A researcher would like to study BMI levels in adults 20-40 years of age. She selected 9 patients and found their BMI values to be: 18, 29, 36, 22, 25, 27, 26, 30, 37The standard deviation of BMI levels of this group of patients is

In one study on the effect of Dyazide on blood pressure level, 200 subjects who reported taking Dyazide for a long period of time had their blood pressure levels compared with those of 200 people who had never taken Dyazide. In a second study, 25 subjects were randomly chosen to receive Dyazide and 25 were chosen to receive a placebo.Which of the following statement is correct?

Suppose you wish to determine if students in the College of Public Health have higher GPAs than that of students in the college of Medicine at USF.  If you randomly select 50 students with GPA’s above 3.0 after they graduated and 50 students with GPA’s below 3.0 after they graduated then checked their student records to look back at what college they first enrolled in, then compare GPAs what type of study was conducted?

A biostatistician finds the relationship between the number of weeks (X) spent in a hospital and number of seizures per week (Y) andis described by the following equation: .  This is based on a sample size of 50 patients and the associated coefficient of correlation is r = .93. Using this information above, answer the following question: How do you interpret r = .93?

Calculate the lower bound of a 95% confidence interval for the difference in sample means for the given data (round your answer to 4 decimal places):   DO NOT ASSUME THE POPULATION STANDARD DEVIATIONS OF THE TWO SAMPLES ARE EQUAL Group 1: Carpenter Sample mean = 60000 Sample standard deviation = 5500 Sample size = 10   Group 2: Crane Operator Sample mean = 62500 Sample standard deviation = 2500 Sample size = 14

Five hundred women are enrolled in a study to evaluate the accuracy of a test for pregnancy. 200 of the women were actually pregnant. 170 of the pregnant women had a positive test as did 40 of the women who were not pregnant. What is the probability (i.e., NPV) that a woman is not pregnant given that she tested negative on a screening test? Test                         Pregnant? Yes No Total + 170 40 210 – 30 260 290 Total 200 300 500

Conduct a hypothesis test based on the following information using a significance level of 1%: Research Question: Are people running more than 20.95 miles per week? Population standard deviation was NOT KNOWN Test statistic = 2.57 Sample size = 25

Using the information below calculate the predicted value for Y for the given value of X. Y (Dependent Variable) = Cost of a car in thousands of dollars (i.e. Y = 1 means one-thousand dollars) X (Independent Variable) = Miles per Gallon in city traffic   yhat = 28.1 + 0.62*X   On average how many thousands of dollars would a car cost if it gets 15 Miles per Gallon in city traffic (round your answer to 4 decimal places)?

Conduct a hypothesis test based on the following information using a significance level of 1%: Research Question: does the proportion of students taking out student loan debt equal 50%?   Test statistic = 2.83 sample size = 50

Select the appropriate interpretation for the slope of the linear regression equation below. Y (Dependent Variable) = Cost of an annual pass to Disney in dollars X (Independent Variable) = Average number of people who visit each day in thousands of people   yhat = 2122.86 – 30*X