Deck 10: Hypothesis Testing, Effect Size, and and Confidence Intervals: Two-Sample Designs

Question 1

The simple experiment described in Chapter 10 compared only two groups.

Answer 1

True

Question 2

In the simple experiment described by your text, the groups were made equivalent with a two step process of matching and review.

Answer 2

False

Question 3

The t test was developed as a way to analyze data from experiments with rats in mazes.

Answer 3

False

Question 4

The two kinds of t tests described in Chapter 10 were independent samples and paired samples.

Question 5

The denominator of an independent-samples t test is a standard error of a difference.

Question 6

To be a small effect size, d must be .05 or less.

Question 7

To capture the size of the difference between two population means, your textbook used an effect size index.

Question 8

The formula for power is 1 - $\mu$ .

Question 9

Your textbook recommends sample sizes of 30 or more to ensure that the p values from a t test be reliable.

Question 10

The alternative hypothesis is called the hypothesis of no difference.

Question 11

In the simple experiment described by your text, the groups were made equivalent with random assignment.

Question 12

The t test was developed as a way to analyze flavors in taste experiments.

Question 13

The two kinds of t tests described in Chapter 10 were independent samples and orthogonal samples.

Question 14

The denominator of a paired-samples t test is a standard error of a difference.

Question 15

A value of d such as 0.50 indicates a medium effect size.

Question 16

To capture the size of the difference between two population means, your textbook used confidence intervals.

Question 17

The formula for power is 1 - $\mu$ .

Question 18

Both $\alpha$ and N help determine the amount of power a t test has.

Question 19

Normally distributed populations with equal variances are most likely to give accurate p values for a t test.

Question 20

The null hypothesis states that the sample means are identical.

Question 21

In the simple experiment described by your text, extraneous variables were controlled using random assignment.

Question 22

The t test was developed as a way to determine how well data fit the normal curve.

Question 23

The two kinds of t tests described in Chapter 10 were power samples and paired samples.

Question 24

The numerator of an independent-samples t test is a standard error of a difference.

Question 25

Values of d greater than 1.00 indicate a large effect size.

Question 26

A confidence interval about a mean difference gives a degree of confidence about the difference between two population means.

Question 27

The formula for power is 1 - $\mu$ .

Question 28

As the value of p goes down, the value of d goes up.

Question 29

Data Set 10-1: A college teacher was assigned 4 freshmen advisees. He administered an attitude scale that measured liberalism-conservatism. Four years later, just before graduation, all 4 took the same scale again. High scores indicate conservative attitude. The following scores were obtained.
$$\begin{array} { c c } 2006 & 2010 \\\hline 26 & 15 \\22 & 23 \\17 & 14 \\15 & 10\end{array}$$

-The standard error of the difference for Data Set 10-1 is

A) 2.50
B) 3.69
C) 5.00

Question 30

Data Set 10-1: A college teacher was assigned 4 freshmen advisees. He administered an attitude scale that measured liberalism-conservatism. Four years later, just before graduation, all 4 took the same scale again. High scores indicate conservative attitude. The following scores were obtained.
$$\begin{array} { c c } 2006 & 2010 \\\hline 26 & 15 \\22 & 23 \\17 & 14 \\15 & 10\end{array}$$

-A t test of Data Set 10-1 would result in a t value of

A) 1.60
B) 0.90
C) 0.61
D) 1.80

Question 31

Data Set 10-1: A college teacher was assigned 4 freshmen advisees. He administered an attitude scale that measured liberalism-conservatism. Four years later, just before graduation, all 4 took the same scale again. High scores indicate conservative attitude. The following scores were obtained.
$$\begin{array} { c c } 2006 & 2010 \\\hline 26 & 15 \\22 & 23 \\17 & 14 \\15 & 10\end{array}$$

-The proper conclusion for the experiment described in Data Set 10-1 is

A) there was a significant shift in attitudes from conservative to liberal (p < .05)
B) there was a significant shift in attitudes from liberal to conservative (p < .05)
C) there was no significant shift in attitudes.

