Deck 5: Introduction to Hypothesis Testing

Question 1

A researcher wants to know if a new type of health insurance works better or worse than a standard form of health insurance. The hypothesis that there will be no difference between the new type of insurance and the old type of insurance is called the:

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

Answer 1

null hypothesis

Question 2

The logic of hypothesis testing involves figuring out the probability of getting a particular result if:

A)the research hypothesis is true
B)the sampling distribution is accurate
C)the comparison distribution is true
D)the null hypothesis is true

Answer 2

the null hypothesis is true

Question 3

For the following question(s): A researcher is interested in a new kind of exercise. This new exercise can be done by anyone because it does not require any equipment, and therefore could be potentially beneficial without cost to the person. The researcher is interested in whether this new exercise will reduce the rate of heart attacks in the people who participate in doing it.
What is the "cutoff on the comparison distribution"?

A)The point at which, assuming the null hypothesis is true, it would be extremely unlikely to get a result this extreme.
B)The point at which, assuming the research hypothesis is true, it would be extremely unlikely to get a result this extreme.
C)The point at which the comparison distribution ends.
D)The point at which you accept the null hypothesis if the result is more extreme.

Answer 3

The point at which, assuming the null hypothesis is true, it would be extremely unlikely to get a result this extreme.

Question 4

For the following question(s): A researcher is interested in a new kind of exercise. This new exercise can be done by anyone because it does not require any equipment, and therefore could be potentially beneficial without cost to the person. The researcher is interested in whether this new exercise will reduce the rate of heart attacks in the people who participate in doing it.
What is the comparison distribution?

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

Question 5

A researcher tests whether there is any difference between how fast people work in the morning versus how fast they work in the evening. What is the NULL hypothesis?

A)People who work in the morning work faster.
B)People who work at night work faster.
C)There is some difference, but which is faster is not predicted.
D)There is no difference in the speed at which people work.

Question 6

A researcher tests effects of a new training program. The hypothesis that this new training program will work better than the old training program is called the:

A)comparison hypothesis
B)research hypothesis
C)null hypothesis
D)there is no special name for this kind of a hypothesis

Question 7

You want to know if a new employee incentive program really works. How would you test the hypothesis that it does work?

A)Try to disprove the hypothesis that it does work
B)Try to prove the hypothesis that it does work
C)Try to disprove the hypothesis that it does not work
D)Try to prove the hypothesis that it does not work

Question 8

A researcher tests whether a new teaching method is more effective than the old one. What is the RESEARCH hypothesis?

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 between the old teaching method and the new teaching method.
D)There is some difference in effectiveness between the old teaching method and the new teaching method, but which is more effective is not predicted.

Question 9

What is a hypothesis?

A)a procedure for using descriptive statistics in research
B)a set of theories about certain facts, relationships, or events
C)a prediction about the results of a research study
D)a way of quantifying the normal curve

Question 10

Place the five steps of the hypothesis-testing process in the correct order: 1. Determine the characteristics of the comparison distribution.
2) Decide whether to reject the null hypothesis.
3) Restate the question as a research hypothesis and a null hypothesis about the populations.
4) Determine your sample's score on the comparison distribution.
5) Determine the cutoff sample score on the comparison distribution at which the null hypothesis should be rejected.

A)2, 4, 1, 5, 3
B)3, 4, 1, 5, 2
C)1, 3, 5, 4, 2
D)3, 1, 5, 4, 2

Question 11

For the following question(s): A researcher is interested in a new kind of exercise. This new exercise can be done by anyone because it does not require any equipment, and therefore could be potentially beneficial without cost to the person. The researcher is interested in whether this new exercise will reduce the rate of heart attacks in the people who participate in doing it.
What is the research hypothesis?

A)People will 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 reduce the rate of heart attacks.
D)The exercise will increase the rate of heart attacks.

Question 12

For the following question(s): A researcher is interested in a new kind of exercise. This new exercise can be done by anyone because it does not require any equipment, and therefore could be potentially beneficial without cost to the person. The researcher is interested in whether this new exercise will reduce the rate of heart attacks in the people who participate in doing it.
What is the null hypothesis?

A)People will 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 reduce the rate of heart attacks.
D)The exercise will increase the rate of heart attacks.

