forecast (version 7.3)

forecast: Forecasting time series


forecast is a generic function for forecasting from time series or time series models. The function invokes particular methods which depend on the class of the first argument.

For example, the function forecast.Arima makes forecasts based on the results produced by arima.

The function forecast.ts makes forecasts using ets models (if the data are non-seasonal or the seasonal period is 12 or less) or stlf (if the seasonal period is 13 or more).


forecast(object,...) "forecast"(object, h = ifelse(frequency(object) > 1, 2 * frequency(object), 10) , level=c(80,95), fan=FALSE, robust=FALSE, lambda=NULL, find.frequency=FALSE, allow.multiplicative.trend=FALSE, ...)


a time series or time series model for which forecasts are required
Number of periods for forecasting
Confidence level for prediction intervals.
If TRUE, level is set to seq(51,99,by=3). This is suitable for fan plots.
If TRUE, the function is robust to missing values and outliers in object. This argument is only valid when object is of class ts.
Box-Cox transformation parameter.
If TRUE, the function determines the appropriate period, if the data is of unknown period.
If TRUE, then ETS models with multiplicative trends are allowed. Otherwise, only additive or no trend ETS models are permitted.
Additional arguments affecting the forecasts produced. forecast.ts passes these to forecast.ets or stlf depending on the frequency of the time series.


forecast".The function summary is used to obtain and print a summary of the results, while the function plot produces a plot of the forecasts and prediction intervals.The generic accessors functions fitted.values and residuals extract various useful features of the value returned by forecast$model.An object of class "forecast" is a list usually containing at least the following elements: is a list usually containing at least the following elements:

See Also

Other functions which return objects of class "forecast" are forecast.ets, forecast.Arima, forecast.HoltWinters, forecast.StructTS, meanf, rwf, splinef, thetaf, croston, ses, holt, hw.