Question 32

Data Set 10-1: A college teacher was assigned 4 freshmen advisees. He administered an attitude scale that measured liberalism-conservatism. Four years later, just before graduation, all 4 took the same scale again. High scores indicate conservative attitude. The following scores were obtained.
$$\begin{array} { c c } 2006 & 2010 \\\hline 26 & 15 \\22 & 23 \\17 & 14 \\15 & 10\end{array}$$

-The effect size index for Data Set 10-1 is

A) 0.45
B) 0.90
C) 3.60

Question 33

Data Set 10-2: The IQs of a group of special education students were compared to the IQs of their siblings who were not in special education. The following data were obtained.
$$\begin{array} { c c } \text { Special Ed } & \text { Not Special Ed } \\\hline 70 & 104 \\65 & 99 \\67 & 95\end{array}$$

-The study described in Data Set 10-2 is an example of

A) an independent samples design
B) a paired-samples design
C) comparing a sample mean to a known population mean
D) unknown more information is required in order to decide, namely

Question 34

Data Set 10-2: The IQs of a group of special education students were compared to the IQs of their siblings who were not in special education. The following data were obtained.
$$\begin{array} { c c } \text { Special Ed } & \text { Not Special Ed } \\\hline 70 & 104 \\65 & 99 \\67 & 95\end{array}$$

-The standard error of the difference for Data Set 10-2 is

A) 16.00
B) 4.00
C) 2.00
D) 1.00

Question 35

Data Set 10-2: The IQs of a group of special education students were compared to the IQs of their siblings who were not in special education. The following data were obtained.
$$\begin{array} { c c } \text { Special Ed } & \text { Not Special Ed } \\\hline 70 & 104 \\65 & 99 \\67 & 95\end{array}$$

-The conclusion from Data Set 10-2 is that those in special education

A) have significantly lower IQs than those not in special education
B) have significantly higher IQs than those not in special education
C) are not significantly different in IQ than those not in special education.

Question 36

Data Set 10-2: The IQs of a group of special education students were compared to the IQs of their siblings who were not in special education. The following data were obtained.
$$\begin{array} { c c } \text { Special Ed } & \text { Not Special Ed } \\\hline 70 & 104 \\65 & 99 \\67 & 95\end{array}$$

-The numerical value of the effect size index for Data Set 10-2 is

A) 0. to .50
B) 0.51 to 1.00
C) 1.01 to 3.00
D) 3.01 to 10.00
E) greater than 10.

Question 37

Data Set 10-3: An experimenter matched by weight four pairs of volunteers. One member of each pair was randomly assigned to one of the two groups. One group fasted for 24 hours and the other for 48 hours. Scores below represent the number of ounces of Yummi (very vanilla) consumed during the first 10 minutes after the fast. Test for a difference at the .05 level.
$$\begin{array} { c c } 24 \text { hours } & 48 \text { hours } \\\hline 26 & 18 \\35 & 24 \\23 & 17 \\30 & 14\end{array}$$

-The experiment described in Data Set 10-3 is an example of

A) a paired samples design
B) an independent samples design
C) determining the probability that a sample was drawn from a population with a known mean
D) cannot be determined from the information given.

Question 38

Data Set 10-3: An experimenter matched by weight four pairs of volunteers. One member of each pair was randomly assigned to one of the two groups. One group fasted for 24 hours and the other for 48 hours. Scores below represent the number of ounces of Yummi (very vanilla) consumed during the first 10 minutes after the fast. Test for a difference at the .05 level.
$$\begin{array} { c c } 24 \text { hours } & 48 \text { hours } \\\hline 26 & 18 \\35 & 24 \\23 & 17 \\30 & 14\end{array}$$

-The standard error of the difference for Data Set 10-3 is

A) 3.34
B) 4.69
C) 4.35
D) 2.17

Question 39

Data Set 10-3: An experimenter matched by weight four pairs of volunteers. One member of each pair was randomly assigned to one of the two groups. One group fasted for 24 hours and the other for 48 hours. Scores below represent the number of ounces of Yummi (very vanilla) consumed during the first 10 minutes after the fast. Test for a difference at the .05 level.
$$\begin{array} { c c } 24 \text { hours } & 48 \text { hours } \\\hline 26 & 18 \\35 & 24 \\23 & 17 \\30 & 14\end{array}$$

-The conclusion from Data Set 10-3 is that

A) the more you fast the less you eat
B) the more you fast the more you eat
C) there is no significant difference in the amount eaten if you haven't eaten for 24 or 48 hours
D) additional information is needed namely .

