students), making their responses paired.

Question 6

You are doing a paired-samples t test. What level of measurement is required on the variables you are using?

Accepted Answer

A paired-samples t test requires interval/ratio level of measurement on the variables being used. This is because the test relies on calculating the mean difference between paired observations and the standard deviation of these differences, which can only be calculated using interval/ratio data. Nominal and ordinal data do not have a meaningful numerical value that can be used in these calculations.

Question 7

What is the largest risk of making a Type I error that social scientists will usually take?

Accepted Answer

Social scientists typically use a significance level of 0.05 (5%) to determine whether to reject the null hypothesis and accept the alternative hypothesis. This means that there is a 5% chance of making a Type I error, which is the largest risk that they typically take.

Question 8

An author reports the following information about a two-tailed paired-samples t test: t = 5.43, df = 83, p = .001. Which of the following is true?

Accepted Answer

The p-value is less than .05 (the typical alpha level), so the null hypothesis (that the two means are equal) is rejected. Therefore, choice B is correct. Choices A and C cannot both be true because if the null hypothesis is rejected, then the two means are significantly different, so only one of those options can be true. Therefore, choice D is incorrect.

Question 9

Which of the following correctly describes a Type I error?

Accepted Answer

A Type I error occurs when we reject a null hypothesis that is actually true. This means we mistakenly assume there is an effect or relationship when there really isn't one.

Question 10

Which of the following hypotheses should be tested using a paired-samples t test?

Accepted Answer

A paired-samples t test is appropriate when comparing the means of two related samples (pretest and posttest scores in this case), and the hypothesis that their means are equal is being tested. Option A does not involve a comparison with a related sample, option B involves comparing two groups (men and women), and option D involves testing a correlation rather than a mean difference.

Question 11

For an independent-samples t test, the test variable (the variable whose values will be averaged for each group) can be what level of measurement?

Accepted Answer

An independent-samples t test is used to compare the means of two independent groups, so the test variable (the variable whose values will be averaged for each group) should be measured at the interval/ratio level to allow for meaningful averaging and statistical comparison. If the variable is measured at the nominal or ordinal level, the values cannot be averaged in a meaningful way and the test would not be appropriate.

Question 12

Any paired-samples t test could also be tested as a(n)

Accepted Answer

A paired-samples t test compares the means of two related groups to determine if there is a statistically significant difference between these means. This can be conceptualized as comparing the mean difference to zero, which aligns with the logic of a one-sample t test where the mean of a single sample is compared to a known value or theoretical expectation (in this case, the difference expected is zero if there's no change or effect). The other options do not directly align with the conceptual framework of a paired-samples t test.

Question 13

Your independent-samples t test research hypothesis is that, when asked the ideal number of children to have, men report a higher average than women. The following results are consistent with the _____ and you proceed to _____.

Accepted Answer

The results are consistent with the research hypothesis if men report a higher average number of children than women, which means you proceed to Step 3 to check the significance level of your findings before drawing a conclusion.

Question 14

You are doing a two-tailed paired-samples t test and your results are statistically significant. The phrase "statistical significance" means the same as which of the following?

Accepted Answer

Statistical significance means that the results are unlikely to occur by chance and are instead due to a true difference between the means. In the case of a two-tailed paired-samples t test, a statistically significant result means that we are willing to reject the null hypothesis that there is no difference between the means in the population. Therefore, choice C is the best answer. Choices A and B are incorrect because statistical significance does not necessarily imply a large or important difference. Choice D is also incorrect because a statistically significant result means that we are rejecting the claim of no difference.

Question 15

Which of the following hypotheses should be tested using an independent-samples t test?

Accepted Answer

An independent-samples t test is used to compare the means of two different groups. As such, hypothesis B, examining whether there is a difference in pretest score means between men and women, is the most appropriate for the test. Hypothesis A is a statement about a single group's posttest scores, not a comparison between groups. Hypothesis C is comparing individuals' pre and posttest scores, not comparing the means of different groups. Hypothesis D is examining correlation, not differences between means.

Question 16

An author reports the following information about a one-tailed independent-samples t test: t = 1.71, df = 17, p = .111. The sample means were consistent with the research hypothesis. Which of the following is true?

Accepted Answer

Given the one-tailed p-value is .111, the two-tailed p-value would be double that (assuming a symmetric distribution), hence .222, making option A correct. The null hypothesis is not rejected at common significance levels (e.g., .05) given p = .111, and thus, we cannot conclude the groups were significantly different, making B and C incorrect.

Question 17

For an independent-samples t test, the grouping variable (the variable whose attributes are used to identify the two groups to be compared) can be what level of measurement?

Accepted Answer

The independent-samples t test can be used to compare two groups identified by a grouping variable that can be either interval/ratio, ordinal, or nominal. Therefore, all three options are valid choices for the level of measurement of the grouping variable.

Question 18

Your paired-samples t test research hypothesis is that, on average, persons wish they had fewer children (KIDSBEST) than they actually have (CHILDREN). The following results are consistent with the _____ and you proceed to _____.

Accepted Answer

The answer of Your paired-samples t test research hypothesis is...

Question 19

If the significance level of Levene's Test is.050 or less,

Accepted Answer

If the significance level of Levene's Test is .050 or less, it indicates that the variances are not equal, so you should use the lower line of results (Equal variances not assumed) in the t-test output.

