Question

Use R to do the procedures listed below.

Load your data set on the R compiler as vector x

1. Determine the mean, variance, and standard deviation of x.
2. Plot the values of x on the vertical axis against the index values (i.e. the observation number: 1, 2, ... n) on the horizontal axis.
3. Add to your plot a horizontal line representing the mean of x colored red.
4. Annotate your R script to document each procedure and to interpret your results (e.g. "# This calculates the mean of x")

save the full R code

Data set: %IncChg 27.2 25.2 25.7 80.9 26.9 20.2 25.4 26.9 26.4 26.3 27.5 38.2 20.9 31.3 23.5 26 35.8 30.9 15.5 24.8 29.4 11.7 32.6 32.2 27.6 27.5 28.7 28 15.6 20 21.8 18.4 27.3 13.4 14.7 21.6 26.8 20.9 32.7 29.3 21.4 29 7.2 25.7 25.5 39.8 26.6 24.2 33.5 16 29.4 26.8 32 24.7 24.2 29.8 25.8 18.2 26 26.2 21.7 27 23.7 28 11.2 26.2 21.6 23.7 28.3 34.1 40.8 16 50.5 54.1 3.3 23.5 10.1 14.8

Answer 1

x=c(27.2,25.2,25.7,80.9,26.9,20.2,25.4,26.9,26.4,26.3,27.5,38.2,20.9,31.3,23.5,26,35.8,30.9,15.5,24.8,29.4,11.7,32.6,32.2,27.6,27.5,28.7,28,15.6,20,21.8,18.4,27.3,13.4,14.7,21.6,26.8,20.9,32.7,29.3,21.4,29,7.2,25.7,25.5,39.8,26.6,24.2,33.5,16,29.4,26.8,32,24.7,24.2,29.8,25.8,18.2,26,26.2,21.7,27,23.7,28,11.2,26.2,21.6,23.7,28.3,34.1,40.8,16,50.5,54.1,3.3,23.5,10.1,14.8)

mean(x)#mean

sd(x)#standard deviation

var(x)#variance
plot(1:length(x),x, xlab="index", ylab="x")
abline(h=mean(x), col="red")