`R/BSDA-package.R`

`Randd.Rd`

Data for Exercise 9.36 and Example 9.8

`Randd`

A data frame/tibble with 12 observations on two variables

- rd
research and development expenditures (in million dollars)

- sales
sales (in million dollars)

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

```
plot(sales ~ rd, data = Randd)
model <- lm(sales ~ rd, data = Randd)
abline(model, col = "purple")
summary(model)
#>
#> Call:
#> lm(formula = sales ~ rd, data = Randd)
#>
#> Residuals:
#> Min 1Q Median 3Q Max
#> -14.3800 -10.5291 -0.8083 7.5896 28.9340
#>
#> Coefficients:
#> Estimate Std. Error t value Pr(>|t|)
#> (Intercept) 55.008 10.126 5.433 0.000288 ***
#> rd -6.816 2.626 -2.596 0.026690 *
#> ---
#> Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
#>
#> Residual standard error: 12.95 on 10 degrees of freedom
#> Multiple R-squared: 0.4025, Adjusted R-squared: 0.3428
#> F-statistic: 6.737 on 1 and 10 DF, p-value: 0.02669
#>
plot(model, which = 1)
rm(model)
```