This is my search to recreate the data I am working on:
| makeresults
| eval data = "
2019-01-01 98.0;
2019-01-02 98.2;
2019-01-03 98.5;
2019-01-04 98.4;
2019-01-05 98.4;
2019-01-06 98.4;
2019-01-07 98.5;
2019-01-08 98.4;
2019-01-09 98.4;
2019-01-10 98.7;
2019-01-11 98.4;
2019-01-12 98.1;
2019-01-13 98.2;
2019-01-14 98.3;
2019-01-15 98.3;
2019-01-16 98.4;
2019-01-17 98.4;
2019-01-18 98.0;
2019-01-19 97.7;
2019-01-20 98.3;
2019-01-21 98.3;
2019-01-22 98.3;
2019-01-23 98.4;
2019-01-24 98.3;
2019-01-25 98.4;
2019-01-26 98.1;
2019-01-27 98.0;
2019-01-28 98.4;
2019-01-29 98.4;
2019-01-30 98.7;
2019-01-31 98.4;
"
| makemv delim=";" data
| mvexpand data
| rex field=data "(?<Date>\d+-\d+-\d+)\s+(?<kpi1>\d+(\.\d+)?)"
| fields + Date kpi1 | fields - _time
| search kpi1=*
| rename Date as _time
If I add | outlier action=remove uselower=true
the value on 19th Jan will be removed.
What I am trying to understand is why it is removed. I deally I would like to see the maths behind it, and hopefully that will explain it to me. I have raised a similar/related question here. What I would like to do is be able to draw the line on where the cutoff point is the graph.