# Quiz 9: The Single-Sample T Test

Psychology

Q 1Q 1

The average salary for all 27 Arizona Diamondbacks in the 2012 baseball season was $2,653,029, with a standard deviation of $2,587,139.The population, all National League baseball players in 2012, earned an average salary of $3,213,479, with a standard deviation of $1,451,308.Does the average salary of the Diamondbacks players differ from that of all players in the National League? What statistical analysis is used to answer this question?
A) single-sample t test
B) z test
C) standard deviation analysis
D) dependent-samples t test

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Multiple Choice

B

Q 2Q 2

When the population mean but not the population standard deviation is known, which statistic is used to compare a sample to the population?
A)
B) z
C) F
D) t

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Multiple Choice

D

Q 3Q 3

It is known that the population mean on the math portion of the SAT is 500, with a standard deviation of 100.Assume that the average math SAT score for freshmen entering your college is 550, with a standard deviation of 110.Does the math performance of students entering your college differ from that of all individuals taking the SAT? What statistical analysis is used to answer this question?
A) single-sample t test
B) z test
C) standard deviation analysis
D) dependent-samples t test

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Multiple Choice

B

Q 4Q 4

As the sample size becomes smaller, the t distributions become:
A) narrower.
B) wider.
C) more reliable.
D) more accurate.

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Multiple Choice

Q 5Q 5

As the sample size becomes larger, the t distributions become:
A) narrower.
B) wider.
C) broader.
D) less accurate.

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Multiple Choice

Q 6Q 6

What is the correct formula for using the sample standard deviation to estimate the population standard deviation?
A)
B)
C)
D)

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Multiple Choice

Q 7Q 7

What is the correct formula for calculating the standard deviation of a sample when one is NOT trying to estimate the population standard deviation?
A)
B)
C)
D)

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Multiple Choice

Q 8Q 8

Why does one divide by N - 1 rather than by N when estimating a population standard deviation from the sample standard deviation?
A) Because the sample standard deviation is likely to be an imprecise estimate, we allow the error of the estimate (the standard deviation) to be larger by dividing the sum of squares by a smaller number.
B) The sample standard deviation is a superior estimate of the variability in the population than is the population standard deviation.
C) We typically have to throw out at least one data point in any given study, so the N - 1 allows us to account for that.
D) Because the population is always smaller than the sample, we must divide by a smaller number.

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Multiple Choice

Q 9Q 9

The following data were collected from a veterinarian's office over the course of a day to assess the average weight of dogs (in pounds): 10, 5, 17, 22, 50, 32, 38, and 29.What is the standard deviation for these data, first without the correction and then with the correction used when estimating a population?
A) 13.00; 13.90
B) 13.90; 13.00
C) 13.95; 14.91
D) 14.91; 13.95

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Multiple Choice

Q 10Q 10

The symbol representing a standard deviation calculated by using a sample to estimate the population standard deviation is:
A) sd.
B) .
C) s.
D) SD.

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Multiple Choice

Q 11Q 11

As the sample size becomes larger, the t distributions look ________ the z distribution.
A) less like
B) more like
C) different from
D) taller than

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Q 12Q 12

The symbol s is a _____ letter that describes a _____ statistic.
A) Latin; sample
B) Greek; sample
C) Latin; population
D) Greek; population

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Multiple Choice

Q 13Q 13

A researcher collects 25 data points that yield a mean of 8.164 and a standard deviation (based on N - 1) of 2.237.What is the standard error for the distribution of means?
A) 0.089.
B) 0.200
C) 0.447
D) 0.614

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Multiple Choice

Q 14Q 14

If the standard deviation for a population, as estimated from a sample, is s = 6.47, then the standard error for a sample size of N = 20 is s

_{M}=: A) 0.32. B) 1.45. C) 2.09. D) 2.29.Free

Multiple Choice

Q 15Q 15

The standard deviation of a distribution of scores in a sample is known as _____, while the standard deviation of a distribution of means is referred to as _____.
A) s

_{M}; s B) s; C) s; s_{M}D) _{M}; Free

Multiple Choice

Q 16Q 16

If the standard deviation for a population, as estimated from a sample, is s = 3.8, then the standard error for a sample size of N = 16 is s

