xmp06.13 {Devore5} | R Documentation |
The xmp06.13
data frame has 420 rows and 1 columns of the
number of goals pre game scored by National Hockey League teams
during the 1966-1967 season.
This data frame contains the following columns:
Devore, J. L. (2000) Probability and Statistics for Engineering and the Sciences (5th ed), Duxbury
Reep, C. and Pollard, R. and Benjamin, B. (1971), ``Skill and chance in ball games'', Journal of the Royal Statistical Society, Series A, General, 134, 623629
data(xmp06.13) attach(xmp06.13) table(goals) # compare to frequency table on p. 267 hist(goals, breaks = 0:12 - 0.5, las = 1, col = "lightgray") negBinom.MoM <- function(x) { ## method of moments estimates for negative binomial distribution xbar <- mean(x) mnSqDev <- mean((x - xbar)^2) c(p = xbar/mnSqDev, r = xbar^2/(mnSqDev - xbar)) } print(goals.MoM <- negBinom.MoM(goals)) ## MLE's optim(goals.MoM, function(x) -sum(dnbinom(goals, p = x[1], size = x[2], log = TRUE))) ## would have been better to use a transformation of p detach()