Question 40

Data Set 10-3: An experimenter matched by weight four pairs of volunteers. One member of each pair was randomly assigned to one of the two groups. One group fasted for 24 hours and the other for 48 hours. Scores below represent the number of ounces of Yummi (very vanilla) consumed during the first 10 minutes after the fast. Test for a difference at the .05 level.
$$\begin{array} { c c } 24 \text { hours } & 48 \text { hours } \\\hline 26 & 18 \\35 & 24 \\23 & 17 \\30 & 14\end{array}$$

-The effect size index for Data Set 10-3 is

A) 0.77
B) 1.53
C) 3.07
D) 2.36

Question 41

Data Set 10-4: Gerbils were used to assess the effect of Natural Neutral, a drug designed to reduce emotionality in high-drive people. Each of 20 gerbils spent 10 solitary minutes in an open field. The investigator recorded the number of fecal boluses for each animal. Then each animal was given an injection of Natural Neutral and the open field task was repeated. The following data were produced (large numbers indicate high emotionality).
$$\begin{array} { l l l } & \text { No Drug } & \text { Drug } \\ \text { mean number of boluses } & 6 & 8 \\\text { standard deviation of boluses } & 2 & 2 \\\end{array}$$
$\text { correlation coefficient between Drug and No Drug Score } = .50$

-The design in Data Set 10-4 is one of

A) paired samples
B) independent samples
C) testing the significance of a correlation
D) none of the other alternatives are correct.

Question 42

Data Set 10-4: Gerbils were used to assess the effect of Natural Neutral, a drug designed to reduce emotionality in high-drive people. Each of 20 gerbils spent 10 solitary minutes in an open field. The investigator recorded the number of fecal boluses for each animal. Then each animal was given an injection of Natural Neutral and the open field task was repeated. The following data were produced (large numbers indicate high emotionality).
$$\begin{array} { l l l } & \text { No Drug } & \text { Drug } \\ \text { mean number of boluses } & 6 & 8 \\\text { standard deviation of boluses } & 2 & 2 \\\end{array}$$
$\text { correlation coefficient between Drug and No Drug Score } = .50$

-The proper conclusion from Data Set 10-4 is that Natural Neutral

A) reduces emotionality
B) increases emotionality
C) has no significant effect on emotionality.

Question 43

Data Set 10-5: This experiment is modeled after part of the data needed to demonstrate the Hawthorne Effect. Four assembly-line workers, who normally had two coffee breaks and an hour for lunch, participated in a week-long experiment in which they gave up both coffee breaks and half their lunch hour. Productivity (units produced per hour) for these four was measured under both conditions and is shown below. $$\begin{array} { c c } { \text { Productivity/hour } } \\\text { Leisurely Schedule } & \text { Rushed Schedule } \\\hline 6 & 6 \\3 & 5 \\4 & 5 \\5 & 6\end{array}$$

-The experiment described in Data Set 10-5

A) is an independent samples design
B) is a paired samples design
C) isn't given in enough detail to determine the design.

Question 44

Data Set 10-5: This experiment is modeled after part of the data needed to demonstrate the Hawthorne Effect. Four assembly-line workers, who normally had two coffee breaks and an hour for lunch, participated in a week-long experiment in which they gave up both coffee breaks and half their lunch hour. Productivity (units produced per hour) for these four was measured under both conditions and is shown below. $$\begin{array} { c c } { \text { Productivity/hour } } \\\text { Leisurely Schedule } & \text { Rushed Schedule } \\\hline 6 & 6 \\3 & 5 \\4 & 5 \\5 & 6\end{array}$$

-The t value for Data Set 10-5 is

A) less than 1.00
B) 1.00-1.99
C) 2.00-2.99
D) 3.00-4.00
E) greater than 4.00.

