Deck 13: Understanding Research Results: Statistical-Inference Basics

Question 1

The research hypothesis states that the

A) independent variable had no effect.
B) independent variable did have an effect.
C) dependent variable had no effect.
D) dependent variable did have an effect.

Answer 1

B

Question 2

When a researcher _____ the probability of making a Type I error,she _____ the probability of making a Type II error.

A) increases;increases
B) decreases;increases
C) decreases;decreases
D) decreases;does not affect

Answer 2

B

Question 3

Negative results are problematical because they

A) are difficult to interpret.
B) are less important.
C) disprove the theory you are trying to support.
D) are difficult to analyze statistically.

Answer 3

A

Question 4

Sandra has developed a program designed to increase reading comprehension scores in 6^th graders.She randomly selects three students and has them participate in her program.When she compares the mean score from the students who completed her program to three students who did not participate in the program,she finds no significant difference between their mean scores.What is most likely the reason for the non-significant finding?

A) Too strong of a manipulation
B) The use of 6^th grade children
C) A small sample size
D) A true research hypothesis

Question 5

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

A) Pearson r.
B) 2-tailed t-test.
C) 1 tailed t-test.
D) chi-square.

Question 6

In a multiple-choice question with four alternatives,if the null hypothesis is correct,the probability of a person choosing the correct answer is approximately

A) 1 out of 4.
B) 2 out of 4.
C) 3 out of 4.
D) 4 out of 4.

Question 7

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

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

Question 8

The appropriate statistical test for interval or ratio level data derived from measuring the dependent variable (for more than two groups)is the

A) t-test.
B) Pearson correlation.
C) chi-square.
D) F test (analysis of variance).

Question 9

How do you calculate the systematic variance?

A) Find the deviation of the individual scores from the group mean.
B) Find the deviation of the group means from the grand mean.
C) Find the deviation of error variance from the group mean.
D) Find the deviation of error variance from the grand mean.

Question 10

The null hypothesis

A) is used because it is a very precise statement.
B) is rejected when there is a high probability that the obtained results are due to random error.
C) does not allow us to know the probability of the outcome of the study occurring.
D) is statistically significant if it can be accepted.

Question 11

The desired probability of correctly rejecting the null hypothesis is the

A) Type I error.
B) Type II error.
C) effect size of the test.
D) power of the test.

Question 12

Error variance is the deviation of

A) the individual scores about the group mean.
B) the group means about the grand mean.
C) error variance about the group mean.
D) error variance about the grand mean

Question 13

Brandon found no significant difference in amount of money spent on entertainment between students who live on versus off campus.Based on this finding,Brandon would

A) fail to reject the null.
B) reject the null.
C) accept a Type I error.
D) reject a Type I error.

Question 14

Juan wants to test the hypothesis that 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

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

Question 15

_____ is a type of correlation coefficient that indicates the _____ the effect of the independent variable.

A) T ;difference in
B) T ;magnitude of
C) Effect size r;difference in
D) Effect size r;magnitude of

Question 16

A student is interested in the effect of environmental condition on task performance.She has participants complete a series of math problems under different temperatures (cold,warm,hot)and noise condition (quiet,noisy).The most appropriate test to analyze the data would be a(n)

A) t-test.
B) Pearson r.
C) chi-square.
D) F-test.

Question 17

The expected value of t if the null hypothesis is true would

A) equal 1.
B) equal 0.
C) depend on the degrees of freedom.
D) vary depending on the alpha level.

Question 18

Which one of the following accurately describes the relationship between concepts?

A) Systematic variance = error variance
B) Error variance = between-groups variance
C) Between-groups variance = systematic variance
D) Systematic variance = within-group variance

Question 19

The appropriate statistical test for nominal level data derived from measuring the dependent variable (for two groups)is

A) t.
B) Pearson correlation.
C) chi-square.
D) analysis of variance.

Question 20

Your lab group must choose a significance test to determine if the mean scores of two groups are significantly different.The appropriate test is a(n)

A) t test.
B) Mann-Whitney U.
C) chi-square.
D) analysis of variance.

Question 21

In comparing differences in ratings of responsibility for an automobile accident between male and female drivers,the null hypothesis would be

A) men drive better than women.
B) there is no difference in ratings of responsibility between male and female drivers.
C) men are more responsible drivers than women.
D) there is a difference in ratings of responsibility between male and female drivers.

Question 22

How does sample size affect determinations of statistical significance? The ______ the sample,the _______.

A) larger;greater probability that the variable has an effect
B) smaller;greater probability that the variable has an effect
C) larger;the more confident you can be in your decision to reject or retain the null hypothesis
D) smaller;the more confident you can be in your decision to reject or retain the null hypothesis

Question 23

Leticia 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,Leticia will need to employ _____ statistics.