_{M}=: A) 0.24. B) 0.90. C) 0.95. D) 1.40.Free

Multiple Choice

Q 17Q 17

A t statistic is _______ as a z statistic, making it _______.
A) not as extreme; less conservative
B) not as extreme; more conservative
C) more extreme; less conservative
D) more extreme; more conservative

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Multiple Choice

Q 18Q 18

A researcher collects 25 data points that yield a mean of 8.164 and a standard deviation (based on N - 1) of 2.237.If the researcher is comparing the sample to a population mean of 9.2, what is the value of the test statistic?
A) 0.447
B) -1.036
C) -2.316
D) -2.339

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Q 20Q 20

The difference between the denominator of the z statistic and that of the single-sample t statistic is that in a:
A) z statistic we divide by the actual population standard error (s

_{M}), but in a t statistic we divide by the estimated standard error (_{M}). B) z statistic we divide by the actual population standard error (_{M}), but in a t statistic we divide by the estimated standard error (s_{M}). C) t statistic we divide by the actual population standard error (s_{M}), but in a z statistic we divide by the estimated standard error (_{M}). D) t statistic we divide by the actual population standard error (_{M}), but in a z statistic we divide by the estimated standard error (s_{M}).Free

Multiple Choice

Q 21Q 21

The numerator (top portion) of the ratio for calculating all t statistics contains:
A) a difference between means.
B) a variance estimate.
C) the degrees of freedom.
D) the sample mean.

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Multiple Choice

Q 22Q 22

The t statistic indicates the:
A) number of standard deviations an individual score is from the sample mean.
B) number of standard deviations a sample is from the population mean.
C) distance of two sample means from a single population mean.
D) distance of a sample mean from the population mean in terms of estimated standard error.

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Multiple Choice

Q 23Q 23

When scientists call a hypothesis test conservative, they mean that it:
A) is difficult to reject the null hypothesis (i.e., the status quo).
B) leads to results that Republicans will find favorable.
C) is very easy to reject the null hypothesis (i.e., the status quo).
D) leads to results that Democrats will find favorable.

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Multiple Choice

Q 24Q 24

A newspaper article reported that the typical American family spent an average of $81 for Halloween candy and costumes last year.A sample of N = 16 families this year reported spending a mean of M = $85, with s = $20.What statistical test would be used to determine whether these data indicate a significant change in holiday spending?
A) single-sample t test
B) z test
C) effect size test
D) paired-samples t test

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Multiple Choice

Q 25Q 25

Many companies that manufacture lightbulbs advertise their 60-watt bulbs as having an average life of 1000 hours.A cynical consumer bought 30 bulbs and burned them until they failed.He found that they burned for an average of M = 1233, with a standard deviation of s = 232.06.What statistical test would this consumer use to determine whether the average burn time of lightbulbs differs significantly from that advertised?
A) single-sample t test
B) z test
C) standard deviation analysis
D) dependent-samples t test

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Multiple Choice

Q 26Q 26

The single-sample t test compares a sample mean to a population mean when:
A) the sample standard deviation is unknown.
B) no comparison can be made based on the variability in either group.
C) the population standard deviation is unknown.
D) a within-groups design is employed.

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Multiple Choice

Q 27Q 27

The formula for the degrees of freedom for the single-sample t test is:
A) N.
B) df

_{X}+ df_{Y}_{.}C) N - 1. D) (N - 1)(N - 1).Free

Multiple Choice

Q 28Q 28

With very few degrees of freedom, the test statistic:
A) becomes more reliable.
B) should be a z test rather than a t test.
C) needs to be more extreme to reject the null hypothesis.
D) needs to be less extreme to reject the null hypothesis.

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Multiple Choice

Q 29Q 29

A single-sample t test is conducted on a sample of 26 people who were selected from a large population estimated at 2500 people.The critical cutoff for a two-tailed test at a p level of 0.05 would be:
A) -1.706 and 1.706.
B) -1.708 and 1.708.
C) -2.056 and 2.056.
D) -2.060 and 2.060.

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Multiple Choice

Q 30Q 30

At a sample size of infinity, the t distribution:
A) is unreliable.
B) has a standard deviation of 0.
C) is identical to the z distribution.
D) has a standard deviation of 0.50.

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Multiple Choice

Q 31Q 31

The first step in conducting the single-sample t test includes:
A) identifying a Type I error.
B) identifying a Type II error.
C) checking that assumptions have been met.
D) stating the null hypothesis.