Question 45

Data Set 10-5: This experiment is modeled after part of the data needed to demonstrate the Hawthorne Effect. Four assembly-line workers, who normally had two coffee breaks and an hour for lunch, participated in a week-long experiment in which they gave up both coffee breaks and half their lunch hour. Productivity (units produced per hour) for these four was measured under both conditions and is shown below. $$\begin{array} { c c } { \text { Productivity/hour } } \\\text { Leisurely Schedule } & \text { Rushed Schedule } \\\hline 6 & 6 \\3 & 5 \\4 & 5 \\5 & 6\end{array}$$

-The proper conclusion for Data Set 10-5 is that the leisurely schedule results in productivity that is

A) significantly greater than a rushed schedule
B) significantly less than a rushed schedule
C) not significantly different from a rushed schedule

Question 46

Data Set 10-5: This experiment is modeled after part of the data needed to demonstrate the Hawthorne Effect. Four assembly-line workers, who normally had two coffee breaks and an hour for lunch, participated in a week-long experiment in which they gave up both coffee breaks and half their lunch hour. Productivity (units produced per hour) for these four was measured under both conditions and is shown below. $$\begin{array} { c c } { \text { Productivity/hour } } \\\text { Leisurely Schedule } & \text { Rushed Schedule } \\\hline 6 & 6 \\3 & 5 \\4 & 5 \\5 & 6\end{array}$$

-The effect size index for Data Set 10-5 is

A) 1.23
B) 2.04
C) 2.45

Question 47

Data Set 10-6: Drugs used in treating schizophrenia all block the reception of dopamine by neurons. (Dopamine is a neurotransmitter, which, when released by the axons of one nerve, inhibits the firing of the next nerve.) This fact led to the idea that schizophrenia occurs when too much dopamine is produced. Suppose the following data on dopamine production were obtained.
$$\begin{array} { c c } \text { Schizophrenics } & \text { Control Group } \\\hline 42 & 33 \\31 & 27 \\29 & 18\end{array}$$

-The study described in Data Set 10-6 is an example of

A) an independent-samples design
B) a paired-samples design
C) comparing a sample mean to a known population mean
D) unknown more information is required in order to decide, namely

Question 48

Data Set 10-6: Drugs used in treating schizophrenia all block the reception of dopamine by neurons. (Dopamine is a neurotransmitter, which, when released by the axons of one nerve, inhibits the firing of the next nerve.) This fact led to the idea that schizophrenia occurs when too much dopamine is produced. Suppose the following data on dopamine production were obtained.
$$\begin{array} { c c } \text { Schizophrenics } & \text { Control Group } \\\hline 42 & 33 \\31 & 27 \\29 & 18\end{array}$$

-The standard error of the difference for Data Set 10-6 is

A) 5.94
B) 2.00
C) 1.63
D) 1.16

Question 49

Data Set 10-6: Drugs used in treating schizophrenia all block the reception of dopamine by neurons. (Dopamine is a neurotransmitter, which, when released by the axons of one nerve, inhibits the firing of the next nerve.) This fact led to the idea that schizophrenia occurs when too much dopamine is produced. Suppose the following data on dopamine production were obtained.
$$\begin{array} { c c } \text { Schizophrenics } & \text { Control Group } \\\hline 42 & 33 \\31 & 27 \\29 & 18\end{array}$$

-The conclusion from Data Set 10-6 (which is the same arrived at by some of the actual research) is that schizophrenics

A) have significantly more dopamine than the control group
B) have significantly less dopamine than the control group
C) and control groups don't differ significantly in dopamine.

