Deck 4: Introduction to Hypothesis Testing

Question 1

The "cutoff sample score on the comparison distribution" is the point at which

A)if the null hypothesis is true,a result this extreme is unlikely.
B)if the research hypothesis is true,a result this extreme is unlikely.
C)the comparison distribution ends.
D)the null hypothesis is accepted if the result is more extreme.

Answer 1

if the null hypothesis is true,a result this extreme is unlikely.

Question 2

A health psychologist is interested in the effectiveness of a new exercise on reducing the rate of heart attacks because the exercise requires no equipment and, therefore, can be done without cost.
What is the null hypothesis?

A)People will not participate because it does not cost them any money.
B)The exercise will make no difference in the rate of heart attacks.
C)The exercise will make no difference or will reduce the rate of heart attacks.
D)The exercise will make no difference or will increase the rate of heart attacks.

Answer 2

The exercise will make no difference or will increase the rate of heart attacks.

Question 3

When a result is not statistically significant,the correct decision is to

A)fail to reject the null hypothesis.
B)reject the null hypothesis.
C)fail to reject the research hypothesis.
D)reject the research hypothesis.

Answer 3

fail to reject the null hypothesis.

Question 4

How would a psychologist test the hypothesis that a new stress-reduction program really works?

A)Try to reject the hypothesis that it does work.
B)Try to accept the hypothesis that it does work.
C)Try to reject the hypothesis that it does not work.
D)Try to accept the hypothesis that it does not work.

Question 5

A psychologist who rejects the null hypothesis-because the probability of obtaining the results if the null hypothesis is true is less than 5%-would express this finding in symbols as

A)p = 5%
B)p < .05
C).05 < p
D)p > 5%

Question 6

The conventional levels of significance in hypothesis testing in psychology are

A).001 and .01
B).01 and .05
C).10,.20,and .30
D).05,.25,and .95

Question 7

When psychologists study a sample to see if it represents a population (called Population 1)that is different from a known population (called Population 2),the comparison distribution is

A)the same as the distribution of Population 1.
B)the same as the distribution of Population 2.
C)a rectangular distribution with the same mean and standard deviation as Population 1.
D)a rectangular distribution with the same mean and standard deviation as Population 2.

Question 8

A psychologist who states the hypothesis that there will be no difference between a new approach to therapy and the standard approach is stating a

A)comparison hypothesis.
B)research hypothesis.
C)null hypothesis.
D)differential hypothesis.

Question 9

When a psychologist rejects the null hypothesis at the .05 level,the results of a study indicate that

A)there is less than a 5% chance of getting such an extreme result if the null hypothesis is true.
B)there is more than a 5% chance of getting such an extreme result if the null hypothesis is true.
C)there is a 5% chance that the research hypothesis is true.
D)there is a 95% chance that the research hypothesis is true.

Question 10

If the cutoff Z score on the comparison distribution is ±2.31,a psychologist can reject the null hypothesis if the sample Z score on this distribution is

A)-2.16
B)-1.41
C)2.16
D)2.83

Question 11

A result is considered statistically significant when

A)the sample score is so extreme that the research hypothesis is rejected.
B)the sample score is so extreme that the null hypothesis is rejected.
C)the population mean is so extreme that the research hypothesis is rejected.
D)the population mean is so extreme that the null hypothesis is rejected.

Question 12

When a psychologist sets up a hypothesis testing problem,the intent is to

A)determine whether the predicted behavior will occur.
B)determine whether the opposite of the predicted behavior will occur.
C)test for two effects,the predicted behavior and the opposite behavior.
D)test the difference between two populations,regardless of the predicted behavior.

Question 13

A health psychologist is interested in the effectiveness of a new exercise on reducing the rate of heart attacks because the exercise requires no equipment and, therefore, can be done without cost.
What is the research hypothesis?

A)People will participate because it does not cost them any money.
B)The exercise will make a difference in the rate of heart attacks.
C)The exercise will reduce the rate of heart attacks.
D)The exercise will increase the rate of heart attacks.

Question 14

A health psychologist is interested in the effectiveness of a new exercise on reducing the rate of heart attacks because the exercise requires no equipment and, therefore, can be done without cost.
What is the comparison distribution?