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Multiple Choice

Q 32Q 32

A negatively skewed distribution would most likely violate which assumption?
A) normality
B) dependent variable is scale
C) random selection
D) random assignment

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Q 33Q 33

H

_{0}: _{1}= _{2}is used to represent the: A) confidence interval. B) research hypothesis. C) null hypothesis. D) standard error.Free

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Q 34Q 34

H

_{1}: _{1} _{2}is used to represent the: A) confidence interval. B) research hypothesis. C) null hypothesis. D) standard error.Free

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Q 35Q 35

The second step in conducting the single-sample t test includes:
A) identifying a Type I error.
B) identifying a Type II error.
C) checking that assumptions have been met.
D) stating the null hypothesis.

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Multiple Choice

Q 36Q 36

The second step in conducting the single-sample t test involves _____ and _____.
A) identifying a Type I error; checking that assumptions have been met
B) identifying a Type II error; stating the null hypothesis
C) stating the null hypothesis; stating the research hypothesis
D) stating the null hypothesis; identifying effect size

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Multiple Choice

Q 37Q 37

The third step in conducting the single-sample t test is:
A) identifying a Type I error.
B) stating the null hypothesis.
C) stating the research hypothesis.
D) determining the characteristics of the comparison distribution.

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Multiple Choice

Q 38Q 38

The fourth step in conducting the single-sample t test is:
A) identifying a Type I error.
B) determining the critical values or cutoffs.
C) calculating the test statistic.
D) determining the characteristics of the comparison distribution.

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Multiple Choice

Q 39Q 39

The fifth step in conducting the single-sample t test is:
A) identifying a Type I error.
B) determining the critical values or cutoffs.
C) calculating the test statistic.
D) determining the characteristics of the comparison distribution.

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Multiple Choice

Q 40Q 40

Based on the statistical results provided, which would lead us to reject the null hypothesis?
A) t(5) = 3.2, p = 0.06
B) t(5) = 3.2, p = 0.10
C) t(5) = 3.2, p < 0.05
D) t(5) = 3.2, p > 0.05

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Multiple Choice

Q 41Q 41

Based on the statistical results provided, which would lead us to fail to reject the null hypothesis?
A) t(5) = 3.2, p = 0.04
B) t(5) = 3.2, p = 0.01
C) t(5) = 3.2, p < 0.05
D) t(5) = 3.2, p > 0.05

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Multiple Choice

Q 42Q 42

The final step in conducting the single-sample t test is:
A) making a decision.
B) calculating the test statistic.
C) determining the critical values.
D) identify the characteristics of the comparison distribution.

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Multiple Choice

Q 43Q 43

Which report of statistical results is in appropriate APA format?
A) t(5) = 1.2, fail to reject null
B) t = 1.2, df = 5, reject null
C) t(5) = 1.2, p > 0.05
D) t = 1.2, df = 5, p > 0.05

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Multiple Choice

Q 44Q 44

For the single-sample t test, the confidence interval is centered around the:
A) sample mean.
B) population mean.
C) difference between the sample and population means.
D) standard error of the distribution of means.

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Multiple Choice

Q 45Q 45

A researcher collects 25 data points that yield a mean of 8.164 and a standard deviation (based on N - 1) of 2.237.If the researcher is comparing the sample to a population mean of 9.2, what is the 95 percent confidence interval?
A) [6.92, 9.41]
B) [7.24, 9.09]
C) [7.75, 8.58]
D) [7.85, 10.48]

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Multiple Choice

Q 46Q 46

Imagine the average time to complete a 4-year bachelor degree is actually 4.7 years based on national data.You collect data on the 68 psychology students who started school during the same semester as you, finding an average time to complete at 4.3 years with a standard deviation of 0.6 years.What is your 95 percent confidence interval?
A) [4.23, 4.37]
B) [3.85, 4.15]
C) [4.10, 5.30]
D) [4.15, 4.45]

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Multiple Choice

Q 47Q 47

The correct formula for the upper bound of a confidence interval for a single-sample t test is:
A) t(s

_{M}) + M_{sample}. B) -t(s_{M}) - M_{sample}. C) t(s_{M}) - M_{sample}. D) -t(s_{M}) +M_{sample}.Free

Multiple Choice

Q 48Q 48

The correct formula for the lower bound of a confidence interval for a single-sample t test is:
A) t(s

_{M}) + M_{sample}. B) -t(s_{M}) - M_{sample}. C) t(s_{M}) - M_{sample}. D) -t(s_{M}) +M_{sample}.Free

Multiple Choice

Q 49Q 49

A team of researchers conducted a single-sample t test and found that the 95 percent confidence interval around their sample mean includes the value of the population mean.Based on this, they should conclude that:
A) the null hypothesis should be rejected.
B) their data are insufficient to assess the validity of the null hypothesis.
C) they failed to find a significant difference between the sample and population means.
D) the research hypothesis is supported.

