2 Motivation

2.1 A matter of life and death

The author introduces the chapter with an anecdote about the Space Shuttle the Challenger built in 1986
It is infamous for exploding soonafter launch, killing all astronauts aboard
An investigation of disaster found that these o-rings, which would have otherwise prevented fuel leaks, failed
The investigation found that their failure was the result of colder than typical temperatures on the day of the launch, causing the o-rings to become brittle and allow fuel to leak
Data from the investigation can be found in the package ‘faraway’

install.packages("faraway",repos = "https://cran.us.r-project.org")
install.packages("ggplot2",repos = "https://cran.us.r-project.org")

library(faraway)
library(ggplot2)

head(orings)

Plot the data from the orings dataset:

fig2_2 <- ggplot(orings, aes(x = temp, y = damage)) + geom_point() + theme_bw()
fig2_2

The question that the data pose is if the number of leaks is associated with temperature. But NASA scientists and engineers did not draw up a graph like this to ask the question.

2.2 Summary: statistics

The Challenger o-rings data is too complex for now, but the author will start with data from Charles Darwin

2.3 Summary: R

1 Introduction

3 Description