A)the distribution of people who participate in the exercise program
B)the distribution of people who do not participate in the exercise program
C)the distribution of people who have heart attacks
D)the distribution of people who do not have heart attacks

Question 15

If a psychologist tests whether a new teaching method is more effective than the old one,the research hypothesis is that

A)the new teaching method is more effective than the old teaching method.
B)the old teaching method is more effective than the new teaching method.
C)there is no difference in effectiveness of the old and new teaching methods.
D)there is a difference in effectiveness between the two methods,but no prediction is made.

Question 16

If a psychologist tests whether there is any difference between how fast people work in the morning versus how fast they work in the evening,the null hypothesis is that

A)people who work in the morning work faster.
B)people who work at night work faster.
C)there is a difference in worker speed,but no prediction is made.
D)there is no difference in the speed at which people work.

Question 17

The decision to reject the null hypothesis using the Z test is made

A)if the Z score is less than -1 or greater than 1.
B)if the Z score is greater than 2.5.
C)by comparing the Z score needed to reject the null hypothesis to the actual Z score of the sample.
D)by comparing the standard deviation of the sample (SD)to the standard deviation of the population (σ).

Question 18

Rejecting the null hypothesis at the .05 level means that

A)there is more than a 5% chance of getting such an extreme result if the null hypothesis is true.
B)there is more than a 95% chance of getting such an extreme result if the research hypothesis is true.
C)there is less than a 5% chance of getting such an extreme result if the null hypothesis is true.
D)there is less than a 95% chance of getting such an extreme result if the research hypothesis is true.

Question 19

Which of the following statements is the most accurate description of hypothesis testing?

A)It is a central theme in the statistical analysis of virtually all psychology research.
B)It is a simple part of statistics that only applies to three statistical procedures.
C)It is a fairly uncommon way of using statistics.
D)It is a kind of statistical procedure that is used mainly as part of descriptive statistics.

Question 20

The distribution that represents the situation in which the null hypothesis is true is

A)the comparison distribution.
B)the sample distribution.
C)a two-tailed distribution.
D)a one-tailed distribution.

Question 21

A one-tailed test is associated with

A)the research hypothesis.
B)the null hypothesis.
C)a nondirectional hypothesis.
D)a directional hypothesis.

Question 22

If the cutoff Z score on the comparison distribution is ±1.96 and the sample Z score on the comparison distribution is -2.05,the correct decision is to

A)fail to reject the null hypothesis.
B)reject the null hypothesis.
C)accept the research hypothesis.
D)fail to accept the research hypothesis.

Question 23

The biggest complaint about significance tests is that they are

A)often misused.
B)mathematically inconsistent.
C)based on non-random samples.
D)difficult to learn.

Question 24

If the null hypothesis is rejected,the researcher can conclude that the results

A)support the research hypothesis.
B)prove that the research hypothesis is true.
C)are inconclusive.
D)support the null hypothesis.

Question 25

An increasingly common way to report the results of statistical tests in a research article is

A)p = .049
B)p > .05
C)p < .05
D)p < t

Question 26

A two-tailed test is associated with

A)the research hypothesis.
B)the null hypothesis.
C)a nondirectional hypothesis.
D)a directional hypothesis.

Question 27

When you have a directional hypothesis,the most conservative way to test it would be to use a(n)

A)one-tailed test in the predicted direction.
B)one-tailed test in the opposite-of-that-predicted direction.
C)one-tailed test,with the region of rejection in the positive tail.
D)two-tailed test.

Question 28

If the cutoff Z score on the comparison distribution is ±1.96,a psychologist CANNOT reject the null hypothesis if the sample Z score on this distribution is

A)-2.16
B)-1.41
C)2.16
D)2.83

Question 29

If a counseling psychologist wants to know if doubling the number of counseling sessions attended by students experiencing severe test anxiety will reduce or increase the amount of anxiety the students report just before a test,the statistical test the psychologist would use would be

A)one-tailed because only one issue is discussed-therapy sessions.
B)one-tailed because there is only one interaction between the therapy and anxiety.
C)two-tailed because there are two variables-whether or not students undergo therapy and how anxiety is affected.
D)two-tailed because the direction of the effect of increasing the amount of therapy is not predicted.

