The expected value calculation does not have knowledge of the data range of the series

[nnoradie]

System information

• OS version/distro: .Net 4.8
• .NET Version (eg., dotnet --info): ML.Net 1.5.2

Issue

• What did you do?
  Detected anomalies on dataset with only non-negative values and saw a negative expected value range.

• What happened?
  

• What did you expect?
  The expected value range to be non-negative.

Source code / logs

Please paste or attach the code or logs or traces that would be helpful to diagnose the issue you are reporting.

Csv and email correspondence
covid19_deaths.zip

The options set for anomaly detection:
var options = new SrCnnEntireAnomalyDetectorOptions()
{
Threshold = 0.05,
BatchSize = -1, // not set, so we are using the default, is that -1?
Sensitivity = 75.0,
DetectMode = SrCnnDetectMode.AnomalyAndMargin,
Period = -1,
DeseasonalityMode = SrCnnDeseasonalityMode.Median // the period is -1, so I assume deseasonalize is not applied?
};

[nnoradie]

Fixed by increasing ad threshold to 0.1