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An experiment is conducted to show that blood pressure can be consciously reduced in people trained in a "biofeedback exercise program." Six subjects were randomly selected and blood pressure measurements were recorded before and after the training. The difference between blood pressures was calculated (after - before) producing the following results: ${\stackrel{¯}{x}}_d=-10.2{\mathrm{s}}_d=8.4$. Using the data, test the hypothesis that the blood pressure has decreased after the training.

The distribution for the test is:

a.$t_5$

b.$t_6$

c.$N(-10.2,8.4)$

d.$\mathrm{N}\left(-10.2,\frac{8.4}{\sqrt{6}}\right)$

Use the following information to answer the next 15 exercises: Indicate if the hypothesis test is for

a. independent group means, population standard deviations, and/or variances known

b. independent group means, population standard deviations, and/or variances unknown

c. matched or paired samples

d. single mean

e. two proportions

f. single proportion

Varsity athletes practice five times a week, on average.

A golf instructor is interested in determining if her new technique for improving players' golf scores is effective. She takes four new students. She records their 18 -hole scores before learning the technique and then after having taken her class. She conducts a hypothesis test. The data are as follows.

The correct decision is

a. Reject$H_0$

b. Do not reject$H_0$

A local cancer support group believes that the estimate for new female breast cancer cases in the south is higher in 2013 than in 2012. The group compared the estimates of new female breast cancer cases by southern state in 2012 and in 2013. The results are in Table 10.32.

A traveler wanted to know if the prices of hotels are different in the ten cities that he visits the most often. The list of the cities with the corresponding hotel prices for his two favorite hotel chains is in Table 10.33. Test at the$1\%$ level of significance.

A study is done to determine if students in the California state university system take longer to graduate than students enrolled in private universities. One hundred students from both the California state university system and private universities are surveyed. From years of research, it is known that the population standard deviations are 1.5811 years and one year, respectively.

Indicate which of the following choices best identifies the hypothesis test.

a. Independent group means, population standard deviation and/or variances known

b. Independent group means, population standard deviation and/or variances unknown

c. Matched or paired samples.

d. Single mean

e. Two proportions.

f. Single proportion.

Use the following information to answer the next 15 exercises: Indicate if the hypothesis test is for

a. independent group means, population standard deviations, and/or variances known

b. independent group means, population standard deviations, and/or variances unknown

c. matched or paired samples

d. single mean

e. two proportions

f. single proportion

A sample of 12 in-state graduate school programs at school A has a mean tuition of \(64,000 with a standard deviation of \)8,000. At school B, a sample of 16 in-state graduate programs has a mean of \(80,000 with a standard deviation of \)6,000. On average, are the mean tuitions different?

A new SAT study course is tested on $12$individuals. Pre-course and post-course scores are recorded. Of interest is the mean increase in SAT scores. The following data are collected:

$\begin{array}{|ll|}\hline \text{Pre-course score}& \text{Post-course score}\\ 1& 300\\ 960& 920\\ 1010& 1100\\ 840& 880\\ 1100& 1070\\ 1250& 1320\\ 860& 860\\ 1330& 1370\\ 790& 770\\ 990& 1040\\ 1110& 1200\\ 740& 850\\ \hline\end{array}$

A golf instructor is interested in determining if her new technique for improving players’ golf scores is effective. She takes four (4) new students. She records their $18$-hole scores before learning the technique and then after having taken her class. She conducts a hypothesis test. The data are as Table 10.37.

$\begin{array}{|lllll|}\hline & \text{Player 1}& \text{Player 2}& \text{Player 3}& \text{Player 4}\\ \text{Mean score before class}& 83& 78& 93& 87\\ \text{Mean score after class}& 80& 80& 86& 86\\ \hline\end{array}$

This is:

a. a test of two independent means.

b. a test of two proportions.

c. a test of a single mean.

d. a test of a single proportion.

Use the following information to answer the next 15 exercises: Indicate if the hypothesis test is for

a. independent group means, population standard deviations, and/or variances known

b. independent group means, population standard deviations, and/or variances unknown

c. matched or paired samples

d. single mean

e. two proportions

f. single proportion

A new WiFi range booster is being offered to consumers. A researcher tests the native range of 12 different routers under the same conditions. The ranges are recorded. Then the researcher uses the new WiFi range booster and records the new ranges. Does the new WiFi range booster do a better job?