Question 30

A result that is statistically significant at the .05 level would be reported in a research article as

A)p = 5%
B)p > .05
C)p < .05
D)p < t

Question 31

If the cutoff Z score on the comparison distribution is 1.64 and the sample Z score is 1.32 on the comparison distribution,the correct decision is to

A)fail to reject the null hypothesis.
B)reject the null hypothesis.
C)accept the research hypothesis.
D)reject the research hypothesis.

Question 32

If you set alpha to .001 and are conducting a one-tailed test,what value do you need to look up in the normal curve table to determine the cutoff Z score on the comparison distribution?

A).005
B).001
C).0005
D).0001

Question 33

The correct argument for using a two-tailed test,even if there is a clear basis for predicting a result in a given direction,is that

A)if the null hypothesis is in fact true,rejecting it will provide stronger evidence in support of it.
B)one-tailed tests cannot be used in most studies involving one or two groups.
C)if an unexpected result that is opposite of what is predicted occurs,it does not have to be ignored.
D)a two-tailed test improves the chance of getting a statistically significant result.

Question 34

When the results of a study are not extreme enough to reject the null hypothesis,a psychologist can conclude with reasonable confidence that

A)the results support the null hypothesis.
B)the results prove that the null hypothesis is true.
C)the results support the research hypothesis.
D)the results are inconclusive.

Question 35

The correct argument for using a one-tailed test when there is a clear basis for predicting a result in a given direction is that

A)the underlying mathematics of one-tailed tests are more accurate.
B)if the result is opposite to the prediction,the researcher can still do a two-tailed test later.
C)it is more conservative in that one-tailed tests make rejecting the null hypothesis harder.
D)it is less conservative in that one-tailed tests make rejecting the null hypothesis easier.

Question 36

The first step of hypothesis testing involves specifying the

A)comparison distribution.
B)cutoff sample score.
C)populations and hypotheses.
D)sample's score on the comparison distribution.

Question 37

If you set alpha to .01 and are conducting a two-tailed test,what value do you need to look up in the normal curve table to determine the cutoff Z score on the comparison distribution?

A).020
B).010
C).005
D).001

Question 38

If the cutoff Z score on the comparison distribution is -1.64 and the sample Z score is 2.05 on the comparison distribution,the correct decision is to

A)fail to reject the null hypothesis.
B)reject the null hypothesis.
C)accept the research hypothesis.
D)fail to accept the research hypothesis.

Question 39

If a health psychologist wants to know if regular exercise improves people's health,the type of hypothesis the psychologist would use is

A)one-tailed because the study is only interested in whether the exercise increases health.
B)one-tailed because the study only looks at the effects of exercise and does not consider other factors.
C)two-tailed because the study will have to involve both healthy and unhealthy people.
D)two-tailed because no direction for any observed difference has been predicted.

Question 40

A major misuse of significance tests is the tendency to

A)decide that if a result is not significant,the null hypothesis is shown to be true.
B)decide that the null hypothesis is false when the results obtained are not significant.
C)accept the research hypothesis when the results are not significant.
D)claim that a non-significant result is the same as an unimportant result.

Question 41

The situation in which the null hypothesis is true is represented by the __________ distribution.

Question 42

In psychological research,the 1% and 5% levels are the __________ levels of significance.

Question 43

Hypothesis testing is a systematic procedure for determining whether results of an experiment conducted using a sample support a particular theory that is thought to be applicable to a(n)__________.

Question 44

A set of principles that attempt to explain a set of facts,relationships,or events is a(n)__________.

Question 45

The researchers would use a(n)__________-tailed test.

Question 46

In hypothesis testing,a statement that there is no difference between populations is the __________.

Question 47

"People who spend a great deal of time on the beach do not have more eye problems than people in general" is the __________ hypothesis.

Question 48

The null hypothesis will be rejected when the sample's score is more extreme than the __________ on the comparison distribution.

Question 49

When the null hypothesis is rejected,the results of a study are said to be __________.

Question 50

Sometimes,a research hypothesis may be referred to as a(n)__________.

Question 51

A contrived statement set up to examine whether it can be rejected as part of the hypothesis-testing process is the __________.

Question 52

In hypothesis testing,a statement about the predicted relation between populations is the __________.

Question 53

"People who spend a great deal of time on the beach have more eye problems than people in general" is the __________ hypothesis.

Question 54

Most psychologists use the __________ significance level,but those wanting to be more conservative may use the __________ level.

