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From a random sample of 200 men from a men’s only health club, 40%, or 80, stated that they wished the club would stay open longer. The sample size is [answer1].  40% represents [answer2].

A random sample of 230 students in STAT 200 were asked whether or not they have ever been in a pedestrian accident while using technology. Forty six of these 230 STAT 200 students answered “yes.” The results are summarized in the Minitab output found below.   Using the provided 95% confidence interval, which is the correct interpretation? When considering STAT 200 students while using technology, we are 95% confident that the:

A mind reading experiment is done in which a subject tries to correctly identify which of 4 cards the researcher has randomly picked, where each card is equally likely. This is repeated for 200 trials. The null hypothesis is that the subject is guessing at random, while the alternative is that the subject can read minds and can guess the card selected at a rate higher than guessing at random. The subject actually gets 70 correct answers. Which of the following describes the probability represented by the p-value for this test? The probability of getting 70 or [answer1] correct, if the subject [answer2]. 

A news reporter writes an article with the headline “Coffee makes you smarter”. The article describes a study performed by surveying residents of a college town. Residents were asked the questions “How many cups of coffee do you drink daily?” and “How many years of post-secondary education have you completed?”. The researchers found a positive, linear association between the resulting variables.  Is the headline written for the article an accurate summary of the researchers’ results?

Fifteen students were asked how many nights a month do they study.  The responses are listed in the table found below.  Student 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Number of nights study/month 4 5 6 10 12 14 18 20 20 20 22 23 24 25 26 The mean is 16.6 nights/month Match the attribute of the sample with the appropriate answer.   

The amount of cooked beef in hamburgers was compared at two different fast-food places (Joe’s and Harry’s). The weights (in ounces) of hamburgers is obtained for: a sample from Joe’s and a sample from Harry’s, as shown below in the table.   Joe’s 4.2 4.8 4.9 4.4 4.7 4.1 4.5 4.4 4.3 Harry’s 4.5 4.9 4.6 4.7 5.1 4.8 5.0 4.7    Which of the following is being studied?

The five number summary for test scores (in points) was obtained from applicants who applied for a job is given by:   Min Q1 Med Q3 Max 42 48 50 52 60 Use the information from this five-number summary to identify the quantities listed below.

Researchers surveyed 50 students (group 1) sitting in the back half of the classroom and 15 students (group 2) sitting in the front half of the classroom and recorded their GPA.  The goal of the study was to see if, on average, the students that sat in the back half of the classroom have lower GPAs than those that sat in the front half. The sample statistic is -0.170 (using back minus front) with standard error 0.062.  The p-value is 0.032. 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.

Researchers test the provided hypotheses about two variables: ‘Favorite type of Apple’ (Red Delicious, Granny Smith, Honeycrisp, Empire, Gala) and ‘Time Zone where you Live: ‘(Pacific, Mountain, Central, Eastern) when based on a sample of n = 200 U.S. adults. H0: There is no association between favorite type of apple and time zone where you live. Ha: There is an association between favorite type of apple and time zone where you live Assume the researchers calculated a p-value of 0.246.  What is the correct conclusion for this hypothesis test using a significance level of 0.05?

Does reintroducing wolves into an ecosystem improve the overall health of the system (as measured by species richness)? A team of ecologists tested this on 30 different forested parks. Assume the researchers performed an experiment and calculated a p-value of 0.019.  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.