Question 13

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

A)It is a central theme in the statistical analysis of virtually all social science research.
B)It is a simple part of statistics that applies to approximately 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 14

Another name for the research hypothesis is the:

A)null hypothesis
B)statistical hypothesis
C)void hypothesis
D)alternative hypothesis

Question 15

A _________________ is a set of principles that attempts to explain one or more facts, relations, or events.

A)curve
B)table
C)theory
D)deviation

Question 16

You determine the characteristics of the comparison distribution to answer which of the following questions?

A)Given a particular sample value, what is the probability of obtaining that value if the research hypothesis is true?
B)Given a particular sample value, what is the probability of obtaining that value if the null hypothesis is true?
C)Given a particular population value, what is the probability of obtaining that value if the research hypothesis is true?
D)Given a particular population value, what is the probability of obtaining that value if the null hypothesis is false?

Question 17

What represents the situation in which the null hypothesis is true?

A)the comparison distribution
B)the directional distribution
C)the nondirectional distribution
D)a one-tailed test

Question 18

A theory usually gives rise to various specific _____________ that can be tested in research studies.

A)t tests
B)hypotheses
C)Z scores
D)formulations

Question 19

A sample is studied 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 20

How do you set up a hypothesis testing problem?

A)You set it up to test what you predict will happen
B)You set it up to test the opposite of what you predict will happen
C)You set up two problems, one to test what you predict and the other to test the opposite
D)You set up a test that assumes the two populations are different, regardless of whether that is what you predict or not

Question 21

Suppose that a researcher wants to know if a new flu drug affects people, either by making them better or worse. Would this be a one-tailed or two-tailed test and why?

A)One-tailed because only one issue is discussed-the drug
B)One-tailed because there is only one interaction, which is between the flu and the drug
C)Two-tailed because there are two variables-whether or not people take the drug and how their flu is affected
D)Two-tailed because there is no predicted direction of the effect of the drug

Question 22

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

A)If the null hypothesis is in fact true, a failure to reject it will give stronger evidence in support of it.
B)One-tailed tests cannot be used in almost any real study involving two groups.
C)If an unexpected result comes out opposite to what is predicted, it does not have to be ignored.
D)A two-tailed test gives you a better chance of getting a significant result.

Question 23

The results of a study are not extreme enough to reject the null hypothesis. What can the researcher conclude with reasonable confidence?

A)Results support the null hypothesis.
B)Results prove that the null hypothesis is true.
C)Results support the research hypothesis.
D)None of the above; the results are inconclusive.

Question 24

Why can a researcher not say that the results PROVE that the research hypothesis is true?

A)Because the results of research studies are based on probabilities
B)Because the results of research studies are generally incorrect
C)Because it is likely that the results will be disproved within a short time
D)All of the above

Question 25

Based on the results of his study, a researcher rejects the null hypothesis because the probability of obtaining his result if the null hypothesis were true is less than 5%. How would this be symbolized?

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

Question 26

The cutoff sample score is also known as the:

A)critical value
B)sampling distribution
C)null value
D)sample Z score

Question 27

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)were inconclusive
D)support the null hypothesis

Question 28

A one-tailed test is especially associated with:

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

Question 29

Suppose the cutoff Z score on the comparison distribution is ±2.31. You could reject the null hypothesis if the sample value's Z score on this distribution was:

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

Question 30

A researcher reported significant results for a study, noting that ".05 > p." What is NOT standard about this expression?

A)")05" should have been written as "5%"
B)"p" should be Z
C)")05 > p" should have been written "p < .05"
D)nothing is wrong with this expression (it is standard)

Question 31

There is a special complication when using a two-tailed test. The researcher must:

A)multiply the significance percentage by .05
B)divide the significance percentage by .05
C)divide up the significance percentage between the two tails of the distribution
D)divide up the significance percentage by the four quartiles of the distribution

Question 32

A result is considered statistically significant when a sample value is so extreme that:

A)the research hypothesis is rejected
B)the null hypothesis is accepted
C)the research hypothesis is accepted
D)the null hypothesis is rejected

Question 33

What is the argument for using a one-tailed test when there is a clear basis for predicting a result in a given direction?

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 the sense that in using a one-tailed test it is harder to reject the null hypothesis.
D)A particular theory is being tested, and if the results come out opposite to the theory, that adds no more information than if the result simply had not been significant.

