# coinflips.R # Example 8.9 # fluctuations in coin tossing trials <- 10000 simlist <- numeric(trials) t <- 0.95 for(i in 1:trials) {rw <- c(0,cumsum(sample(c(-1,1),10000, replace=T))) simlist[i] <- if (0 == length(which(rw[(10000*t):10000]==0))) 1 else 0 } mean(simlist) trials <- 10000 simlist <- numeric(trials) for(i in 1:trials) { rw <- c(0,cumsum(sample(c(-1,1),(trials-1),replace=T))) simlist[i] <- tail(which(rw==0),1) } mean(simlist) hist(simlist,xlab="",ylab="Counts",main="")