A sociology student does a study to determine whether people who exercise live longer.He claims that someone who exercises 7 days a week will live 15 years longer than someone who doesn't exercise at all.
A)Predictions based on a regression line are for average values of x and y.The actual average life expectancy changes every year so an accurate prediction is impossible.
B)There is nothing wrong with the interpretation.
C)Predictions based on a regression line are for average values of y for a given x.The actual life expectancy will vary around the prediction.
D)The $\mathrm { R } ^ { 2 }$ has to be greater than 90% to make a statement like this.
E)A linear model is inappropriate for sociology studies.

Question

Quizplus · Accepted Answer

Predictions based on a regression line are for average values of y for a given x. The actual life expectancy will vary around the prediction, and this variation depends on the amount of variability in the data and the strength of the relationship between exercise and life expectancy. Therefore, the claim that someone who exercises 7 days a week will live 15 years longer than someone who doesn't exercise at all should be interpreted with caution, especially if the study did not account for other factors that may affect life expectancy.

A Sociology Student Does a Study to Determine Whether People R2\mathrm { R } ^ { 2 }R2

A Sociology Student Does a Study to Determine Whether People $\mathrm { R } ^ { 2 }$