Question 1

A one-tailed statistical test is used when:

Accepted Answer

A) the data are from a ratio scale. 
B) the data are from an ordinal scale. 
C) there is a specific prediction regarding the direction of difference between groups. 
D) there is no prediction regarding the direction of difference between groups. 
A) the data are from a ratio scale. 
B) the data are from an ordinal scale. 
C) there is a specific prediction regarding the direction of difference between groups. 
D) there is no prediction regarding the direction of difference between groups.

Question 2

The _____ is commonly used to examine whether two groups are significantly different from each other.

Accepted Answer

A) t test 
B) Mann-Whitney U test 
C) Chi-square test 
D) r test 
A) t test 
B) Mann-Whitney U test 
C) Chi-square test 
D) r test

Question 3

Rejecting the null hypothesis when it is true is called a _____ error, whereas not rejecting a false null hypothesis when it is false is called a(n) _____ error.

Accepted Answer

A) beta; alpha 
B) Type I; Type II 
C) minor; major 
D) significant; insignificant 
A) beta; alpha 
B) Type I; Type II 
C) minor; major 
D) significant; insignificant

Question 4

Arafa has collected data on the relationship between physical attractiveness and judgments of personality characteristics. In order to determine if the results obtained from the sample are representative of the population, Arafa will need to employ _____ statistics.

Accepted Answer

A) qualitative 
B) descriptive 
C) inferential 
D) ordinal 
A) qualitative 
B) descriptive 
C) inferential 
D) ordinal

Question 5

According to a survey, 57 percent of the citizens of the United States prefer a Democratic candidate, while 43 percent of the citizens prefer a Republican candidate in an election. The survey reports a confidence interval (CFI) of 95 percent + or -3. What can be concluded from these results?

Accepted Answer

A) The Republican candidate will win the election. 
B) There is a 95 percent chance of making a correct prediction about the election. 
C) There is a 5 percent chance of making a correct prediction about the election. 
D) There is no way of knowing which candidate has a higher likelihood of being elected. 
A) The Republican candidate will win the election. 
B) There is a 95 percent chance of making a correct prediction about the election. 
C) There is a 5 percent chance of making a correct prediction about the election. 
D) There is no way of knowing which candidate has a higher likelihood of being elected.

Question 6

A consumer analyst asks participants to rate the comfort of the ride for two brands of all-terrain tires-Trail Cushion and Mud Handler. Trail Cushion is rated more comfortable with a mean of 5.5 than Mud Handler, which is found to have a mean of 4.3. The Type I error would be to conclude that Trail Cushion is:

Accepted Answer

A) more comfortable than Mud Handler when a true difference in comfort exists. 
B) no more comfortable than Mud Handler when Trail Cushion is actually more comfortable. 
C) no more comfortable than Mud Handler when no difference in comfort exists. 
D) more comfortable than Mud Handler when the two tires are equally comfortable. 
A) more comfortable than Mud Handler when a true difference in comfort exists. 
B) no more comfortable than Mud Handler when Trail Cushion is actually more comfortable. 
C) no more comfortable than Mud Handler when no difference in comfort exists. 
D) more comfortable than Mud Handler when the two tires are equally comfortable.

Question 7

A Type II error occurs when one:

Accepted Answer

A) rejects the null hypothesis when it is false. 
B) rejects the null hypothesis when it is true. 
C) accepts the null hypothesis when it is true. 
D) accepts the null hypothesis when it is false. 
A) rejects the null hypothesis when it is false. 
B) rejects the null hypothesis when it is true. 
C) accepts the null hypothesis when it is true. 
D) accepts the null hypothesis when it is false.

Question 8

The research hypothesis states that the:

Accepted Answer

A) independent variable has no effect. 
B) independent variable has an effect. 
C) dependent variable has no effect. 
D) dependent variable has an effect. 
A) independent variable has no effect. 
B) independent variable has an effect. 
C) dependent variable has no effect. 
D) dependent variable has an effect.

Question 9

Statistically, significant results mean that the results are:

Accepted Answer

A) very important. 
B) meaningless. 
C) likely to be due to chance differences between the groups. 
D) likely to be due to true differences between the groups. 
A) very important. 
B) meaningless. 
C) likely to be due to chance differences between the groups. 
D) likely to be due to true differences between the groups.

Question 10

Sean wants to test a hypothesis according to which the mean amount of sales dollars will vary between Oak Ridge, Oak Wood, and Oak Park shopping malls. The appropriate statistical test would be the _____.

Accepted Answer

A) Mann-Whitney U 
B) t-test 
C) F-test 
D) Pearson r 
A) Mann-Whitney U 
B) t-test 
C) F-test 
D) Pearson r

Question 11

Which of the following statements is true of a null hypothesis?

