Exercise

Confidence Intervals for Forecast

Your forecast object forecast_MET_t not only has the forecast, but also margin of error calculations for the forecast called confidence intervals. These confidence intervals show us a wiggle room on our forecasts since no forecast is ever perfect.

The forecast was stored as the object forecast_MET_t$mean. The upper and lower limit of this interval is stored similarly. The second column of the upper confidence interval is the 95% confidence interval and can be accessed via forecast_MET_t$upper[,2]. To get the lower limit replace the word upper with lower.

Instructions

100 XP
  • Convert both the upper and lower 95% confidence limits to xts objects upper and lower. Your date index is stored as for_dates.
  • Add these to the plot of the forecast and the validation data set.