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The Central Limit Theorem is important in Statistics because it allows us to use the normal distribution to make inferences concerning the population mean:

Which of the following methods of graphing sample data can help you in determining the shape of a frequency distribution for the variable height (measured in inches)?

Say a study is interested in determining the average success rate of surgeons in the USA.  The researchers randomly select many hospitals over the country and contact surgeons in these hospitals and obtain their surgical files, but the surgical files do not contain the information need to accurately calculate each surgeons success rate.  The researchers use the files to calculate the success rate for each surgeon as best as they are able, but know the numbers are not exactly accurate.  What type of bias is this study most likely to suffer from?

Using the information below calculate the predicted value for Y for the given value of X. Y (Dependent Variable) = Cost of a house in thousands of dollars (i.e. Y = 1 means one-thousand dollars) X (Independent Variable) = number of miles from an elementary school   yhat =  325 – 6*X   On average how many thousands of dollars will a house cost if it is 15 miles from an elementary school (round your answer to 4 decimal places)?

Income of USF Administration (in dollars) is

Fourteen students were randomly selected from the College of Public Health and their diastolic blood pressure was tested. The sample mean and standard deviation were 81.6 mmHg and 2.3 mmHg respectively. What is the obtained t-score for this sample under the null hypothesis Ho: µ = 80?

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