Accepted Answer

A) The population means are not equal. 
B) The difference in means is not due to random error. 
C) The mean of the experimental group is not equal to the mean of the control group. 
D) The mean of the placebo treatment is equal to the mean of the experimental treatment group. 
A) The population means are not equal. 
B) The difference in means is not due to random error. 
C) The mean of the experimental group is not equal to the mean of the control group. 
D) The mean of the placebo treatment is equal to the mean of the experimental treatment group.

Question 12

Reida has developed a program that is designed to increase the reading comprehension scores of sixth graders. She randomly selects three students to participate in her program. When she compares the mean score of the students who completed her program to that of three students who did not participate in the program, she finds no significant difference between the mean scores. What is most likely the reason for the nonsignificant finding?

Accepted Answer

A) Too strong a manipulation 
B) The participation of sixth graders 
C) A small sample size 
D) A true research hypothesis 
A) Too strong a manipulation 
B) The participation of sixth graders 
C) A small sample size 
D) A true research hypothesis

Question 13

A _____ result is one that has a very low probability of occurring if the population means are equal.

Accepted Answer

A) simplistic 
B) significant 
C) specifiable 
D) systematic 
A) simplistic 
B) significant 
C) specifiable 
D) systematic

Question 14

According to her statistical analysis, an investigator found that significantly more men than women used punishment to discipline their children. Thus, the investigator would:

Accepted Answer

A) accept the null hypothesis. 
B) reject the null hypothesis. 
C) make a Type II error. 
D) make a Type I error. 
A) accept the null hypothesis. 
B) reject the null hypothesis. 
C) make a Type II error. 
D) make a Type I error.

Question 15

A researcher wants to test a hypothesis according to which the mean rating of guilt will be higher for unattractive defendants than for attractive defendants. The appropriate statistical test would be the _____.

Accepted Answer

A) Pearson r 
B) two-tailed t-test 
C) one-tailed t-test 
D) chi-square 
A) Pearson r 
B) two-tailed t-test 
C) one-tailed t-test 
D) chi-square

Question 16

Andrea is told that the means of two groups in a study were statistically significant. She knows the means and standard deviations of the two groups and is interested in calculating an estimate of effect size. Given this information, which effect size estimate should she calculate?

Accepted Answer

A) F 
B) Effect size r 
C) Cohen's d 
D) Alpha 
A) F 
B) Effect size r 
C) Cohen's d 
D) Alpha

Question 17

A researcher assesses the length of the prison sentence for physically attractive and physically unattractive defendants. He believes that attractive defendants will receive shorter prison sentences than unattractive defendants. The null hypothesis would suggest that:

Accepted Answer

A) there is no difference in the length of the prison sentence received by attractive and unattractive defendants. 
B) physically attractive defendants will receive longer prison sentences than physically unattractive defendants. 
C) physically attractive defendants will receive shorter prison sentences than physically unattractive defendants. 
D) some other variable such as gender is responsible for the difference in the length of prison sentence. 
A) there is no difference in the length of the prison sentence received by attractive and unattractive defendants. 
B) physically attractive defendants will receive longer prison sentences than physically unattractive defendants. 
C) physically attractive defendants will receive shorter prison sentences than physically unattractive defendants. 
D) some other variable such as gender is responsible for the difference in the length of prison sentence.

Question 18

A researcher employs inferential statistics to examine the difference in mean scores obtained by fourth grade boys and girls in a standardized math test. In this case, inferential statistics:

Accepted Answer

A) summarize and describe the important characteristics of the data. 
B) test the research hypothesis. 
C) indicate the strength of the relationship between the math scores of boys and girls. 
D) indicate the probability that the difference between means reflect random error. 
A) summarize and describe the important characteristics of the data. 
B) test the research hypothesis. 
C) indicate the strength of the relationship between the math scores of boys and girls. 
D) indicate the probability that the difference between means reflect random error.

Question 19

Which significance level would minimize the probability of a Type I error?

Accepted Answer

A) .25 
B) .10 
C) .05 
D) .01 
A) .25 
B) .10 
C) .05 
D) .01

Question 20

Which statistical test would be most appropriate for examining the relationship between temperature and the number of ice cream cones sold?

Accepted Answer

A) Chi-square test 
B) Analysis of variance 
C) t test 
D) Pearson correlation 
A) Chi-square test 
B) Analysis of variance 
C) t test 
D) Pearson correlation

A one-tailed statistical test is used when:

The _____ is commonly used to examine whether two groups are significantly different from each other.

Rejecting the null hypothesis when it is true is called a _ error, whereas not rejecting a false null hypothesis when it is false is called a(n) _ error.