Question 34

The cutoff Z score on the comparison distribution is 1.64 and the sample value has a score of 1.32 on the comparison distribution.

A)the null hypothesis cannot be rejected
B)the null hypothesis is rejected
C)the research hypothesis is supported
D)the research hypothesis is rejected

Question 35

Which of the following is NOT a correct statement of one of the five steps of hypothesis testing?

A)Restate the question as a research hypothesis and a null hypothesis about the populations.
B)Determine the characteristics of the comparison distribution.
C)Determine the cutoff score on the sample distribution at which the research hypothesis should be rejected.
D)Decide whether to reject the null hypothesis.

Question 36

What does it mean if a researcher said she rejected the null hypothesis at the .05 level?

A)There was less than a 5% chance that she would have gotten such an extreme result by chance if the null hypothesis were true.
B)There was more than a 5% chance that she would have gotten such an extreme result by chance if the null hypothesis were true.
C)There is a 5% chance that there is a difference between the two populations she is testing if the null hypothesis were true.
D)There is a 95% chance that the research hypothesis is true.

Question 37

How do you determine whether or not to reject the null hypothesis?

A)If the Z score is less than -1 or greater than +1
B)If the Z score is greater than +2.5
C)Compare the Z score needed to reject the null hypothesis to the actual sample Z score
D)Compare the standard deviation of the sample to the standard deviation of the population

Question 38

What are the generally accepted cutoff points (or conventional levels of significance)in hypothesis testing in psychology?

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

Question 39

Which of the following is a standard way for the significance level of the result of a hypothesis test to be reported in a research article?

A)p < .01
B)p = .03
C)p < .05
D)all of the above are standard and can be used

Question 40

A researcher wants to know if a new type of exercise improves peoples' health. Would this be a one-tailed or two-tailed test and why?

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 take other factors into account
C)Two-tailed because they will have to study healthy and unhealthy people
D)Two-tailed because there is no predicted direction of difference

Question 41

In most behavioral and social science research articles, unless the researcher specifically states that a __________ test was used, it is assumed that it was a __________.

A)two-tailed; one-tailed
B).10 significance test; .25 significance test
C).05 significance test; .01 significance test
D)one-tailed; two-tailed

Question 42

In hypothesis testing, if the null hypothesis is rejected, this is taken as support for the __________.

Question 43

Decision errors are possible in hypothesis testing because you are making decisions about _______ based on information in ________.

A)distributions; Z tables
B)populations; samples
C)samples; populations
D)distributions; frequency tables

Question 44

__________ is a procedure for deciding whether the outcome of a study (results for a sample)supports a particular theory or practical innovation (which is thought to apply to a population).

Question 45

Suppose you conduct a study in which you set the significance level cutoff at a lenient probability level, such as 15%. In this case, you would have a 15% chance of making a:

A)Type I error
B)Type II error
C)Type III error
D)computational error

Question 46

In hypothesis testing, a statement that there is no difference between populations (or a difference opposite to that predicted)is called the __________.

Question 47

For a two-tailed test at the .05 significance level, the appropriate cutoff Z scores would be:

A)-1.96 and +1.96
B)-2.58 and +2.58
C)-1.64 and +1.64
D)-2.33 and +2.33

Question 48

Complete the table with the correct and incorrect decision-making terms in hypothesis testing:

A)1 = Type I error; 2 = correct decision; 3 = Type II error; 4 = computational error
B)1 = correct decision; 2 = Type I error; 3 = Type II error; 4 = correct decision
C)1 = Type I error; 2 = correct decision; 3 = correct decision; 4 = Type II error
D)1 = computational error; 2 = Type I error; 3 = Type II error; 4 = correct decision

Question 49

The usual rule in statistics is that a study cannot find the null hypothesis to be true-one can only reject or fails to reject the null hypothesis is simply uninformative and such studies tend not to be published. Why is this a problem in the field of psychology and other behavioral sciences?

A)Much work could be avoided if people knew what interventions had not worked.
B)This may lead to ideas being assumed as true just because a few studies found results supporting them (while many more, unreported, had not).
C)Power and effect size considerations are getting ignored.
D)Both A and B are correct.

