91影视

A total of $25$repetitions of the simulation were performed. The number of makes in each set of $10$simulated shots was recorded on the dotplot. What is the approximate probability that a $47\%$shooter makes $5$or more shots in $10$attempts?

(a) $\frac{5}{10}$

(b) $\frac{3}{10}$

(c) $\frac{12}{25}$

(d) $\frac{3}{25}$

(e)$\frac{47}{100}$

Suppose this player attempts $10$shots in a game and makes only $3$of them. Does this provide convincing evidence that she is less than a $47\%$shooter?

a. Yes, because $3/10$($30\%$) is less than $47\%$

b. Yes, because she never made $47\%$of her shots in the simulation.

c. No, because it is plausible (believable) that she would make $3$or fewer shots by chance alone.

d. No, because the simulation was only repeated $25$times.

e. No, because more than half of the simulated results were less than$47\%$

Ten percent of U.S. households contain $5$or more people. You want to simulate choosing a household at random and recording 鈥淵es鈥� if it contains $5$or more people. Which of these is a correct assignment of digits for this simulation?

a.$Odd=Yes;Even=No$

b.$0=Yes;1鈥�9=No$

c.$0鈭�5=Yes;6鈭�9=No$

d.$0鈭�4=Yes;5鈭�9=No$

e. None of these

Suppose this player attempts $10$shots in a game and makes only $3$of them. Does this provide convincing evidence that she is less than a $47\%$shooter?

a. Yes, because $\frac{3}{10}$($30\%$) is less than $47\%$.

b. Yes, because she never made $47\%$of her shots in the simulation.

c. No, because it is plausible (believable) that she would make $3$or fewer shots by chance alone.

d. No, because the simulation was only repeated $25$times.

e. No, because more than half of the simulated results were less than$47\%.$

Ten percent of U.S. households contain $5$or more people. You want to simulate choosing a household at random and recording 鈥淵es鈥� if it contains $5$or more people. Which of these is a correct assignment of digits for this simulation?

a. $Odd=Yes;Even=No$

b. $0=Yes;1-9=No$

c. $0-5=Yes;6-9=No$

d. $0-4=Yes;5-9=No$

e. None of these

To find out what proportion of Americans support proposed Medicare legislation to help pay medical costs, the AARP conducted a survey of their members (people over age $50$who pay membership dues). One of the questions was: 鈥淓ven if this plan won鈥檛 affect you personally either way, do you think it should be passed so that people with low incomes or people with high drug costs can be helped?鈥� Of the respondents, $75\%$answered 鈥淵es.鈥�

a. Describe how undercoverage might lead to bias in this study. Explain the likely direction of the bias.

b. Describe how the wording of the question might lead to bias in this study. Explain the likely direction of the bias.

AARP, and Medicare (4.1) To find out what proportion of Americans support proposed

Medicare legislation to help pay medical costs, the AARP conducted a survey of their

members (people over age $50$ who pay membership dues). One of the questions was:

鈥淓ven if this plan won鈥檛 affect you personally either way, do you think it should be passed

so that people with low incomes or people with high drug costs can be helped?鈥� Of the

respondents, $75\%$ answered 鈥淵es.鈥�

a. Describe how undercoverage might lead to bias in this study. Explain the likely

direction of the bias.

b. Describe how the wording of the question might lead to bias in this study. Explain the

likely direction of the bias.

Mammograms Many women choose to have annual mammograms to screen for breast

cancer after age $40$. A mammogram isn鈥檛 foolproof. Sometimes the test suggests that a

woman has breast cancer when she really doesn鈥檛 (a 鈥渇alse positive鈥�). Other times the test

says that a woman doesn鈥檛 have breast cancer when she actually does (a 鈥渇alse negative鈥�).

Suppose the false negative rate for a mammogram is $0.10.$

a. Explain what this probability means.

b. Which is a more serious error in this case: a false positive or a false negative? Justify

your answer.

Waiting to park Do drivers take longer to leave their parking spaces when

someone is waiting? Researchers hung out in a parking lot and collected some data. The

graphs and numerical summaries display information about how long it took drivers to

exit their spaces.

a. Write a few sentences comparing these distributions.

b. Can we conclude that having someone waiting causes drivers to leave their spaces more

slowly? Why or why not?

Do drivers take longer to leave their parking spaces when someone is waiting? Researchers hung out in a parking lot and collected some data. The graphs and numerical summaries display information about how long it took drivers to exit their spaces.

a. Write a few sentences comparing these distributions.

b. Can we conclude that having someone waiting causes drivers to leave their spaces more slowly? Why or why not?