Question 50

Data Set 10-6: Drugs used in treating schizophrenia all block the reception of dopamine by neurons. (Dopamine is a neurotransmitter, which, when released by the axons of one nerve, inhibits the firing of the next nerve.) This fact led to the idea that schizophrenia occurs when too much dopamine is produced. Suppose the following data on dopamine production were obtained.
$$\begin{array} { c c } \text { Schizophrenics } & \text { Control Group } \\\hline 42 & 33 \\31 & 27 \\29 & 18\end{array}$$

-The effect size index for Data Set 10-6 is

A) 0.26
B) 0.78
C) 1.55
D) 2.58

Question 51

Data Set 10-7: In that long standing feud between the Hatfields and the McCoys, Old Doc Sawbones has been keeping score. During the last 16 years he noted in his feudian notebook a "degree of injury"
measure each time he patched up, sewed up, or made a coroner's report on anyone in the two families. Summary statistics were:
$$\begin{array} { c c c } & \text { Hatfields } & \text { McCoys } \\\bar { X } & 41 & 34 \\\hat { S } & 6 & 8 \\N & 16 & 16\end{array}$$

-The design of the study described in Data Set 10-7 is

A) independent samples
B) paired samples
C) comparing a sample mean to a population mean
D) not enough information is given.

Question 52

Data Set 10-7: In that long standing feud between the Hatfields and the McCoys, Old Doc Sawbones has been keeping score. During the last 16 years he noted in his feudian notebook a "degree of injury"
measure each time he patched up, sewed up, or made a coroner's report on anyone in the two families. Summary statistics were:
$$\begin{array} { c c c } & \text { Hatfields } & \text { McCoys } \\\bar { X } & 41 & 34 \\\hat { S } & 6 & 8 \\N & 16 & 16\end{array}$$

-The standard error of the difference of the data in Data Set 10-7 is

A) 6.25
B) 1.87
C) 0.625
D) 2.50

Question 53

Data Set 10-7: In that long standing feud between the Hatfields and the McCoys, Old Doc Sawbones has been keeping score. During the last 16 years he noted in his feudian notebook a "degree of injury"
measure each time he patched up, sewed up, or made a coroner's report on anyone in the two families. Summary statistics were:
$$\begin{array} { c c c } & \text { Hatfields } & \text { McCoys } \\\bar { X } & 41 & 34 \\\hat { S } & 6 & 8 \\N & 16 & 16\end{array}$$

-Which of the following conclusions is proper for Data Set 10-7?

A) The Hatfields had a significantly higher injury score than the McCoys
B) The McCoys had a significantly higher injury score than the Hatfields
C) There was no significant difference between the Hatfields and the McCoys
D) Not enough information is contained in Data Set 10-7 to support one of the other alternatives.

Question 54

Data Set 10-7: In that long standing feud between the Hatfields and the McCoys, Old Doc Sawbones has been keeping score. During the last 16 years he noted in his feudian notebook a "degree of injury"
measure each time he patched up, sewed up, or made a coroner's report on anyone in the two families. Summary statistics were:
$$\begin{array} { c c c } & \text { Hatfields } & \text { McCoys } \\\bar { X } & 41 & 34 \\\hat { S } & 6 & 8 \\N & 16 & 16\end{array}$$

-The effect size index for Data Set 10-7 is

A) 0.70
B) 0.99
C) 1.40

Question 55

Data Set 10-8: Drugs that reduce emotionality make big money for drug companies. These drugs undergo extensive testing, some of which is done with animals. One common test of emotionality in rats is the number of fecal boluses that are dropped when an animal is left for 10 minutes in an open field (a 4' x 4' space). Greater emotionality is indicated by more boluses. Imagine that two drugs, aloe and vera were compared. Five rats were given aloe and five were given vera. The numbers below represent the number of boluses dropped in the open field. $$\begin{array} { r l } \text { Aloe } & \text { Vera } \\\hline 4 & 2 \\12 & 9 \\7 & 6 \\10 & 7 \\6 & 4\end{array}$$

-The experimenter described in Data Set 10-8 is an example of

A) a paired samples design
B) an independent samples design
C) determining the probability that a sample was drawn from a population with a known mean
D) cannot be determined from the information given.