Arafa has collected data on the relationship between physical attractiveness and judgments of personality characteristics. In order to determine if the results obtained from the sample are representative of the population, Arafa will need to employ _____ statistics.

According to a survey, 57 percent of the citizens of the United States prefer a Democratic candidate, while 43 percent of the citizens prefer a Republican candidate in an election. The survey reports a confidence interval (CFI) of 95 percent + or -3. What can be concluded from these results?

A Type II error occurs when one:

The research hypothesis states that the:

Statistically, significant results mean that the results are:

Sean wants to test a hypothesis according to which the mean amount of sales dollars will vary between Oak Ridge, Oak Wood, and Oak Park shopping malls. The appropriate statistical test would be the _____.

Which of the following statements is true of a null hypothesis?

A _____ result is one that has a very low probability of occurring if the population means are equal.

According to her statistical analysis, an investigator found that significantly more men than women used punishment to discipline their children. Thus, the investigator would:

A researcher wants to test a hypothesis according to which the mean rating of guilt will be higher for unattractive defendants than for attractive defendants. The appropriate statistical test would be the _____.

Andrea is told that the means of two groups in a study were statistically significant. She knows the means and standard deviations of the two groups and is interested in calculating an estimate of effect size. Given this information, which effect size estimate should she calculate?

A researcher assesses the length of the prison sentence for physically attractive and physically unattractive defendants. He believes that attractive defendants will receive shorter prison sentences than unattractive defendants. The null hypothesis would suggest that:

A researcher employs inferential statistics to examine the difference in mean scores obtained by fourth grade boys and girls in a standardized math test. In this case, inferential statistics:

Which significance level would minimize the probability of a Type I error?

Which statistical test would be most appropriate for examining the relationship between temperature and the number of ice cream cones sold?

Scientific Understanding of Behavior

Where to Start

Ethics in Behavioral Research

Fundamental Research Issues

Measurement Concepts

Observational Methods

Asking People About Themselves: Survey Research

Experimental Design

Conducting Experiments

Complex Experimental Designs

Single-Case, Quasi-Experimental, and Developmental Research

Understanding Research Results: Description and Correlation

Generalization

Filters

Exam 13: Understanding Research Results: Statistical Inference

A one-tailed statistical test is used when:

The _____ is commonly used to examine whether two groups are significantly different from each other.

Rejecting the null hypothesis when it is true is called a _____ error, whereas not rejecting a false null hypothesis when it is false is called a(n) _____ error.

Arafa has collected data on the relationship between physical attractiveness and judgments of personality characteristics. In order to determine if the results obtained from the sample are representative of the population, Arafa will need to employ _____ statistics.

According to a survey, 57 percent of the citizens of the United States prefer a Democratic candidate, while 43 percent of the citizens prefer a Republican candidate in an election. The survey reports a confidence interval (CFI) of 95 percent + or -3. What can be concluded from these results?

A Type II error occurs when one:

The research hypothesis states that the:

Statistically, significant results mean that the results are:

Sean wants to test a hypothesis according to which the mean amount of sales dollars will vary between Oak Ridge, Oak Wood, and Oak Park shopping malls. The appropriate statistical test would be the _____.

Which of the following statements is true of a null hypothesis?

A _____ result is one that has a very low probability of occurring if the population means are equal.

According to her statistical analysis, an investigator found that significantly more men than women used punishment to discipline their children. Thus, the investigator would:

A researcher wants to test a hypothesis according to which the mean rating of guilt will be higher for unattractive defendants than for attractive defendants. The appropriate statistical test would be the _____.

Andrea is told that the means of two groups in a study were statistically significant. She knows the means and standard deviations of the two groups and is interested in calculating an estimate of effect size. Given this information, which effect size estimate should she calculate?

A researcher assesses the length of the prison sentence for physically attractive and physically unattractive defendants. He believes that attractive defendants will receive shorter prison sentences than unattractive defendants. The null hypothesis would suggest that:

A researcher employs inferential statistics to examine the difference in mean scores obtained by fourth grade boys and girls in a standardized math test. In this case, inferential statistics:

Which significance level would minimize the probability of a Type I error?

Which statistical test would be most appropriate for examining the relationship between temperature and the number of ice cream cones sold?

Scientific Understanding of Behavior

Where to Start

Ethics in Behavioral Research

Fundamental Research Issues

Measurement Concepts

Observational Methods

Asking People About Themselves: Survey Research

Experimental Design

Conducting Experiments

Complex Experimental Designs

Single-Case, Quasi-Experimental, and Developmental Research

Understanding Research Results: Description and Correlation

Generalization

Filters

Rejecting the null hypothesis when it is true is called a _ error, whereas not rejecting a false null hypothesis when it is false is called a(n) _ error.