## Simple transformation of an environmental variable
range(env$slo)
# Log-transformation of the slope variable (y = ln(x))
# Compare histograms and boxplots of the raw and transformed values
par(mfrow = c(2, 2))
hist(env$slo,
col = "bisque",
right = FALSE
)
hist(log(env$slo),
col = "light green",
right = FALSE,
main = "Histogram of ln(env$slo)"
)
boxplot(env$slo,
col = "bisque",
main = "Boxplot of env$slo",
ylab = "env$slo"
)
boxplot(log(env$slo),
col = "light green",
main = "Boxplot of ln(env$slo)",
ylab = "log(env$slo)"
)
Histogram of env$slo
env$slo
Frequency
0
10
20
30
40
50
0 5 10 15 20 25 30
Histogram of ln(env$slo)
log(env$slo)
Frequency
-2 -1
0
1
2
3
4
0
2
4
6
8 10
0
10 20 30 40
Boxplot of env$slo
env$slo
-1 0
1
2
3
4
Boxplot of ln(env$slo)
log(env$slo)
Fig. 2.10 Histograms and boxplots of the untransformed (left) and log-transformed (right) “slope”
variable
2.2 Data Exploration
33