Analysis of the ToothGrowth Data Set

Simple Investigation

The ToothGrowth data set, which contains information on the tooth growth of guinea pigs after receiving Vitamin C either through a pill (Treatment = VC) or orange juice (Treatment = OJ), has 60 records.

An explorable table of the data is shown next.

library(DT)
datatable(ToothGrowth)

Simple Statistics of len

The tooth growth is recorded in the variable len. Its mean and standard deviation are shown below, followed by the five number summary.

Recall, the mean is simply \(\bar{x} = (\sum_i x_i)/n\) while the formula for standard deviation is shown below. \[s = \sqrt{\sum_{i=1}^n \frac{\left(x_i - \bar{x}\right)^2}{n-1}}\]

mean(ToothGrowth$len)
## [1] 18.81333
sqrt(var(ToothGrowth$len))
## [1] 7.649315
fivenum(ToothGrowth$len)
## [1]  4.20 12.55 19.25 25.35 33.90

About the Author

Include a picture you happen to have laying around, just for some practice. Bonus points if it’s cute and/or adorable!

Jonathan W. Duggins has a newfound obsession with quokkas.