One of my responsibilities is to do post-outage reporting to estimate how much money we lost. Right now I use Holt-Winters to give a forecast starting just before the outage began. I then estimate the loss to be the difference between the forecast and the data points that fall outside of the forecast's confidence interval.
Is this a statistically valid method? I chose Holt-Winters because I'm inexperienced and it's appealingly intuitive. Should I be looking at anomaly detection methods instead? Would they be able to tell me what "normal" would have been for the duration of the anomaly?
Is this a statistically valid method? I chose Holt-Winters because I'm inexperienced and it's appealingly intuitive. Should I be looking at anomaly detection methods instead? Would they be able to tell me what "normal" would have been for the duration of the anomaly?