Blog

The World Health Organization collected data on obesity in 1…

The World Health Organization collected data on obesity in 182 countries around the world.  The following graph shows the percent people who are “overweight or obese,” where the individuals have been grouped into separate categories according to their country’s income level.                   Which one statement below best describes the graph?

The New England Journal of Medicine reported that people who…

The New England Journal of Medicine reported that people who suffer a cardiac arrest in public places like casinos have a higher survival rate than those who have a heart attack in a hospital.  Which one of the following is a valid interpretation of this finding?

Lake Superior has ice for a long period each winter.   Below…

Lake Superior has ice for a long period each winter.   Below is some data and a scatterplot of the number of days ice was present at one of the stations on Lake Superior versus the mean temperature for the months of December through April, for nine seasons (1966-67 through 1974-75).                         The least squares regression line fit to this data is Days of Ice = 253.0 – 6.254 x Mean Temperature.   with r-squared = 57.1%.  Which of the following is the correct interpretation of r-squared?

From 1986 to 2000, a study followed a large number of male h…

From 1986 to 2000, a study followed a large number of male health professionals age 40 to 75.  Each respondent filled out a lifestyle questionnaire every two years.  The 22,086 subjects who reported having good erectile function in 1986 were included in an analysis of risk factors for the development of erectile dysfunction.  This is a(n)