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

Question 24

Before conducting inferential statistics,Tim selects the probability level required for statistical significance.This level is referred to as the _____ of the test.

A) null hypothesis
B) research hypothesis
C) intuitive level
D) alpha level

Question 25

A researcher employs inferential statistics to examine the difference in mean scores obtained by fourth grade boys and girls on a standardized math test.Inferential statistics

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

Question 26

Inferential statistics allow us to arrive at conclusions about the _____ on the basis of _____ data.

A) population;sample
B) sample;population
C) independent variable;dependent variable
D) dependent variable;independent variable

Question 27

Deacon finds that,on the average,males have higher starting salaries than females.In order to conclude that the differences in starting salaries are true differences and not a result of random error,Deacon would employ the use of _____ statistics.

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

Question 28

Dr.Walters finds that students who work less than 10 hours a week have significantly higher test scores than students who work more than 10 hours a week.In order to determine the magnitude of the effect of work hours on test scores,she should calculate a(n)

A) critical value.
B) effect size.
C) null calculation.
D) degree of freedom.

Question 29

A manipulation check is especially important when

A) significant results are obtained.
B) nonsignificant results are obtained.
C) one-tailed tests are used.
D) two-tailed tests are used.

Question 30

Rejecting the null hypothesis when it is true is called a ________ error,whereas not rejecting a false null hypothesis is called a ________ error.

A) Type II;Type I
B) Type I;Type II
C) minor;major
D) significant;nonsignificant

Question 31

A Type I error is a decision to

A) reject the null hypothesis when it is false.
B) reject the null hypothesis when it is true.
C) not reject the null hypothesis when it is true.
D) not reject the null hypothesis when it is false.

Question 32

Which of the following is least correct regarding a Type II error? The probability of making a Type II error is

A) influenced by the probability of making a Type I error.
B) influenced by the size of the sample.
C) lessened with a large effect size.
D) equal to your alpha level.

Question 33

A Type II error is a decision to

A) reject the null hypothesis when it is false.
B) reject the null hypothesis when it is true.
C) not reject the null hypothesis when it is true.
D) not reject the null hypothesis when it is false.

Question 34

If Jack proposes that "there is a difference in hiring preferences between veterans and non-veterans," this represents the _____ hypothesis.If he proposes that "there is no difference in hiring preferences between veterans and non-veterans," this represents the _____ hypothesis.

A) null;research
B) research;null
C) inferential;descriptive
D) descriptive;inferential

Question 35

The t-test and F-test are used for which type of data?

A) Nominal
B) Ordinal
C) Interval
D) Ratio

Question 36

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

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

Question 37

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 was rated more comfortable with a mean of 5.5 than Mud Handler with a mean of 4.3.The Type I error would be to conclude that Trail Cushion was

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 identical in comfort.

Question 38

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 was rated more comfortable with a mean of 5.5 than Mud Handler with a mean of 4.3.The Type II error would be to conclude that Trail Cushion was

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 identical in comfort.

Question 39

If we say we have statistically significant results,we mean the results are

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 40

The _____ the t or F ratio,the more likely the results are _____.

A) larger;significant
B) smaller;significant
C) more correlated;dissimilar
D) more correlated;due to errors

Question 41

Jay calculates the 95% confidence interval for the difference between means.He finds the interval ranges from 1.85 to 4.08.What might Jay conclude from this finding?

A) 95% of the means have values of 1.85 and 4.08.
B) He is a 95% certain that the interval 1.85 to 4.08 contains the difference between means.
C) The results will not be significant 95% of the time.
D) 95% of the population will be confident in his results.

Question 42

When comparing two group means,the _____ refers to the number of scores free to vary once the means are known.

A) null hypothesis
B) research hypothesis
C) statistical significance
D) degrees of freedom

Question 43

In an examination of the strength of relationship between study time and test score,the null hypothesis would be

A) the true population correlation is greater than 0.00.
B) the true population correlation is less than 0.00.
C) the true population correlation is equal to 0.00.
D) the true population correlation is 1.00.

Question 44

A sampling distribution is a distribution of the kinds of outcomes one expects if the ________ hypothesis is ________.

A) null;true
B) null;false
C) research;true
D) research;false

Question 45

A researcher asked participants to rate the softness of two well-known brands of toilet tissue: Fuzzy and Luvvy.Fuzzy was rated softer than Luvvy with mean ratings of 5.50 and 3.25,respectively.This difference was statistically significant at the .05 probability level.The null hypothesis for the population was that

A) Fuzzy is softer than Luvvy.
B) Luvvy is softer than Fuzzy.
C) There is a difference between Fuzzy and Luvvy in softness.
D) There is no difference between the softness of Fuzzy and Luvvy tissues.

