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Consider the three histograms shown below. Each are based on n = 900 observations.   Match the histograms to the corresponding box plots.

We have access to the complete dataset of all ages (in years) at death for First Ladies of the U.S. who have passed. From this data set we know that the average age at death is 71.7 years. You are interested in how the sample statistics vary for different samples of size n=15 from this population.   A sampling distribution is constructed where one of the samples is used to create a bootstrap distribution.    This sample has mean: x-bar = 78 years. Below are boxplots of the sample of size n = 15, the sampling distribution, and the bootstrap distribution (although not necessarily in that order!).  Use all of the provided information to select the correct reason for each Boxplot identification. Boxplot A is the sample of n = 15 because it centered at the [answer5] where the sample standard deviation (s) is [answer6] the value of the standard error found with the sampling distribution. Boxplot B is the sampling distribution because it is centered at the [answer1] and has a standard error that is roughly equal to the estimated standard error found with the [answer2]. Boxplot C is the bootstrap distribution because it is centered at the [answer3] and has an estimated standard error that is roughly equal to the standard error found with the [answer4].

Consider each scenario and decide which statistical procedure should be used to answer the question. Scenario A: On average, do people who regularly exercise have a lower resting pulse rate (beats/minute)  when considering Stat 200 students. A random sample 40 Stat 200 students who regularly exercise and a random sample of 40 Stat 200 students who don’t regularly exercise were obtained.  The resting pulse rate was determined for each Stat 200 student. Scenario B: On average, do most people desire to be taller?  A random sample of adults were asked:  what is your actual height (inches) and what is your ideal height (inches).  A difference was computed for adult person when considering the two samples.  With Scenario A, we should use the [answer1] procedure.   With Scenario B, we should use the [answer2] procedure.

Two researchers perform two different hypothesis tests.   Researcher A obtained a p-value of 0.03. Researcher B obtained a p-value of 0.15 Based on this information, the p-value from researcher [answer1] gives stronger evidence against the null and in favor of the alternative.  Using a significance level of 0.05, researcher A should [answer2] the null and researcher B should [answer3] the null.

Penn State University Health Services believe that less than 35% of current students have engaged in binge drinking. To test this claim, they survey n = 1343 randomly selected Penn State students, asking them whether or not they engaged in binge drinking. In the sample, they find that 34.4% of students have engaged in binge drinking. The correct null and alternative hypotheses for this situation would be: Ho:[answer1][answer2][answer3] Ha:[answer4][answer5][answer6] Assuming the relevant p-value for this test was 0.372, complete the conclusion below: We [answer7] the null hypothesis.  We [answer8] convincing evidence that less than 35% of Penn State students have engaged in binge drinking.

Consider each of the samples below and determine whether or not conditions are met to use a t-distribution for inference about the population mean. A.   B. C. D.  

Researchers are interested in determining if there is an association between the number of hours a student works in a week and the number of classes they miss in a week.  Assume data was collected and they found a correlation of 0.623. Using this information, they calculated a p-value of 0.014. Determine whether each of the statements below is true or false.

Research Question:  Does the data suggest that less than 60% of Americans have at least $1000 in the bank for an emergency. The sample statistic of interest is p-hat: the proportion of Americans who do have at least $1000 in the bank for an emergency. Company A surveys 240 Americans with a sample proportion of 0.58. Company B surveys 410 Americans with a sample proportion of 0.58. Company C surveys 80 Americans with a sample proportion of 0.58. Which Company has the most evidence against the null hypothesis, i.e. in favor of the research question?

Assume a researcher performs a hypothesis test and uses the below screenshot from StatKey to calculate the p-value: Look at all of the provided information on the graph when answering this question.   The alternative hypothesis of Ha: [answer1] is the only possibility because the p-value was obtained from the theoretical [answer2] distribution and the test is [answer3].

Netflix claims that 50% of U.S. households now have a subscription. We want to find evidence that the true percentage is different. A survey of n = 472 randomly chosen U.S. households finds that the proportion who have a subscription to Netflix is 46%. The correct null and alternative hypotheses for this situation would be: Ho:[answer1][answer2][answer3] Ha:[answer4][answer5][answer6] Assuming the relevant p-value for this test was 0.002, complete the conclusion below: We [answer7] the null hypothesis.  We [answer8] convincing evidence that the proportion of U.S. households with a subscription to Netflix is different than 0.50.