Returning to the Lung function data set from PMA6, lets analyze the relationship between height and FEV for fathers in this data set.
There does appear to be a tendency for taller men to have higher FEV1. The trend is linear, the red lowess trend line follows the blue linear fit line quite well.
Let’s fit a linear model and report the regression parameter estimates.
The least squares equation is \(Y = -4.09 + 0.118X\). We can calculate the confidence interval for that estimate using the
|2.5 %||97.5 %|
For ever inch taller a father is, his FEV1 measurement significantly increases by .12 (95%CI: .09, .15, p<.0001).