Question 55

If Population 2 refers to people in general,Population 1 refers to __________.

Question 56

The most widely used procedure of inferential statistics used in psychology is __________.

Question 57

"There is no difference in voting between those who do and do not listen regularly to radio talk shows" is the __________ hypothesis.

Question 58

For a nondirectional research hypothesis,the null hypothesis is expressed in symbols as __________.

Question 59

If the cutoff sample score is set for the most extreme 5% of the comparison distribution,then 5% is called the __________ level.

Question 60

The comparison distribution is based on the distribution of the voting behavior of __________.

Question 61

A nutritionist wants to determine whether people who regularly drink one protein shake per day have lower cholesterol than people in general.In the general population,cholesterol is normally distributed with μ = 190 and σ = 30.A person who has followed the protein shake regimen for two months is randomly selected,and his cholesterol is 135.The nutritionist reported this result as "p < .01".Is the nutritionist's claim accurate?
a.Use the five steps of hypothesis testing to verify the nutritionist's claim.
b.Explain the result to someone who is familiar with mean,SD,Z scores,normal curve percentages,probability,and samples and populations,but not with hypothesis testing.

Question 62

The region of the comparison distribution in which the null hypothesis will be rejected is all on one side of the distribution for a(n)__________.

Question 63

A dermatologist is interested in whether a new treatment for poison ivy would reduce symptoms more quickly than the current treatment.In general,the current treatment completely eliminates symptoms after an average of 6 days,with a standard deviation of 1.2 days.One randomly selected patient given the new treatment had no symptoms after 5 days.Using the .05 level of significance,is the new treatment faster than the current one?
a.Use the five steps of hypothesis testing.
b.Sketch the distributions involved.
c.Explain the logic of what you did to a person who is familiar with graphs of distributions,the mean,standard deviation,Z scores,the normal curve and normal curve tables,and the basics of probability,but knows nothing else about statistics.Be sure your explanation includes the overall logic of hypothesis testing including each of the five steps.

Question 64

A popular music magazine has speculated that the average length of a song on one of today's popular CDs is 3.75 minutes with a standard deviation of 0.75 minutes.A randomly selected song of a particular new type of music is 5 minutes.Using the .05 level of significance,is this new type of music,represented by this one song,longer than popular songs in general?
a.Use the five steps of hypothesis testing.
b.Sketch the distributions involved.
c.Explain the logic of what you did to a person who is familiar with graphs of distributions,the mean,standard deviation,Z scores,the normal curve and normal curve tables,and the basics of probability,but knows nothing else about statistics.Be sure your explanation includes the overall logic of hypothesis testing including each of the five steps.

Question 65

Some researchers propose that significance testing should be banned and suggest using a different approach such as __________.

Question 66

A forensic psychologist studying the accuracy of a new type of polygraph (lie detector)test instructed a participant ahead of time to lie about some of the questions asked by the polygraph operator.On average,the current polygraph test is 75% accurate,with a standard deviation of 6.5%.With the new machine,the operator correctly identified 83.5% of the false responses.Using the .05 level of significance,is the accuracy of the new polygraph different from the current one?
a.Use the five steps of hypothesis testing.
b.Sketch the distributions involved.
c.Explain the logic of what you did to a person who is familiar with graphs of distributions,the mean,standard deviation,Z scores,the normal curve and normal curve tables,and the basics of probability,but knows nothing else about statistics.Be sure your explanation includes the overall logic of hypothesis testing including each of the five steps.

Question 67

The research hypothesis predicting that one population will have higher scores than the other is a(n)__________ hypothesis.

Question 68

A research hypothesis that does not predict a particular direction of difference between populations is called a(n)__________ hypothesis.

Question 69

For a directional research hypothesis,the null hypothesis is expressed in symbols as __________.

Question 70

The general population (Population 2)has a mean of 30 and a standard deviation of 5,and the cutoff Z score for significance in a study involving one participant is 1.96.If the raw score obtained by the participant is 45,what decisions should be made about the null and research hypotheses?

Question 71

The general population (Population 2)has μ = 100 and σ = 8,and the cutoff Z score for significance in a study involving one participant is 1.64.If the raw score obtained by the participant is 110,what decisions should be made about the null and research hypotheses?