Question 1

One-sample t test procedures are for use on subjects that are _______.

Accepted Answer

A) independent 
B) the same or similar 
C) binomial 
D) None of the above 
A) independent 
B) the same or similar 
C) binomial 
D) None of the above

Question 2

Suppose you are interested in determining if the average amount of money that students spend on food at your university per day is greater than $30.You randomly choose 25 students from your campus and calculate that the mean amount of money spent per day is $18.01 with a standard deviation of $2.22.What is the standard error of the mean?

Accepted Answer

A) .44 
B) 0 
C) 18.01 
D) None of the above 
A) .44 
B) 0 
C) 18.01 
D) None of the above

Question 3

Do students tend to improve their SAT Mathematics (SAT-M)scores the second time they take the test? A random sample of four students who took the test twice received the following scores.   Assume that the change in SAT-M score (second score - first score)for the population of all students taking the test twice is Normally distributed.What is a 90% confidence interval for F1F1F1S1F1F1F10,the mean change in SAT-M score?

Accepted Answer

A) (-8.24,58.24) 
B) (-18.08,68.08) 
C) (-22.56,72.56) 
D) (-39.31,89.31) 
A) (-8.24,58.24) 
B) (-18.08,68.08) 
C) (-22.56,72.56) 
D) (-39.31,89.31)

Question 4

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students.   What is the standard error of the mean?

Accepted Answer

A) 29.4 
B) 8.86 
C) 11.4 
D) None of the above 
A) 29.4 
B) 8.86 
C) 11.4 
D) None of the above

Question 5

A study was done to determine whether there is a difference in the amount of time (in hours)that graduate students versus undergraduate students spend on the Internet per day.The results of the analysis are shown below.   The alternative hypothesis was _____.

Accepted Answer

A) one sided 
B) two sided 
A) one sided 
B) two sided

Question 6

Matched-pairs t procedures are for use on subjects that are _______.

Accepted Answer

A) independent 
B) the same or similar 
C) Normal 
D) None of the above 
A) independent 
B) the same or similar 
C) Normal 
D) None of the above

Question 7

The t procedures will be exact when the sample size is very large.

Accepted Answer

A) True 
 B)False

Question 8

When the sample size is very large,the corresponding t distribution is very close to the normal distribution.

Accepted Answer

A) True 
 B)False

Question 9

When calculating a one-sample t confidence interval,which level of confidence will give the largest interval?

Accepted Answer

A) 80% 
B) 90% 
C) 95% 
D) 100% 
A) 80% 
B) 90% 
C) 95% 
D) 100%

Question 10

A study was to be undertaken to determine if a particular training program would improve physical fitness.An SRS of 31 university students was selected to be enrolled in the fitness program.One important measure of fitness is maximum oxygen uptake.Measurements of oxygen uptake in untrained individuals are known to follow a Normal distribution with a mean of F1F1F1S1F1F1F10 = 45 mL/kg/min.The researchers wished to determine if there was evidence that their sample of students differed from the general population of untrained subjects.The measurements made on the subjects coming into this study produced a mean of   = 47.4 mL/kg/min with a standard deviation of s = 5.3 mL/kg/min.Suppose the 98% confidence interval were determined to be (45.2,49.6)an interval.If the level of confidence were changed to 95%,what would happen to the confidence interval and the P-value?

Accepted Answer

A) The confidence interval would become longer and the P-value would decrease. 
B) The confidence interval would become shorter and the P-value would increase. 
C) The confidence interval would not change and the P-value also would not change. 
D) The confidence interval would become shorter and the P-value would decrease. 
E) The confidence interval would become shorter but the P-value would not change. 
A) The confidence interval would become longer and the P-value would decrease. 
B) The confidence interval would become shorter and the P-value would increase. 
C) The confidence interval would not change and the P-value also would not change. 
D) The confidence interval would become shorter and the P-value would decrease. 
E) The confidence interval would become shorter but the P-value would not change.

Question 11

The P-values for a one-sided hypothesis test are generally _____ the P-values for the two-sided hypothesis test on the same data.

