7. (10 points) The college instructor wants to know if there is a difference between two exam scores among a group of students in his Calculus 1 class. He records the exam score for both exams in data file Q4 for any particular student selected for the study. Which hypothesis test should he conduct to determine if there is a difference between exam scores among both of their exams? Test at the \( 5 \% \) level of significance whether the data provide sufficient evidence to conclude that exam 1 has lower mean scores than exam 2. 8. (15 points) A public health researcher is interested in social factors that influence heart disease. He surveys 50 towns and gathers data on the percentage of people in each town who smoke, the percentage of people in each town who bike to work, people's age, blood pressure, diabetes, and the percentage of people in each town who have heart disease (see Q5). (a) Assess each variable separately first (obtain measures of central tendency and dispersion, frequency distributions, and graphs) (b) Assess the relationship of each independent variable, one at a time, with the dependent variable and the relationships between all of the independent variables with each other (calculate the correlation coefficient and obtain a scatter plot). Are the two variables linearly related? (c) Which variable is the best predictor of heart disease? Why? (d) Run a simple linear regression to predict heart disease based on the best predictors. (e) Interpret your regression model based on the \( R \) output
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The instructor should conduct a paired t-test. This test is used to compare the means of two related groups to determine if there is a significant difference between them. In this case, the two related groups are the same students' scores on two different exams. Show more…
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