Forecast of a total

The forecast of the sum of the next k periods, with intervals measured on totals in the backtest. Adding up the limits of each period would overstate the uncertainty of a total.

Usage

total_forecast(backtest, k, candidate = backtest$best)

Arguments

backtest

A result of backtest().

k

Periods added up.

candidate

A candidate name; by default the chosen one.

Value

A one-row tibble: periods, mean and the bounds of each interval.

Examples

bt <- backtest(AirPassengers, list(model_theta(), model_seasonal_naive()), origins = 24)
total_forecast(bt, 6)
#> # A tibble: 1 × 6
#>   periods  mean lower_80 upper_80 lower_95 upper_95
#>     <int> <dbl>    <dbl>    <dbl>    <dbl>    <dbl>
#> 1       6 2859.    2847.    3118.    2788.    3252.
colSums(bt$forecast[1:6, c("mean", "lower_80", "upper_80")])  # wider, and wrong
#>     mean lower_80 upper_80 
#> 2858.902 2762.949 3155.645