Question 56

Data Set 10-8: Drugs that reduce emotionality make big money for drug companies. These drugs undergo extensive testing, some of which is done with animals. One common test of emotionality in rats is the number of fecal boluses that are dropped when an animal is left for 10 minutes in an open field (a 4' x 4' space). Greater emotionality is indicated by more boluses. Imagine that two drugs, aloe and vera were compared. Five rats were given aloe and five were given vera. The numbers below represent the number of boluses dropped in the open field. $$\begin{array} { r l } \text { Aloe } & \text { Vera } \\\hline 4 & 2 \\12 & 9 \\7 & 6 \\10 & 7 \\6 & 4\end{array}$$

-The standard error of difference for Data Set 10-8 is

A) 0.374
B) 0.837
C) 1.871
D) 3.50

Question 57

Data Set 10-8: Drugs that reduce emotionality make big money for drug companies. These drugs undergo extensive testing, some of which is done with animals. One common test of emotionality in rats is the number of fecal boluses that are dropped when an animal is left for 10 minutes in an open field (a 4' x 4' space). Greater emotionality is indicated by more boluses. Imagine that two drugs, aloe and vera were compared. Five rats were given aloe and five were given vera. The numbers below represent the number of boluses dropped in the open field. $$\begin{array} { r l } \text { Aloe } & \text { Vera } \\\hline 4 & 2 \\12 & 9 \\7 & 6 \\10 & 7 \\6 & 4\end{array}$$

-The proper conclusion from Data Set 10-8 is that

A) aloe reduces emotionality more than vera
B) vera reduces emotionality more than aloe
C) there is no significant difference in the effect of the two drugs on emotionality
D) there is a significant change in emotionality, but the direction cannot be determined.

Question 58

Data Set 10-8: Drugs that reduce emotionality make big money for drug companies. These drugs undergo extensive testing, some of which is done with animals. One common test of emotionality in rats is the number of fecal boluses that are dropped when an animal is left for 10 minutes in an open field (a 4' x 4' space). Greater emotionality is indicated by more boluses. Imagine that two drugs, aloe and vera were compared. Five rats were given aloe and five were given vera. The numbers below represent the number of boluses dropped in the open field. $$\begin{array} { r l } \text { Aloe } & \text { Vera } \\\hline 4 & 2 \\12 & 9 \\7 & 6 \\10 & 7 \\6 & 4\end{array}$$

-The effect size index for Data Set 10-8 is

A) 2.62
B) 1.18
C) 0.70
D) 1.05

Question 59

For a simple experiment, which of the following is true?

A) As a null hypothesis, assume that the two groups represent different populations.
B) Apply the dependent variable to both groups and then measure the changes in the independent variable.
C) Find the probability that the two samples are from different populations by using a t distribution.
D) Treat both groups exactly alike except for one thing.

Question 60

The book's description of an experiment included the phrase, "treat them exactly alike except for one thing."The italicized phrases are related to a(n)_________ variable and a(n)_________ variable, respectively.

A) independent, dependent
B) dependent, independent
C) extraneous, independent
D) dependent, extraneous.

Question 61

In a simple experiment, treat two groups exactly the same except for one thing and then measure the individuals in both groups on some scale. Treating the two groups differently on the one thing constitutes

A) the independent variable
B) the dependent variable
C) an extraneous variable
D) none of the other alternatives are correct.

Question 62

Which of these phrases is not like the others? Which of these phrases doesn't belong with the other three?

A) independent variable
B) dependent variable
C) experimental group
D) treatment.

Question 63

Which of these phrases doesn't belong with the other three?

A) extraneous variable
B) independent variable
C) treatment
D) experimental group.

Question 64

With an acknowledgment to Sesame Street, "Which of these things is not like the others, which of these things doesn't belong?"

A) repeated measures
B) natural pairs
C) independent samples
D) matched pairs.

Question 65

According to your text, the reason we do experiments is to be able to tell

A) whether all extraneous variables were controlled
B) whether the samples were representative of the population
C) how scores on the dependent variable are affected by the independent variable
D) all of the other alternatives are correct.

