Question 1

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)  .16 
B)  .30 
C)  3.69 
D)  12.24

Question 2

The modality, symmetry, and variability of the sampling distribution of the mean are defined by a statistical principle known as ______.

Accepted Answer

A)  random sampling 
B)  ratio scale of measurement 
C)  standard error of the mean 
D)  central limit theorem

Question 3

Use this information below to answer questions 116-120.
As alcohol-related problems are a concern on college campuses, research has been conducted regarding students' perceptions of drinking behavior. For example, one study found students have misconceptions regarding what is considered excessive ("binge") drinking (White et al, 2004). Imagine you believe students' definition of binge drinking will differ from the government's definition. More specifically, you hypothesize students will overestimate the number of drinks needed to be consumed to be defined as binge drinking. To test this hypothesis, a group of college students are asked, "How many drinks in a row must a man drink in order to define it as "binge drinking?" The responses of some of the students in this class are summarized as:
N = 16  = 7.94
s = 4.63
-For α = .05 (two-tailed), which of the following is an appropriate critical value?

Accepted Answer

A)  1.746 
B)  2.042 
C)  2.120 
D)  2.131

Question 4

Standard deviation measures the ______ for a variable, standard error represents the ______ calculated from samples.

Accepted Answer

A)  variability of statistics; variability of scores 
B)  variability of scores; variability of statistics 
C)  variability of scores; error of scores 
D)  variability of statistics; error of scores

Question 5

If I wanted to measure the variability of ______ , I would calculate ______.

Accepted Answer

A)  individual scores (Xs); the standard error of the mean  
B)  sample means  ; the standard error of the mean
 
C)  sample means  ; the standard deviation (s) 
D)  individual scores (Xs); the sample mean

Question 6

The ______ of the sampling distribution of the mean may be represented by ______.

Accepted Answer

A)  symmetry; 0 
B)  variability; 1 
C)  modality; s 
D)  variability;

Question 7

A researcher calculates a mean from a sample of 21 people. In analyzing her data, she states the following hypotheses: H0: μ = 16 and H1: μ ≠ 16. For α = .05, which is an appropriate critical value?

Accepted Answer

A)  1.725 
B)  2.086 
C)  2.093 
D)  2.131

Question 8

A researcher tests the mean of a sample of 22 people and calculates a value of 1.81 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  .05) 
C)  reject null (p  .05)

Question 9

A statistic with less than a .01 probability is not simply statistically "significant", but should be referred to as "highly significant".

Accepted Answer

A) True 
 B)False

Question 10

Use this information below to answer questions 116-120.
As alcohol-related problems are a concern on college campuses, research has been conducted regarding students' perceptions of drinking behavior. For example, one study found students have misconceptions regarding what is considered excessive ("binge") drinking (White et al, 2004). Imagine you believe students' definition of binge drinking will differ from the government's definition. More specifically, you hypothesize students will overestimate the number of drinks needed to be consumed to be defined as binge drinking. To test this hypothesis, a group of college students are asked, "How many drinks in a row must a man drink in order to define it as "binge drinking?" The responses of some of the students in this class are summarized as:
N = 16  = 7.94
s = 4.63
-Based on your calculations, which of the following represents your decision regarding the null hypothesis?

Accepted Answer

A)  Do not reject H0 (p > .05) 
B)  Reject H0 (p 0 (p 0 (p > .01)

Question 11

I draw a random sample from the population and calculate the mean of this sample  . If I were to do this an infinite number of times, I could create ______.

Accepted Answer

A)  the sampling distribution of the mean 
B)  the null hypothesis 
C)  the standard normal distribution (normal curve) 
D)  the standard deviation

Question 12

Another researcher calculates a mean from a sample of 25 people. For α = .05, if he states the hypotheses as H0: μ = 100 and H1: μ < 100, which of the following is an appropriate critical value?

Accepted Answer

A)  1.714 
B)  1.711 
C)  1.708 
D)  2.060

Question 13

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

Accepted Answer

A)  sample means; individual scores for a variable 
B)  individual scores for a variable; sample means 
C)  scores; probabilities 
D)  normal distributions; skewed distributions

Question 14

What is the sufficient sample size to use for the central limit theorem?

Accepted Answer

A)  at least 25 
B)  at least 26 
C)  at least 30 
D)  at least 31

Question 15

Which of the following is a similarity of the t-distribution and the standard normal distribution?

Accepted Answer

A)  There is only one distribution for each. 
B)  Both distributions are symmetrical. 
C)  Both distributions are asymmetrical. 
D)  Both distributions are a function of the sample size.

Question 16

In testing the mean of a sample, calculating a positive value of the t-statistic (t) necessarily implies ______.

Accepted Answer

A)  the research hypothesis has been supported 
B)  you have done your calculations correctly (without making a mistake) 
C)  the value of the t-statistic falls in the region of rejection 
D)  the sample mean is greater than the hypothesized population mean

Question 17

A study based on a sample of 30 participants calculates a value of 2.56 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(29) = 2.56, p > .05 B) t(29) = 2.56, p > .01 C) t(29) = 2.56, p < .05 D) t(29) = 2.56, p < .01

Question 18

Using the following information, calculate the z-statistic for the z-test for one mean.  = 31.75 μ = 25.67  = 2.45

Accepted Answer

A)  2.48 
B)  -2.48 
C)  .10 
D)  -.10

Question 19

A researcher calculates a mean from a sample of 15 people. In analyzing her data, she states the following hypotheses: H0: μ = 25 and H1: μ ≠ 25. If α = .05, which of the following is an appropriate critical value?

Accepted Answer

A)  1.709 
B)  1.753 
C)  2.060 
D)  2.145

Question 20

In reporting the result of a statistical analysis, a researcher reports that "p < .01". This necessarily implies that ______.

Accepted Answer

A)  the null hypothesis was not rejected 
B)  the research hypothesis was not supported 
C)  p  .05

Exam 7: Testing One Sample Mean

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 modality, symmetry, and variability of the sampling distribution of the mean are defined by a statistical principle known as ______.

Standard deviation measures the for a variable, standard error represents the calculated from samples.

If I wanted to measure the variability of , I would calculate .

The of the sampling distribution of the mean may be represented by .

A researcher calculates a mean from a sample of 21 people. In analyzing her data, she states the following hypotheses: H₀: μ = 16 and H₁: μ ≠ 16. For α = .05, which is an appropriate critical value?

A researcher tests the mean of a sample of 22 people and calculates a value of 1.81 for the t-statistic. For α = .05 (two-tailed) , which of the following decisions is MOST appropriate?

A statistic with less than a .01 probability is not simply statistically "significant", but should be referred to as "highly significant".

I draw a random sample from the population and calculate the mean of this sample . If I were to do this an infinite number of times, I could create ______.

Another researcher calculates a mean from a sample of 25 people. For α = .05, if he states the hypotheses as H₀: μ = 100 and H₁: μ < 100, which of the following is an appropriate critical value?

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

What is the sufficient sample size to use for the central limit theorem?

Which of the following is a similarity of the t-distribution and the standard normal distribution?

In testing the mean of a sample, calculating a positive value of the t-statistic (t) necessarily implies ______.

A study based on a sample of 30 participants calculates a value of 2.56 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?

Using the following information, calculate the z-statistic for the z-test for one mean. = 31.75 μ = 25.67 = 2.45

A researcher calculates a mean from a sample of 15 people. In analyzing her data, she states the following hypotheses: H₀: μ = 25 and H₁: μ ≠ 25. If α = .05, which of the following is an appropriate critical value?

In reporting the result of a statistical analysis, a researcher reports that "p < .01". This necessarily implies that ______.