pub fn www_usage() -> Result<DataFrame, PolarsError>Expand description
§Internet Usage per Minute
§Description:
A time series of the numbers of users connected to the Internet through a server every minute.
§Usage:
WWWusage
§Format:
A time series of length 100.
§Source:
Durbin, J. and Koopman, S. J. (2001). Time Series Analysis by State Space Methods. Oxford University Press.
§References:
Makridakis, S., Wheelwright, S. C. and Hyndman, R. J. (1998). Forecasting: Methods and Applications. Wiley.
§Examples:
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)