Accepted Answer

A) smaller than 
B) larger than 
C) the same as 
A) smaller than 
B) larger than 
C) the same as

Question 12

Suppose you are interested in determining if the average amount of money that students spend on food at your university per day is greater than $30.You randomly choose 25 students from your campus and calculate that the mean amount of money spent per day is $18.01 with a standard deviation of $2.22.What are the degrees of freedom for the one-sample t statistic?

Accepted Answer

A) 26 
B) 25 
C) 24 
D) 23 
A) 26 
B) 25 
C) 24 
D) 23

Question 13

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students.   What is the value of the t statistic after removing the second observation (value = 100)?

Accepted Answer

A) 6.65 
B) 1.43 
C) 0 
D) None of the above 
A) 6.65 
B) 1.43 
C) 0 
D) None of the above

Question 14

A simple random sample of 100 postal employees is used to test if the average time postal employees have worked for the postal service has changed from the value of 7.5 years recorded 20 years ago.The sample mean was   = 7 years with a standard deviation of s = 2 years.Assume the distribution of the time the employees have worked for the postal service is approximately Normal.The hypotheses being tested are H0: F1F1F1S1F1F1F10 = 7.5 versus Ha: F1F1F1S1F1F1F10 F1F1F1S1F1F1F10 7.5.A one-sample t test will be used.What is a 95% confidence interval for F1F1F1S1F1F1F10,the population mean time the postal service employees have spent with the postal service?

Accepted Answer

A) 7 ± 2 
B) 7 ± 1.984 
C) 7 ± 0.4 
D) 7 ± 0.2 
A) 7 ± 2 
B) 7 ± 1.984 
C) 7 ± 0.4 
D) 7 ± 0.2

Question 15

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students.   Would a t procedure be appropriate for these data?

Accepted Answer

A) Yes,the necessary assumptions have been met for a t procedure 
B) No,the necessary assumptions have not been met for a t procedure 
A) Yes,the necessary assumptions have been met for a t procedure 
B) No,the necessary assumptions have not been met for a t procedure

Question 16

Let n1 represent the sample size of the first group and n2 the sample size of the second group.A t procedure can be used when n1 + n2 is ____ as long as there are no outliers.

Accepted Answer

A) at least 2 and less than 5 
B) at least 5 and less than 10 
C) at least 15 and less than 40 
D) None of the above 
A) at least 2 and less than 5 
B) at least 5 and less than 10 
C) at least 15 and less than 40 
D) None of the above

Question 17

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students.   What are the number of degrees of freedom after removing the second observation (value = 100)?

Accepted Answer

A) 11 
B) 10 
C) 9 
D) 8 
A) 11 
B) 10 
C) 9 
D) 8

Question 18

We wish to see if the electronic control indicating the oven temperature for a certain model oven is properly calibrated.Four ovens of this model are selected at random.The electronic control on each is set to 300°F;after 1 hour,the actual temperature of each is measured.The temperatures measured are 305°F,310°F,300°F,and 305°F.Assume that the distribution of the actual temperatures for this model when the electronic control is set to 300°F is Normal.To test if the electronic control is properly calibrated,we will test the following hypotheses: H0: F1F1F1S1F1F1F10 = 300 versus Ha: F1F1F1S1F1F1F10 F1F1F1S1F1F1F10 300.Assume the standard deviation for the distribution of actual temperatures for all ovens of this model when the electronic control is set to 300°F is F1F1F1S1F1F1F10 = 4.At the 5% significance level,what is the power of our test when,in fact,F1F1F1S1F1F1F10 = 310°F?

Accepted Answer

A) 0.0345 
B) 0.9655 
C) 0.9959 
D) 0.9988 
A) 0.0345 
B) 0.9655 
C) 0.9959 
D) 0.9988

Question 19

Researchers have selected a simple random sample of size n = 12 from a population for the purpose of testing the null hypothesis H0: F1F1F1S1F1F1F10 = F1F1F1S1F1F1F100 against the alternative hypothesis Ha: F1F1F1S1F1F1F10 > F1F1F1S1F1F1F100.Studies indicate that a substantial degree of skewness can be expected in the population from which the sample was obtained.What might the researchers consider doing in this situation?

