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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?

Using the following information select the appropriate interpretation for the correlation coefficient: Variables being compared are number of years of experience at a job and annual salary. r = -0.78

A biostatistician finds the relationship between the number of weeks (X) spent in a hospital and number of seizures per week (Y) and is described by the following equation: .  This is based on a sample size of 50 patients and the associated coefficient of correlation is r = .19. Using this information above, answer the following question: How do you interpret r = .19?

Calculate the appropriate test statistic based on the information provided (round your answer to 4 decimal places): Research Question: Do people who work in offices exercise fewer days per month than people who are day laborers? DO NOT ASSUME THE POPULATION STANDARD DEVIATIONS OF THE TWO SAMPLES ARE EQUAL Group 1: Work in Office Sample mean = 15.5 Sample standard deviation = 5 Sample size = 16   Group 2: Day Laborers Sample mean = 18.2 Sample standard deviation = 7 Sample size = 14

Calculate the upper bound of a 95% confidence interval for sample mean of the given data (round your answer to 4 decimal places):   Population mean = 27.35 Sample mean = 26.25 Sample standard deviation = 3 Sample size = 25

Twelve students were randomly selected from the College of Public Health and their diastolic blood pressure was tested. The sample mean and standard deviation were 79.0 mmHg and 2.2 mmHg respectively. What is the obtained t-score for this sample under the null hypothesis Ho: µ = 80?

Calculate the appropriate test statistic based on the information provided (round your answer to 4 decimal places): Research Question: Do more than 70% of people who work from home play video games? Population proportion = 70% Number of people from sample who said they play video games = 42 Sample size = 50

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)?

In One Sample Proportion test, it is important to convert the sample proportion to a z-score first. In this example, we selected a random sample of size 120 from a pool of university students and asked whether they use the university gym on a regular basis. Eighty replied yes. Assuming that the population proportion under the null hypothesis is 50%, what is the z-score (test statistics) for the sample proportion?

Using the information below calculate the predicted value for Y for the given value of X. Y (Dependent Variable) = Grade Point Average X (Independent Variable) = Average number of hours spent studying per week   yhat = 2 + 0.196*X   On average what would a person’s Grade Point Average be if they spend on average 8 hours studying per week (round your answer to 4 decimal places)?