Question 66

The notion of generalizing from an experiment to a population was described by your text as the of an experiment.

A) prima facie
B) quid pro quid
C) modus tollens
D) raison d'etre.

Question 67

According to your text is the reason for doing an experiment.

A) performing an inferential statistics test
B) being able to make statements that are more inclusive than those possible from the sample alone
C) determining just what the facts are in the case at hand
D) determining what percent of the results is due to chance.

Question 68

Null hypothesis statistical testing (NHST) allows you to conclude that the null hypothesis is

A) probably true
B) true
C) probably false
D) any of the other alternatives, depending on the value of p.

Question 69

The logic of null hypothesis statistical testing (NHST) is to

A) assume that two populations have equal means and then demonstrate that they areprobably equal
B) assume that two populations have unequal means and then demonstrate that they areprobably unequal
C) assume that two populations have equal means and then demonstrate that they areprobably unequal
D) assume that two populations have unequal means and then demonstrate that they areprobably equal.

Question 70

The logic of null hypothesis statistical testing (NHST) is to assume that two populations have

A) means that are equal and then see if sample data will permit you to conclude that they are probably equal
B) means that are equal and then see if sample data will permit you to conclude that they are probably unequal
C) means that are not equal and then see if sample data will permit you to conclude that they are probably unequal
D) means that are not equal and then see if sample data will permit you to conclude that they are probably equal.

Question 71

Which conclusion is not appropriate when using null hypothesis statistical testing (NHST)?

A) The two sample means probably came from two different populations.
B) The two samples probably came from the same population.
C) Retain the hypothesis that the two samples came from the same population.
D) all of the other alternatives are correct.

Question 72

This question requires careful thinking. The logic of null hypothesis statistical testing (NHST) involves assuming that

A) two populations have equal means and then using sample data to conclude that they are probably equal
B) two populations have unequal means and then using sample data to conclude that they are probably unequal
C) two populations have equal means and then using sample data to conclude that they are probably unequal
D) two populations have unequal means and then using sample data to conclude that they are probably equal.

Question 73

Null hypothesis statistical testing (NHST) allows an experimenter to conclude that the null hypothesis is

A) probably false
B) probably true
C) both of the descriptive alternatives are correct
D) neither of the descriptive alternatives is correct.

Question 74

The null hypothesis is

A) $\mu$ ₁ = $\mu$ ₂
B) $\mu$ ₁ $\neq$ $\mu$ ₂
C) $\mu$ ₁ $\neq$$\mu$ ₂
D) $\mu$ ₁ $\neq$ $\mu$ ₂
E) any of the alternative answers are correct.

Question 75

The null hypothesis is a statement about

A) populations
B) samples
C) both of the descriptive alternatives are correct
D) neither of the descriptive alternatives is correct.

Question 76

Which of the following is not an example of the null hypothesis?

A) $\mu$ ₁ $\neq$$\mu$ ₂.
B) $\mu$ ₁ $\neq$$\mu$ ₂..
C) $\mu$ ₁ $\neq$$\mu$ ₂
D) all of the other alternatives are correct..

Question 77

"There is no difference in the two populations"is a statement of

A) the null hypothesis
B) a one-tailed alternative hypothesis
C) a two-tailed alternative hypothesis

Question 78

"The difference between the two_________means is zero"is a statement of the null hypothesis.

A) sample
B) population
C) sample or population
D) none of the descriptive alternatives are correct.

Question 79

Determining whether there is a logical reason to pair two scores in a two-sample experiment is necessary in deciding whether

A) to use a one-tailed or two-tailed test
B) the design is a paired-samples or an independent-samples design
C) to use hypothesis testing or confidence intervals
D) all of the descriptive alternatives are correct.

Question 80

If you find that there is a logical reason to pair the scores from the two groups in a two-group experiment, you know whether

A) the design is a paired-samples or an independent-samples design
B) to use hypothesis testing or confidence intervals
C) to use a one-tailed or two-tailed test
D) all of the descriptive alternatives are correct.