The most appropriate study design depends, among other things, on the distribution of
1.A) The risk factor in the population of interest
2.B) The participants
3.C) The outcome in the population of interest
Country Financial, a financial services company, uses surveys of adults age 18 and older to determine if personal financial fitness is changing over time. A recent sample of 1000 adults showed 410 indicating that their financial security was more than fair. Just a year before, a sample of 900 adults showed 315
indicating that their financial security was more than fair.
a. State the hypotheses that can be used to test for a significant difference between the
population proportions for the two years.
b. Conduct the hypothesis test and compute the p-value. At a .05 level of significance,
what is your conclusion?
c. What is the 95% confidence interval estimate of the difference between the two
population proportions? What is your conclusion?
Using the health records of ever student at a high school, the school nurse created a scatterplot relating y = height (in centimeters) to x = age (in years).
After verifying that the conditions for the regression model were met, the nurse calculated the equation of the population regression line to be
About what percent of 15-year-old students at this school are taller than 180 cm?