Question 1

For a z-statistic of -1.34, the decision about the null hypothesis is ______.

Accepted Answer

A)   do not reject the null hypothesis (p > .05) 
B)   do not reject the null hypothesis (p 
C)   reject the null hypothesis (p > .05) 
D)   reject the null hypothesis (p < .05)  A

Question 2

A researcher calculates a value of 3.21 for a t-statistic. For df = 20 and alpha = .05 (two-tailed), which of the following is the MOST accurate?

Accepted Answer

A)   reject the null hypothesis
B)   p 
C)   p 
D)   do not reject the null hypothesis C

Question 3

If the value of the t-statistic calculated from a set of data ______ the critical value, you would say ______.

Accepted Answer

A)   exceeds; p 
B)   exceeds; p > .05
C)   does not exceed; p 
D)   does not exceed; p < .01 A

Question 4

A ______ symbol in the ______ hypothesis implies this hypothesis is ______.

Accepted Answer

A)   
B)   ≠; null; two-tailed
C)   >; null; non-directional
D)   ≠; alternative; directional

Question 5

Although their formulas are similar, one difference between the z-score (z) and the t-statistic (t) is that ______.

Accepted Answer

A)   only z-scores (not t-statistics)  are part of a theoretical distribution
B)   z-scores evaluate sample means whereas t-statistics evaluate individual scores
C)   the numerator of the t-statistic formula (not the z-score)  is the difference between a score and a mean
D)   the denominator of the t-statistic formula estimates the variability of sample means rather than individual scores

Question 6

You collect data from a sample of 150 people, and calculate a mean of 6.87 and a standard deviation of 3.69. What is the value for the standard error of the mean  ?

Accepted Answer

A)   .30
B)   1.86
C)   6.87
D)   21.83

Question 7

A researcher conducted an analysis that supported the research hypothesis that SJSU students spend less on textbooks than the average California college student. As a result of this finding, imagine you hypothesize that SJSU freshmen owe less on their credit cards than the average college freshman. To test this hypothesis, a group of college students are asked, "If you have your own credit card(s), how much do you currently owe on them?" The responses of some of the students in this class are summarized as: N = 25  = 834.53
S = 169.40
According to a recent study, the average college freshman owes $900 on their credit cards (Arano, 2006).
Based on your calculations, which of the following best represents the decision regarding the null hypothesis?

Accepted Answer

A)   do not reject H0 (p > .05) 
B)   do not reject H0 (p 
C)   reject H0 (p 
D)   reject H0 (p > .01)

Question 8

The statement µ > 3 is an example of a ______.

Accepted Answer

A)   directional (one-tailed)  null hypothesis
B)   directional (one-tailed)  alternative hypothesis
C)   non-directional (two-tailed)  null hypothesis
D)   non-directional (two-tailed)  alternative hypothesis

Question 9

Which of the following can be a negative number in testing the mean of a sample?

Accepted Answer

A)   the degrees of freedom
B)   the critical values
C)   alpha
D)   the standard error of the mean

Question 10

In testing the mean of a sample, the sample mean  is transformed into a ______ statistic in order to ______.

Accepted Answer

A)   z; decide whether to set alpha at .05 or .01
B)   t; determine the probability of a sample mean
C)   z; determine the critical values
D)   t; determine whether the distribution of sample means is normal

Question 11

Which of the following would be the most accurate way to report the following z-test?

Accepted Answer

A)   z = 2.55 
B)   z = 2.55  .05
C)   z = 2.55 
D)   z = 2.55  .01

Question 12

Looking at the ______ for a statistic like a t-statistic provides an indication of the sample size in a study.

Accepted Answer

A)   research hypothesis
B)   null hypothesis
C)   degrees of freedom
D)   alternative hypothesis

Question 13

A ______ symbol in the ______ hypothesis implies this hypothesis is ______.

Accepted Answer

A)   >; null; one-tailed
B)   ≠; null; directional
C)   ≠; alternative; non-directional
D)   =; alternative; one-tailed

Question 14

A researcher has calculated a z-statistic of 1.92. For a two-tailed test with alpha () = .05, which of the following is the most appropriate?

Accepted Answer

A)   do not reject the null (p 
B)   do not reject the null (p > .05) 
C)   reject the null (p 
D)   reject the null (p > .05)

Question 15

You calculate a value of 1.17 for the t-statistic and find falls in the region of non-rejection. As a result, the most appropriate conclusion is that you ______.

Accepted Answer

A)   do not reject the alternative hypothesis
B)   reject the null hypothesis
C)   reject the alternative hypothesis
D)   do not reject the null hypothesis

Question 16

You test the mean of a sample of 19 people and calculate a value of 2.14 for the t-statistic. For α = .05 (two-tailed), which of the following decisions is MOST appropriate?

Accepted Answer

A)   do not reject null (p > .01) 
B)   reject null (p > .05) 
C)   accept alternative (p > .05) 
D)   reject null (p < .05)

Question 17

Imagine that for a population of 200, the mean is 20.23 with a standard deviation of 5.12. What is the population standard error of the mean  ?

Accepted Answer

A)   .003
B)   .03
C)   .36
D)   .50

Question 18

A researcher draws a random sample of 25 people from a population and calculates the mean of their IQs. If she were to repeat this process of drawing samples and calculating means an infinite number of times, the sample means could be used to create ______.

Accepted Answer

A)   the sampling distribution of the mean
B)   critical values
C)   z-scores
D)   research hypotheses

Question 19

Which of the following is a correctly stated alternative hypothesis?

Accepted Answer

A)   H1: 1:   ≠ 3 
B)   H1: µ = 3 
C)   H1: α = .05 (two-tailed)  
D)   H1: µ ≠ 3" class="answers-bank-image d-inline" rel="preload" > ≠ 3
B)   H1: µ = 3
C)   H1: α = .05 (two-tailed) 
D)   H1: µ ≠ 3

Question 20

A study based on a sample of 13 participants calculates a value of 1.89 for the t-test for a single mean. For alpha (α) = .05 (two-tailed), which of the following is the correct way to present this analysis?

Accepted Answer

A)   t(12)  = 1.89, p 
B)   t(12)  = 1.89, p > .05
C)   t(13)  = 1.89, p 
D)   t(13)  = 1.89, p > .01

Exam 7: Testing One Sample Mean

For a z-statistic of -1.34, the decision about the null hypothesis is ______.

A researcher calculates a value of 3.21 for a t-statistic. For df = 20 and alpha = .05 (two-tailed) , which of the following is the MOST accurate?

If the value of the t-statistic calculated from a set of data the critical value, you would say .

A symbol in the hypothesis implies this hypothesis is __.

Although their formulas are similar, one difference between the z-score (z) and the t-statistic (t) is that ______.

You collect data from a sample of 150 people, and calculate a mean of 6.87 and a standard deviation of 3.69. What is the value for the standard error of the mean ?

The statement µ > 3 is an example of a ______.

Which of the following can be a negative number in testing the mean of a sample?

In testing the mean of a sample, the sample mean is transformed into a statistic in order to .