Data for Exercises 2.21 and 9.14

`Gym`

A data frame/tibble with eight observations on three variables

- age
age of child

- number
number of gymnastic activities successfully completed

Kitchens, L. J. (2003) *Basic Statistics and Data Analysis*.
Pacific Grove, CA: Brooks/Cole, a division of Thomson Learning.

```
plot(number ~ age, data = Gym)
model <- lm(number ~ age, data = Gym)
abline(model, col = "red")
summary(model)
#>
#> Call:
#> lm(formula = number ~ age, data = Gym)
#>
#> Residuals:
#> Min 1Q Median 3Q Max
#> -3.5213 -0.5904 -0.1596 1.6117 1.8404
#>
#> Coefficients:
#> Estimate Std. Error t value Pr(>|t|)
#> (Intercept) -0.03191 2.01387 -0.016 0.9879
#> age 1.63830 0.39881 4.108 0.0063 **
#> ---
#> Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
#>
#> Residual standard error: 1.933 on 6 degrees of freedom
#> Multiple R-squared: 0.7377, Adjusted R-squared: 0.694
#> F-statistic: 16.88 on 1 and 6 DF, p-value: 0.0063
#>
```