BIOS 3000 R Assignment 5

What is the 95% confidence interval for the sex-adjusted coefficient for age?

(0.2062776, 0.2346130)

What is the 95% interval for the predicted FEV value of a single 12-year-old female?

(1.779387, 3.825041)

How many of the variables have been flagged as problematic regarding multicollinearity?

0

What is the estimated sex-adjusted coefficient for age?

0.220445

What is the estimated coefficient for age?

0.222041

What is the predicted FEV value for a 12-year-old female?

2.802214 liters

What is the p-value for the test of interaction?

4.47×10−15

What is the interpretation of the estimated sex-adjusted coefficient for age?

It is estimated that, after adjusting sex, forced expiratory volume increases by 0.220445 liters for every one year increase in age.

What is the magnitude of confounding? Does sex confound the relationship between fev and age?

Since the magnitude of confounding is 0.724%, sex does not confound the relationship between fev and age.

After performing stepwise selection, what is the regression equation of the resulting model?

fev = −4.456974 + 0.065509(age) + 0.157103(sex) − 0.087246(smoke) + 0.104199(height)