##########
##
# Reading the data into R:

ff <- tempfile()
cat(file=ff, "
 A 85
 B 90
 C 93
 D 98
 A 82
 B 92
 C 94
 D 98
 A 83
 B 90
 C 96
 D 100
 A 88
 B 91
 C 95
 D 97
 A 89
 B 93
 C 96
 D 97
 A 92
 B 81
 C 94
 D 99
", sep=" ")

options(scipen=999) # suppressing scientific notation

insectdeaths <- read.table(ff, header=FALSE, col.names=c("insecticide", "dead")) 
  
# Note we could also save the data columns into a file and use a command such as:
# insectdeaths <- read.table(file = "z:/stat_516/filename.txt", header=FALSE, col.names = c("insecticide", "dead"))

attach(insectdeaths)

# Making "insecticide" a factor:

insecticide <- factor(insecticide)

# The data frame called insectdeaths is now created.
#########