Question

A weight loss company wanted to predict how much weight a client would lose if they followed a prescribed exercise program in addition to the company's diet program. Volunteers were randomly divided into two groups, one group dieted but didn’t exercise, and the other group dieted and followed the exercise program. For the exercise group, they used linear regression with percent compliance with the exercise program as the explanatory variable and pounds lost in three months as the response variable.

For the study in the previous question, the value of b1b1 for the regression line was 0.05 pounds. Interpret this statistic.

  

The average weight loss of all participants was 0.05 pounds.

   

On average, the exercise participants lost 0.05 pounds more than non-exercisers.

  

As percent compliance goes up by 1 percent, the average weight lost in three months increases by 0.05 pounds.

As the number of pounds lost increases by 1 lbs, the percent compliance on average increases by 5%.

Answer 1

b1 = 0.05

The slope of a line (b1) is the change in y divided by the change in x, which is a rate of change. Stating the units for y and x will help clarify what the slope tells you about how the y-value changes from one x-value to the next.

Answer: As percent compliance goes up by 1 percent, the average weight lost in three months increases by 0.05 pounds.