Info on Alert Thresholds: 99.9% of what?

[MarkVictoria]

What does 99.9% threshold mean?  Is it 99.9% of a standard deviation and above? 

I'm using the 99.9% as an example. There are other thresholds 

[fhusain · Accepted solution]

The % thresholds are standard deviations. For example, 95% = 2 standard deviations and 99% = 3 standard deviations. Depending on the time granularity you choose, different models are used to calculate how far away (how many standard deviations) each data point is from the norm. If you set a lower threshold (such as 90%), you will get more anomalies than if you set a higher threshold (99%). 99.75% & 99.99% thresholds were introduced specifically for the hourly granularity so that it wouldn’t trigger as many anomalies.

You can find more info here - https://experienceleague.adobe.com/en/docs/analytics/components/alerts/intellligent-alerts#:~:text=a...

[MarkVictoria]

Thank you, that's exactly what I was hoping for.