Question 46

_____ is/are used to tell you the probability that your results would be obtained again if you repeated the study on many occasions.

A) Descriptive statistics
B) Inferential statistics
C) The research hypothesis
D) The null hypothesis

Question 47

A researcher interested in the use of discipline practices by males versus females predicted that men would use power-oriented practices more frequently than women.The research hypothesis would be that

A) women use power techniques more than men.
B) men use power techniques more than women.
C) there is no difference between men and women in the use of discipline techniques.
D) there is a significant difference between men and women and the use of discipline techniques.

Question 48

A one-tailed statistical test is used when

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 49

In testing differences between means,the _____ hypothesis would suggest the population means are different.

A) null
B) research
C) practical
D) significant

Question 50

The likelihood of the occurrence of some event or outcome is referred to as

A) the null hypothesis.
B) the research hypothesis.
C) the significant hypothesis.
D) probability.

Question 51

In testing differences between means,the _____ hypothesis would suggest any observed difference is due to _____.

A) null;the manipulation
B) research;random error
C) practical;the manipulation
D) null;random error

Question 52

Variance within a sample is used as part of the calculation for which of the following statistical tests?

A) Chi-square
B) F-test
C) T-test
D) both F-test and t-test

Question 53

All statistical techniques rely on _____ to determine the probability that the results are consistent with the null hypothesis.

A) Type I error
B) Type II error
C) sampling distributions
D) statistical significance

Question 54

A researcher assesses the length of prison sentence assigned to a physically attractive or unattractive defendant.The researcher believes that attractive defendants will be assigned shorter prison sentences than unattractive defendants.The research hypothesis would be

A) there is no difference in the length of prison sentence received by attractive versus 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 difference in assigned length of prison sentence.

Question 55

What is the difference between descriptive and inferential statistics? Descriptive statistics ______,while inferential statistics ______.

A) use ratio data;use nominal data
B) use nominal data;use ratio data
C) summarize data;determine the probability that results are due to chance
D) determine the probability that results are due to chance;summarize data

Question 56

The statement that the independent variable had no effect is called the ________ hypothesis.

A) null
B) research
C) practical
D) significant

Question 57

The null hypothesis is rejected whenever

A) past studies prove it to be wrong.
B) there is a low probability that the obtained results could be due to random error.
C) there is a high probability that the obtained results could be due to random error.
D) the researcher is convinced that the variable is ineffective in causing changes in behaviour.

Question 58

Which of the following is least correct regarding the use of statistical tests?

A) A goal of the test is to allow you to make a decision about whether the obtained results would be repeatable.
B) You are more likely to obtain significant results with smaller sample sizes because they are easier to work with.
C) The significance level selected indicates how confident you want to be when making a decision.
D) You are most likely to obtain significant results when your effect size is large.

Question 59

Based on her use of inferential statistics,Martha believes that the difference in happiness scores between single versus married women in her study is a true difference.Thus,she would _____ and assume _____.

A) fail to reject the null;statistical significance
B) fail to reject the null;no statistical significance
C) reject the null;no statistical significance
D) reject the null;statistical significance

Question 60

A researcher was interested in differences in attitudes about marriage between men and women.She predicted that women would have different attitudes about marriage than men.What would be the null hypothesis?

A) Women have more positive attitudes than men.
B) Men have more positive attitudes than women.
C) There is no difference between men and women in their attitudes toward marriage.
D) Gender and attitude are not related.

Question 61

With three independent variables and a single dependent variable,the most appropriate statistical test to analyze the data would be a(n)

A) chi-square.
B) analysis of variance .
C) t-test
D) Pearson correlation.

Question 62

A researcher is interested in studying whether responses to lowering the legal age for drinking alcohol (for or against)varies by gender (male or female).Which statistical test would be most appropriate for this type of data?

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

Question 63

Jenny reports that individuals who follow her diet plan lose more weight than individuals who follow Richard's diet plan.In actuality,there is no difference in weight loss between those on Jenny's versus those on Richard's plan.Jenny's claim illustrates a _____ error.

A) Type IV
B) Type III
C) Type II
D) Type I

Question 64

Which statistical test would be most appropriate to examine the relationship between daily temperature and number of ice cream cones sold during the month of July?

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

Question 65

Fred has concluded that there is no difference in driving ability between drivers who have consumed 1 versus 3 cans of beer.However,there really is a difference in ability between the drivers.Fred has made a(n)_____ error.

A) null
B) alternative
C) Type I
D) Type II

Question 66

A researcher wants to determine if cholesterol level is lower for vegetarians versus non-vegetarians.Which statistical test would be most appropriate to analyze the data?

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