WWWusage {datasets} | R Documentation |
A time series of the numbers of users connected to the Internet through a server every minute.
WWWusage
A time series of length 100.
Durbin, J. and Koopman, S. J. (2001). Time Series Analysis by State Space Methods. Oxford University Press.
Makridakis, S., Wheelwright, S. C. and Hyndman, R. J. (1998). Forecasting: Methods and Applications. Wiley.
require(graphics)
work <- diff(WWWusage)
par(mfrow = c(2, 1)); plot(WWWusage); plot(work)
## Not run:
require(stats)
aics <- matrix(, 6, 6, dimnames = list(p = 0:5, q = 0:5))
for(q in 1:5) aics[1, 1+q] <- arima(WWWusage, c(0, 1, q),
optim.control = list(maxit = 500))$aic
for(p in 1:5)
for(q in 0:5) aics[1+p, 1+q] <- arima(WWWusage, c(p, 1, q),
optim.control = list(maxit = 500))$aic
round(aics - min(aics, na.rm = TRUE), 2)
## End(Not run)