Accepted Answer

A) There really isn't anything they can do;they simply have to proceed with what the data give them. 
B) They might proceed as usual but alter the P-value later to compensate for the skewness in their data. 
C) They might use a test procedure that doesn't require Normality,such as a sign test using the median. 
D) They might apply a transformation to the data,such as a logarithm,to try to achieve symmetry. 
E) C and D are each possible approaches they might consider using. 
A) There really isn't anything they can do;they simply have to proceed with what the data give them. 
B) They might proceed as usual but alter the P-value later to compensate for the skewness in their data. 
C) They might use a test procedure that doesn't require Normality,such as a sign test using the median. 
D) They might apply a transformation to the data,such as a logarithm,to try to achieve symmetry. 
E) C and D are each possible approaches they might consider using.

Question 20

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students.   What did you notice from your preliminary analysis of the data?

Accepted Answer

A) The data were not approximately normal. 
B) There are outliers. 
C) The data are normal. 
D) A and B are both correct. 
A) The data were not approximately normal. 
B) There are outliers. 
C) The data are normal. 
D) A and B are both correct.

One-sample t test procedures are for use on subjects that are _______.

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students. What is the standard error of the mean?

A study was done to determine whether there is a difference in the amount of time (in hours)that graduate students versus undergraduate students spend on the Internet per day.The results of the analysis are shown below. The alternative hypothesis was _____.

Matched-pairs t procedures are for use on subjects that are _______.

The t procedures will be exact when the sample size is very large.

When the sample size is very large,the corresponding t distribution is very close to the normal distribution.

When calculating a one-sample t confidence interval,which level of confidence will give the largest interval?

The P-values for a one-sided hypothesis test are generally _____ the P-values for the two-sided hypothesis test on the same data.

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students. What is the value of the t statistic after removing the second observation (value = 100)?

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students. Would a t procedure be appropriate for these data?

Let n₁ represent the sample size of the first group and n₂ the sample size of the second group.A t procedure can be used when n₁ + n₂is ____ as long as there are no outliers.

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students. What are the number of degrees of freedom after removing the second observation (value = 100)?

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students. What did you notice from your preliminary analysis of the data?

Looking at Datadistributions

Looking at Datarelationships

Producing Data

Probability: the Study of Randomness

Sampling Distributions

Introduction to Inference

Inference for Proportions

Inference for Categorical Data

Inference for Regression

Multiple Regression

One-Way Analysis of Variance

Two-Way Analysis of Variance

Logistic Regression

Nonparametric Tests

Bootstrap Methods and Permutation Tests

Statistics for Quality: Control and Capability

Filters

Exam 7: Inference for Means

One-sample t test procedures are for use on subjects that are _______.

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students. What is the standard error of the mean?

A study was done to determine whether there is a difference in the amount of time (in hours)that graduate students versus undergraduate students spend on the Internet per day.The results of the analysis are shown below. The alternative hypothesis was _____.

Matched-pairs t procedures are for use on subjects that are _______.

The t procedures will be exact when the sample size is very large.

When the sample size is very large,the corresponding t distribution is very close to the normal distribution.

When calculating a one-sample t confidence interval,which level of confidence will give the largest interval?

The P-values for a one-sided hypothesis test are generally _____ the P-values for the two-sided hypothesis test on the same data.

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students. What is the value of the t statistic after removing the second observation (value = 100)?

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students. Would a t procedure be appropriate for these data?

Let n1 represent the sample size of the first group and n2 the sample size of the second group.A t procedure can be used when n1 + n2 is ____ as long as there are no outliers.

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students. What are the number of degrees of freedom after removing the second observation (value = 100)?

You are interested in determining if the average amount of time (in hours)that students spend on the Internet per day is greater than 2 hours.The data below are from a random sample of 11 students. What did you notice from your preliminary analysis of the data?

Looking at Datadistributions

Looking at Datarelationships

Producing Data

Probability: the Study of Randomness

Sampling Distributions

Introduction to Inference

Inference for Proportions

Inference for Categorical Data

Inference for Regression

Multiple Regression

One-Way Analysis of Variance

Two-Way Analysis of Variance

Logistic Regression

Nonparametric Tests

Bootstrap Methods and Permutation Tests

Statistics for Quality: Control and Capability

Filters

Let n₁ represent the sample size of the first group and n₂ the sample size of the second group.A t procedure can be used when n₁ + n₂is ____ as long as there are no outliers.