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Multiple Choice

Q 50Q 50

The correct formula for effect size using Cohen's d for a single-sample t test is:
A) (M - )/s + .
B) (M - )/s.
C) (X - )/s.
D) ( - )/s.

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Multiple Choice

Q 51Q 51

A researcher collects 25 data points that yield a mean of 8.164 and a standard deviation (based on N - 1) of 2.237.If the researcher is comparing the sample to a population mean of 9.2 using a single-sample t test, what would be the effect size?
A) -0.60
B) -0.46
C) 0.46
D) 0.68

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Multiple Choice

Q 52Q 52

Imagine the average time to complete a 4-year bachelor degree is actually 4.7 years based on national data.You collect data on the 68 psychology students who started school during the same semester as you, finding an average time to complete at 4.3 years with a standard deviation of 0.6 years.What would be the effect size associated with a single-sample t test?
A) -5.48
B) -0.67
C) 0.20
D) 0.82

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Multiple Choice

Q 53Q 53

When performing a single-sample t test, an effect size of 0.80 would be interpreted as a _____ effect.
A) small
B) medium
C) large
D) negligible

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Q 54Q 54

When performing a single-sample t test, an effect size of 0.50 would be interpreted as a _____ effect.
A) small
B) medium
C) large
D) negligible

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Q 55Q 55

When performing a single-sample t test, an effect size of 0.20 would be interpreted as a _____ effect.
A) small
B) medium
C) large
D) negligible

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Q 56Q 56

A researcher conducts a single-sample t test and finds statistical significance at the 0.01 level.The effect size is then calculated and found to be 0.04.What might be concluded about the findings?
A) The findings are statistically significant, but the effect size indicates that they may not be practically significant.A very large sample may have been studied, driving up the test statistic value.
B) The findings seem flawed because without a substantial effect size, it is not possible to find statistical significance.
C) The findings are both statistically and practically significant in this case, as the effect size indicates a medium effect, and the 0.01 level of significance is rather impressive.
D) These findings are exciting because statistical significance was found with a very small effect, indicating that the results are real and the chance of a Type I error are low.

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Multiple Choice

Q 57Q 57

Two types of graphs that make it easy to see the distribution of two variables side-by-side are the:
A) histogram and dot plot.
B) stem-and-leaf plot and dot plot.
C) histogram and box plot.
D) stem-and-leaf plot and histogram.

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Multiple Choice

Q 58Q 58

Use the following to answer questions
This figure represents the distribution of the percent of state residents living in a metropolitan area for all 50 U.S.states and Washington D.C.
-(Figure: Percent Metropolitan) The plot in the figure is a:
A) histogram.
B) stem-and-leaf plot.
C) dot plot.
D) box plot.

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Q 59Q 59

Use the following to answer questions
This figure represents the distribution of the percent of state residents living in a metropolitan area for all 50 U.S.states and Washington D.C.
-(Figure: Percent Metropolitan) The figure indicates that:
A) most states have greater than 60 percent of their population living in metropolitan areas.
B) on average, 60 percent of all states' populations live in a metropolitan area.
C) the population of most states is concentrated in rural areas.
D) few states have larger urban centers.

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Multiple Choice

Q 60Q 60

The t test is a parametric statistical test that allows one to generalize what was learned about one sample to a larger population.

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True False

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True False

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True False

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True False

Q 64Q 64

The standard deviation of the population is used to estimate the standard deviation of the sample.

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True False

Q 65Q 65

The standard deviation of the sample is used to estimate the standard deviation of the population.

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True False

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True False

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True False

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True False

Q 69Q 69

A sample of 20 with a standard deviation of 92.41 results in a standard error calculated as 20.66.

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True False

Q 70Q 70

Standard error is always smaller than the standard deviation because a distribution of means is less variable than that of scores.

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True False

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True False

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True False

Q 73Q 73

A sample of 20 with a standard deviation of 92.41 results in a standard error calculated as 22.88.

