Track · 2:31 · Liner note
It Was a Holiday, Probably
Anomaly detection flags values that depart from the expected pattern, and a careful analysis checks ordinary explanations such as holidays, outages and campaigns before calling it a problem.
Sales dipped on a Tuesday and three people have a theory. It Was a Holiday, Probably is the first hypothesis worth checking in anomaly work: calendar effects, outages, campaigns and tracking changes explain more spikes and drops than anything exotic. Only after you rule them out does the anomaly earn a serious name.
Give your detector the calendar. Compare against the same weekday, flag known events and keep a short list of past false alarms. Then when something truly odd appears, you will have earned the right to be alarmed.