x = c(1,2,3,4,5,6,7,8,9,10)
d.x = diff(x); d.x
## 1 1 1 1 1 1 1 1 1
mean(d.x)
## 1

(max(x) - min(x))/(length(x)-1)
## 1

y = runif(1000)        # generate 1000 obs from UNIF(0,1)
d.y = diff(sort(y))    # 999 interarrival times
mean(d.y)
## 0.0009988142        # aprx mean interarrival time, exact = 0.001