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Researchers surveyed n = 25 stat 200 female students to determine how many days out of the week they consume one or more alcoholic beverage. Their goal was to see if there was evidence that females students in stat 200 had consumed alcoholic beverages more than 2 days per week, on the average. The relevant sample statistic is 2.30 days per week with a standard error of 0.332 days per week.  The p-value is 0.188. Correctly complete the p-value interpretation below: The chance of seeing a test statistic of [answer1] = [answer2] or any value [answer3] is [answer4], if in fact the [answer5] hypothesis is true.

:Assume a researcher asks 125 Penn State students the following two questions   How do you typically commute to class from your home? (walk, bike, take bus, drive) Are you an only child?  (yes, no) The responses are summarized below. Yes    No    Total Walk 25 35 60 Bike 6 12 18 Take the bus 4 18 22 Drive 10 15 25 Total 45 80 125 When considering ‘Yes’ and ‘Bike’,  the correct calculation for the expected count is [answer1]. The correct interpretation of the expected count is: If the two variables are [answer2], we would expect that around [answer3] of children who [answer4] an “only child” to [answer5] when commuting from home to class.

Does burning areas of an ecosystem improve the performance of native grasses? A team of ecologists tested this on 50 fields. Assume the researchers performed an experiment and calculated a p-value of 0.024.  Complete the statements below: Using a significance level of 0.05, the researchers should [answer1] the null hypothesis. It is possible that they have committed a type [answer2] error.

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

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.