#  world cup soccer 1994 
#  Edps 587
#  C.J.Anderson
#
#  Read in data
#  Plots histogram
#  Overlay Poisson distribution
#

# create data
n.goals <- seq(from=0,to=7)
counts <- c(20,29,16,3,1,0,1,0)

mu <- weighted.mean(n.goals,counts)

# Quick look at data
barplot(counts,
        main="Goals Scored in 1st Round of 1994 World Cup",
		xlab="Number of Goals Scored",
		names.arg = c("0","1","2","3","4","5","6,","7+"),
		col="cyan"
             )
			 
			 
# To overlay predicted Poisson	
mu <- weighted.mean(n.goals,counts)
d.poisson <- dpois(n.goals,mu)
pred.goals <- d.poisson*sum(counts)


# Data and predicted: version 1
plot(n.goals,counts, type="h",
        main="Goals Scored in 1st Round of 1994 World Cup",
		xlab="Number of Goals Scored",
		col="cyan"
             )
lines(n.goals,pred.goals,type="p")			 
text(6,28,"mu=1.143")
text(6,26.5,"total=70")

# Data and predicted: version 2
barplot(counts,
        main="Goals Scored in 1st Round of 1994 World Cup",
		xlab="Number of Goals Scored",
		names.arg = c("0","1","2","3","4","5","6,","7+"),
		col="cyan"
             )
n.goals0 <- c(0.75, 1.9, 3.15, 4.25, 5.5, 6.75, 8.0 , 9.25)   # to center points of number
lines(n.goals0,pred.goals,type="b")
text(8.25,28,"mu=1.143")			 
text(8.25,26.5,"total=70")