Introductory Statistics

Neil A. Weiss

Chapter 10

Inferences for Two Population Means - all with Video Answers

Educators

Section 0

Which Procedure Should Be Used?

Problem 195

We considered three hypothesis-testing procedures based on independent simple random samples to compare the means of two populations with unknown standard deviations.
a. Identify the three procedures by name.
b. List the conditions for using each procedure.
c. Identify the test statistic for each procedure.

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 196

We examined two hypothesis-testing procedures based on a simple random paired sample to compare the means of two populations.
a. Identify the two procedures by name.
b. List the conditions for using each procedure.
c. Identify the test statistic for each procedure.

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 197

Suppose that you want to perform a hypothesis test based on independent simple random samples to compare the means of two populations. Assume that the variable under consideration is normally distributed on each of the two populations and that the population standard deviations are equal.
a. Identify the procedures discussed in this chapter that could be used to carry out the hypothesis test, that is, the procedures whose assumptions are satisfied.
b. Among the procedures that you identified in part (a), which is the best one to use? Explain your answer.

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 198

Suppose that you want to perform a hypothesis test based on independent simple random samples to compare the means of two populations. Assume that the variable under consideration is normally distributed on each of the two populations and that the population standard deviations are unequal.
a. Identify the procedures discussed in this chapter that could be used to carry out the hypothesis test, that is, the procedures whose assumptions are satisfied.
b. Among the procedures that you identificd in part (a), which is the best one to use? Explain your answer.

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 199

Suppose that you want to perform a hypothesis test based on independent simple random samples to compare the means of two populations. Assume that the two distributions of the variable under consideration have the same shape but are not normally distributed and that the sample sizes are both large.a. Identify the procedures discussed in this chapter that could be used to carry out the hypothesis test, that is, the procedures whose assumptions are satisfied.
b. Among the procedures that you identificd in part (a), which is the best one to use? Explain your answer.

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 200

Suppose that you want to perform a hypothesis test based on a simple random paired sample to compare the means of two populations. Assume that the paired-difference variable is normally distributed.
a. Identify the procedures discussed in this chapter that could be used to carry out the hypothesis test, that is, the procedures whose assumptions are satisfied.
b. Among the procedures that you identified in part (a), which is the best one to use? Explain your answer.

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 201

Suppose that you want to perform a hypothesis test based on a simple random paired sample to compare the means of two populations. Assume that the paired-difference variable has
a nonnormal symmetric distribution and that the sample size is large.
a. Identify the procedures discussed in this chapter that could be used to carry out the hypothesis test, that is, the procedures whose assumptions are satisfied.
b. Among the procedures that you identificd in part (a), which is the best one to use? Explain your answer.

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 202

We provide a type of sampling $($ independent or paired), sample size(s), and a figure showing the results of preliminary data analyses on the sample(s). For independent samples, the graphs are for the two samples: for a paired sample, the graphs are for the paired differences. The intent is to employ the sample data to perform a hypothesis test to compare the means of the two populations from which the data were obtained. In each case, use the information provided and the flow chart shown in Fig. 10.19 on page 502 to decide which procedure should be applied.
Paired; $n=75 ;$ Fig. 10.22

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 203

We provide a type of sampling $($ independent or paired), sample size(s), and a figure showing the results of preliminary data analyses on the sample(s). For independent samples, the graphs are for the two samples: for a paired sample, the graphs are for the paired differences. The intent is to employ the sample data to perform a hypothesis test to compare the means of the two populations from which the data were obtained. In each case, use the information provided and the flow chart shown in Fig. 10.19 on page 502 to decide which procedure should be applied.
Independent; $n_{1}=25$ and $n_{2}=20 ;$ Fig. 10.23

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 204

We provide a type of sampling $($ independent or paired), sample size(s), and a figure showing the results of preliminary data analyses on the sample(s). For independent samples, the graphs are for the two samples: for a paired sample, the graphs are for the paired differences. The intent is to employ the sample data to perform a hypothesis test to compare the means of the two populations from which the data were obtained. In each case, use the information provided and the flow chart shown in Fig. 10.19 on page 502 to decide which procedure should be applied.
Independent; $n_{1}=17$ and $n_{2}=17 ;$ Fig. 10.24

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 205

We provide a type of sampling $($ independent or paired), sample size(s), and a figure showing the results of preliminary data analyses on the sample(s). For independent samples, the graphs are for the two samples: for a paired sample, the graphs are for the paired differences. The intent is to employ the sample data to perform a hypothesis test to compare the means of the two populations from which the data were obtained. In each case, use the information provided and the flow chart shown in Fig. 10.19 on page 502 to decide which procedure should be applied.
Independent; $n_{1}=40$ and $n_{2}=45 ;$ Fig. 10.25

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 206

We provide a type of sampling $($ independent or paired), sample size(s), and a figure showing the results of preliminary data analyses on the sample(s). For independent samples, the graphs are for the two samples: for a paired sample, the graphs are for the paired differences. The intent is to employ the sample data to perform a hypothesis test to compare the means of the two populations from which the data were obtained. In each case, use the information provided and the flow chart shown in Fig. 10.19 on page 502 to decide which procedure should be applied.
Independent; $n_{1}=20$ and $n_{2}=15 ;$ Fig. 10.26

Maxime Rossetti

Maxime Rossetti

Numerade Educator

Problem 207

We provide a type of sampling $($ independent or paired), sample size(s), and a figure showing the results of preliminary data analyses on the sample(s). For independent samples, the graphs are for the two samples: for a paired sample, the graphs are for the paired differences. The intent is to employ the sample data to perform a hypothesis test to compare the means of the two populations from which the data were obtained. In each case, use the information provided and the flow chart shown in Fig. 10.19 on page 502 to decide which procedure should be applied.
Paired; $n=18 ;$ Fig. 10.27

Maxime Rossetti

Maxime Rossetti

Numerade Educator