Question 50

When a result is close but does not reach the significance level chosen , if may be reported as a "near significant trend" or as having "approached significance," with, for example,
p < .10. (True or False)

Question 51

Type II errors concern scientists because:

A)it could mean that a good theory or beneficial practice is not used
B)it means that the experiment must be repeated to confirm the positive result
C)rejecting the null hypothesis should only occur when the research hypothesis is true
D)future researchers might build entire theories based on a mistakenly significant result

Question 52

In hypothesis testing, a statement about the predicted relation between populations (often a prediction of difference between population means)is called the __________.

Question 53

Failing to reject the null hypothesis when the research hypothesis is true is referred to as:

A)the probability of rejection
B)the error term
C)a Type I error
D)a Type II error

Question 54

A __________ is a prediction about the results of a research study.

Question 55

In hypothesis testing, the __________ is the distribution to which you compare the score attained in your actual sample (based on the study results).

Question 56

A researcher is interested in the effect of going through a terrorist attack on the attitude of police officers about the goodness of people in New York City. After the attack, police may hold more positive attitudes about people (because of various acts of heroism and altruism exhibited by residents)or more negative attitudes because of negative outcomes (looting and dishonesty after the event). What type of hypothesis should the researcher make?

A)directional
B)significant
C)percentile
D)nondirectional

Question 57

Conventional levels of significance have been set at 5% and 1% in order to:

A)maximally protect against Type I error
B)maximally protect against Type II error
C)compromise between the risk of a Type I and Type II error
D)none of the above; these levels were set historically in an arbitrary way without regard to issues associated with Type I or Type II error

Question 58

Setting the significance level cutoff at .10 instead of the more usual .05 increases the likelihood of:

A)a Type I error
B)a Type II error
C)failing to reject the null hypothesis
D)accepting the null hypothesis when, in fact, it is false

Question 59

A Type I error is the result of:

A)improper measurement techniques on the part of the researcher
B)failing to reject the null hypothesis when, in fact, it is true
C)incorrectly rejecting the null hypothesis
D)incorrectly accepting the null hypothesis

Question 60

Setting the significance level at a very extreme cutoff (such as .001)increases the chances of:

A)getting a significant result
B)rejecting the null hypothesis
C)a Type I error
D)a Type II error

Question 61

The __________ distribution represents the situation if the null hypothesis is true.

Question 62

A study is done with a sample of one person. The general population (Population 2)has a mean of 30 and a standard deviation of 5. The cutoff Z score for significance in this study is a Z of 1.96. The raw score of the sample person is 45. What should you conclude? __________.

Question 63

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

Question 64

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

Question 65

For the following question(s): A study tests the prediction that people who spend a great deal of time on the beach have more eye problems than people in general.
The null hypothesis is _________.

Question 66

Most behavioral and social scientists use the ________ significance level, but those wanting to be more conservative commonly use the ________ levels.

Question 67

Before conducting a study, a researcher determines the cutoff sample score on the __________ distribution at which the null hypothesis would be rejected if the sample is more extreme than this cutoff score.

Question 68

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

Question 69

The 1% and 5% levels are the ________ levels of significance in behavioral and social science research.

Question 70

________ is a way of saying in symbols that a research result is significant at the .05 level.

Question 71

For the following question(s): A study tests the prediction that people who spend a great deal of time on the beach have more eye problems than people in general.
Population 1 refers to __________. Population 2 refers to people in general.

Question 72

If the value of the sample is more extreme than the _________ on the comparison distribution, then the null hypothesis will be rejected.

Question 73

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

Question 74

For the following question(s): A researcher wants to know whether people who listen regularly to radio talk shows are more or less likely to vote in national elections than are people in general.
The ________ is that there is no difference in voting between those who do and do not listen regularly to radio talk shows.

Question 75

In a(n)_________, the region of the comparison distribution in which the null hypothesis would be rejected is all on one side of the distribution.

Question 76

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

Question 77

If the cutoff represents the most extreme 5% of the comparison distribution, then 5% is called the __________ level.

Question 78

When testing a directional hypothesis, you use a(n)________ test.

Question 79

For the following question(s): A study tests the prediction that people who spend a great deal of time on the beach have more eye problems than people in general.
The research hypothesis is __________.

Question 80

A study is done with a sample of one person. In the general population (Population 2), Population M = 100 and Population SD = 8. The cutoff Z score for significance in this study is a Z of 1.64. The raw score of the sample is 110. What should you conclude? __________.