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True False

Q 74Q 74

The t statistic indicates the distance of a sample mean from a population mean in terms of estimated standard error.

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True False

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True False

Q 76Q 76

The single-sample t test compares the mean of a sample to a population for which the mean and standard deviation is known.

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True False

Q 77Q 77

The single-sample t test compares the mean of a sample to a population for which the mean but not the standard deviation is known.

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True False

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True False

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True False

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True False

Q 81Q 81

A t distribution with 2 degrees of freedom has fewer extreme scores than a t distribution with 30 degrees of freedom.

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True False

Q 82Q 82

The more observations made, the more confident one can be in the estimate of the population.

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True False

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True False

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True False

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True False

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True False

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True False

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True False

Q 89Q 89

If a t statistic is calculated and found to be negative, then there has been an error in its calculation.

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True False

Q 90Q 90

If a t statistic is calculated and found to be positive, then something has been done right in its calculation.

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True False

Q 91Q 91

The appropriate APA format for the presentation of t test results appears as: t = 3.13, df = 19, p < 0.05.

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True False

Q 92Q 92

The appropriate APA format for the presentation of t test results appears as: t(19) = 3.13, p < 0.05.

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True False

Q 93Q 93

When computing the confidence interval for a t test, the cutoffs for the 95 percent interval are always the same.

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True False

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True False

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True False

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True False

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True False

Q 98Q 98

Dot plots display the range of sample scores along the x-axis and a dot for each data point in the sample above the appropriate value.

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True False

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True False

Q 100Q 100

Why does correcting the standard deviation to account for error in a t test make a much bigger difference for small samples than it does for larger ones?
A) We subtract 1 from the sample size, which removes a greater proportion of the total and corrects to a greater degree for smaller sample sizes compared to larger ones.
B) Small samples are biased.
C) We add 1 to the sample size, which removes a greater proportion of the total for smaller sample sizes compared to larger ones.
D) Large samples are biased.

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Multiple Choice

Q 101Q 101

Standard error is used in the calculation of both the z and t statistic, with the difference that:
A) t statistics require fewer numeric calculations than z statistics.
B) the standard error for the t statistic is estimated using the sample standard deviation.
C) the z statistic is based on known properties of the sample being studied.
D) the population standard deviation is the basis of standard error in the t test.

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Q 102Q 102

Is it necessary to correct for error when calculating the standard error for a t test? Explain your answer.
A) Yes; we are estimating the standard deviation of the population.
B) Yes; we are estimating both the mean and standard deviation of the population.
C) No; we already corrected the standard deviation and are now reflecting the size of the sample.
D) No; we are estimating both the mean and standard deviation of the population.

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Multiple Choice

Q 103Q 103

The t statistic is more _____ than the z statistic because one is less likely to observe an extreme t statistic.
A) conservative
B) liberal
C) extreme
D) representative

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Q 104Q 104

In order to conduct a single-sample t test, one needs to know:
A) the population mean and standard deviation, and the standard error of the sample.
B) all properties of the sample and the population.
C) the mean of the sample and all properties of the population.
D) the population mean and the properties of the sample.

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Multiple Choice

Q 105Q 105

"Degrees of freedom" refers to what on a t table for a single-sample t test?
A) number of restrictions enforced on people in the sample
B) total sample size of the distribution, N
C) number of scores that are free to vary in estimating population parameters, N - 1
D) amount of variance in the t distribution

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Multiple Choice

Q 106Q 106

According to the Consumer Action group, the average credit card interest rate in 2010 was 12.83 percent (based on a sample of 39 cards).A researcher wanted to know if college students at her institution have different interest rates compared to this national statistic.If conducting a single-sample t test, which statement would serve as her research hypothesis?
A) The national interest rate is higher than that of college students, on average.
B) College students have different interest rates on average compared to the nation.
C) The national interest rate is not different from that of college students.
D) College students have the same interest rate as the nation.

