# ================
# THE CARS DATASET
# ================

data(swiss); swiss
dim(swiss)
?swiss

# ======================================
# Summary Statistic for Infant Mortality
# ======================================

x <- swiss$Infant.Mortality
mean(x)
median(x)
sd(x)
hist(x)
qqplot(x)

# Compute Quantiles
p <- c(10, 25, 50, 75, 80, 90)/100
quantile(x, probs=p)




# ==========================
# EXAMPLES ON ECDF          
# ==========================

## Computing ECDF
# ---------------
y <- round(rnorm(12),1); y
y[3] <- y[1]; y

Fn <- ecdf(y)
Fn
knots(Fn) # unique values (always less than 12!)
summary(Fn)
summary.stepfun(Fn)

### Plotting ECDF 
# -------------------
par(mfrow=c(3,1), mgp=c(1.5, 0.8,0), mar= rep(5, 4))
# Plot 1
plot.ecdf(y, main="ECDF of the Data")

require(graphics)
# Plot 2
plot(Fn, col.hor='red', add= TRUE, main="ECDF of Data")  #- plot method
abline(v=knots(Fn),lty=2,col='gray70')

## Plot 3: A Luxury one
plot(Fn, verticals=TRUE, col.points='blue', col.hor='red', 
        col.vert='bisque', main="ECDF of Data")