Question 20

You are testing a one-tailed paired-samples t test hypothesis. The sample means were consistent with the research hypothesis. Based on the following results, the significance level is _____ and you _____ the null hypothesis.

Accepted Answer

The significance level is not provided directly, but the decision to "do not reject" the null hypothesis implies that the p-value is higher than the common alpha level of 0.05, making choice A (.056) the correct answer as it is the only option slightly above 0.05 and indicates not rejecting the null hypothesis.

Quiz 13: Paired and Independent-Samples T Tests

You are testing a two-tailed hypothesis. Your SPSS output tells you that the two-tailed significance level of a particular t statistic is .01. What is the probability of making a Type I error if you reject the null hypothesis?

Which would be an appropriate statistical procedure to test the hypothesis that Americans listen to radio an average of 200 minutes a day?

You are doing a paired-samples t test with 694 valid cases. How many degrees of freedom will the t test have?

Without computing any new variables, which would be an appropriate statistical procedure to test the hypothesis that, on average, college students listen to less radio than they did when they were high school students?

You are doing a paired-samples t test. What level of measurement is required on the variables you are using?

What is the largest risk of making a Type I error that social scientists will usually take?

An author reports the following information about a two-tailed paired-samples t test: t = 5.43, df = 83, p = .001. Which of the following is true?

Which of the following correctly describes a Type I error?

Which of the following hypotheses should be tested using a paired-samples t test?

For an independent-samples t test, the test variable (the variable whose values will be averaged for each group) can be what level of measurement?

Any paired-samples t test could also be tested as a(n)

Your independent-samples t test research hypothesis is that, when asked the ideal number of children to have, men report a higher average than women. The following results are consistent with the _ and you proceed to _.

You are doing a two-tailed paired-samples t test and your results are statistically significant. The phrase "statistical significance" means the same as which of the following?

Which of the following hypotheses should be tested using an independent-samples t test?

An author reports the following information about a one-tailed independent-samples t test: t = 1.71, df = 17, p = .111. The sample means were consistent with the research hypothesis. Which of the following is true?

For an independent-samples t test, the grouping variable (the variable whose attributes are used to identify the two groups to be compared) can be what level of measurement?

Your paired-samples t test research hypothesis is that, on average, persons wish they had fewer children (KIDSBEST) than they actually have (CHILDREN) . The following results are consistent with the _ and you proceed to _.

If the significance level of Levene's Test is.050 or less,

You are testing a one-tailed paired-samples t test hypothesis. The sample means were consistent with the research hypothesis. Based on the following results, the significance level is _ and you _ the null hypothesis.

Quiz 13: Paired and Independent-Samples T Tests

You are testing a two-tailed hypothesis. Your SPSS output tells you that the two-tailed significance level of a particular t statistic is .01. What is the probability of making a Type I error if you reject the null hypothesis?

Which would be an appropriate statistical procedure to test the hypothesis that Americans listen to radio an average of 200 minutes a day?

You are doing a paired-samples t test with 694 valid cases. How many degrees of freedom will the t test have?

Without computing any new variables, which would be an appropriate statistical procedure to test the hypothesis that, on average, college students listen to less radio than they did when they were high school students?

You are doing a paired-samples t test. What level of measurement is required on the variables you are using?

What is the largest risk of making a Type I error that social scientists will usually take?

An author reports the following information about a two-tailed paired-samples t test: t = 5.43, df = 83, p = .001. Which of the following is true?

Which of the following correctly describes a Type I error?

Which of the following hypotheses should be tested using a paired-samples t test?

For an independent-samples t test, the test variable (the variable whose values will be averaged for each group) can be what level of measurement?

Any paired-samples t test could also be tested as a(n)

Your independent-samples t test research hypothesis is that, when asked the ideal number of children to have, men report a higher average than women. The following results are consistent with the _____ and you proceed to _____.

You are doing a two-tailed paired-samples t test and your results are statistically significant. The phrase "statistical significance" means the same as which of the following?

Which of the following hypotheses should be tested using an independent-samples t test?

An author reports the following information about a one-tailed independent-samples t test: t = 1.71, df = 17, p = .111. The sample means were consistent with the research hypothesis. Which of the following is true?

For an independent-samples t test, the grouping variable (the variable whose attributes are used to identify the two groups to be compared) can be what level of measurement?

Your paired-samples t test research hypothesis is that, on average, persons wish they had fewer children (KIDSBEST) than they actually have (CHILDREN) . The following results are consistent with the _____ and you proceed to _____.

If the significance level of Levene's Test is.050 or less,

You are testing a one-tailed paired-samples t test hypothesis. The sample means were consistent with the research hypothesis. Based on the following results, the significance level is _____ and you _____ the null hypothesis.

Your independent-samples t test research hypothesis is that, when asked the ideal number of children to have, men report a higher average than women. The following results are consistent with the _ and you proceed to _.

Your paired-samples t test research hypothesis is that, on average, persons wish they had fewer children (KIDSBEST) than they actually have (CHILDREN) . The following results are consistent with the _ and you proceed to _.

You are testing a one-tailed paired-samples t test hypothesis. The sample means were consistent with the research hypothesis. Based on the following results, the significance level is _ and you _ the null hypothesis.