Binomial distribution in R

We have one experiment with two possible results (success and fail) where the probability of success is Π. If we repeat n independent trials in the same conditions the variable...

x = number of success in n trails

follow a binomial distribution of n parameters and Π, and we write X ∈ Bin (n, Π). We can calculate mean and standard deviation too. The function dbinom in R calculate the odds of one variable follow binomial distribution. We can use..

dbinom(x, size, prob, log = FALSE)
pbinom(q, size, prob, lower.tail = TRUE, log.p = FALSE)
qbinom(p, size, prob, lower.tail = TRUE, log.p = FALSE)
rbinom(n, size, prob)

We show this with an example in R. 

n=8
prob=0.15
x=0:n
p=dbinom(x, size=n, prob=prob)
# p1=round(p,4)
names(p)=x
r=barplot(p,col='grey85',ylim=c(0,0.45),
          main=paste("Bin(n=8,p=",prob,")",sep=""))
text(r,p,round(p,2),pos=3,cex=0.7)

We get the Fig. 1 for one probability of 0.15, Fig. 2 for 0.25, Fig 3. for 0.50, Fig 4. for 0.75.

Figure 1. Binomiral distribution, prob 0.15

Figure 2. Binomiral distribution, prob 0.25

Figure 3. Binomiral distribution, prob 0.50

Figure 4. Binomiral distribution, prob 0.75