knitr::opts_chunk$set(eval = FALSE)

Is there an association between the weight and the fuel efficiency of cars? To find out, we use the `mtcars`

dataset from the `datasets`

package. The `mtcars`

data originally came from the 1974 Motor Trend US magazine, and it contains design and performance data on 32 models of automobile.

# ?mtcars # more info head(mtcars)

Here, `wt`

is weight in tons, and `mpg`

is fuel efficiency in miles per gallon. We want to figure out if there is an association between `wt`

and `mpg`

. The `mtcars`

dataset itself only has 32 rows, so we generated two larger bootstrapped datasets. We called them `small`

and `large`

.

Then, we fit a couple regression models to the `small`

and `large`

to try to detect an association between `wt`

and `mpg`

. Here are the coefficients and p-values from one of the model fits.

readd(coef_regression2_small)

Since the p-value on `x2`

is so small, there may be an association between weight and fuel efficiency after all.