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Multiple Choice

Q 107Q 107

Which report of statistical results is in appropriate APA format?
A) t(24) = 4.1, fail to reject null
B) t = 4.1, df = 24, reject null
C) t(24) = 4.1, p < 0.05
D) t = 4.1, df = 24, p < 0.05

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Q 108Q 108

The confidence interval provides _____ information than the hypothesis test.
A) less
B) the same
C) more
D) the opposite

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Q 109Q 109

Assume that the national credit card interest rate is 12.83 percent.A study of 81 college students finds that their average interest rate is 15 percent with a standard deviation of 8.7 percent.What is the 95 percent confidence interval for this single-sample t test?
A) [10.54, 19.54]
B) [11.64, 16.36]
C) [12.99, 15.01]
D) [13.08, 16.92]

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Q 110Q 110

Assume that the national credit card interest rate is 12.83 percent.A study of 62 college students finds that their average interest rate is 14 percent with a standard deviation of 9.3 percent.What is the 95 percent confidence interval for this single-sample t test?
A) [10.47, 15.19]
B) [11.64, 16.36]
C) [12.99, 15.01]
D) [6.94, 11.66]

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Multiple Choice

Q 111Q 111

The correct formula for Cohen's d for a single-sample t test is:
A) (X - M)/N.
B) (X - M)/(N - 1).
C) (M - )/s.
D) (M - )/(s - 1).

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Multiple Choice

Q 112Q 112

A dot plot graphs all the data in a sample, with the range of scores along the _____ and a dot for each data point above the corresponding value.
A) x-axis
B) y-axis
C) variance
D) line of best fit

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Multiple Choice

Q 113Q 113

When there is uncertainty about the parameters of a population of interest, a t distribution is used instead of a z distribution.Is the t distribution wider or thinner than the z distribution and why?
A) The t distribution is wider because we are less certain of the findings compared to the z distribution.
B) The t distribution is thinner because we are less certain of the findings compared to the z distribution.
C) They produce the same curve because they both use the population mean.
D) They produce the same curve because they both use the standard deviation of the population.

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Multiple Choice

Q 114Q 114

A researcher is comparing two groups.The population mean from which the samples come is known, but not the population standard deviation.Which test should be used?
A) either the t or z test
B) neither the t or z test because more information is needed
C) z test because the population parameters are known
D) t test because standard deviation for the population must be estimated

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Multiple Choice

Q 115Q 115

Which equation is the correct formula for the t statistic for a distribution of means?
A) (X -

_{M})/s B) (_{M}- M)/ C) (M - _{M})/s D) (M -_{M})/s_{M}Free

Multiple Choice

Q 116Q 116

The _____ indicates the distance of a sample mean from a population mean in terms of the standard error.
A) paired-sample t test
B) z statistic
C) t statistic
D) standard deviation

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Q 117Q 117

The symbol df stands for:
A) distance from mean.
B) degrees of freedom.
C) distance from mode.
D) degrees of f estimation.

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Q 119Q 119

What is one benefit of increasing the sample size when using t distributions?
A) Larger sample sizes cost less when running the experiment than small samples.
B) Larger sample sizes reflect the parameters of the population more closely.
C) Larger sample sizes make better graphs.
D) Larger sample sizes distance themselves from z distributions.

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Q 120Q 120

Critical t values _____ as the degrees of freedom _____.
A) decrease; increase
B) increase; increase
C) decrease; decrease
D) decrease; approach 0

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Q 121Q 121

Griffin is looking through a statistics text for a z table, but he can find only a t table in the index.What tip would best help him find the information he needs?
A) Add 1 to all the scores in the t table to find the corresponding z statistic.
B) Go to the library to look up the z table.
C) Use a different distribution instead of a z distribution.
D) Use the sample size of infinity listed in the t table because it is equal to the z table.

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Multiple Choice

Q 122Q 122

An effect size of 0.53 was calculated on data after performing a hypothesis test with a single-sample t statistic in which the null hypothesis was rejected.What can be concluded about the results based on this information?
A) The research hypothesis is supported, but the effect size is small.
B) The sample data are significantly different from what was expected based on the population, with the sample mean 0.53 standard deviations greater than the population mean.
C) The population mean is 0.53 standard error units greater than the sample mean, and the results are significant.
D) The effect size is medium, which means there is a medium risk that a Type I error has occurred.

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Multiple Choice

Q 123Q 123

When the population mean falls in our confidence interval, we conclude that the sample:
A) comes from a different population.
B) comes from the same population.
C) is not representative of the population.
D) was obtained in error.

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Multiple Choice

Q 124Q 124

A dot plot allows us to _____, while a stem-and-leaf plot does not.
A) view the overall shape of the sample
B) view all individual data points
C) include more than one sample
D) display a range of scores along the y-axis

Free

Multiple Choice