I did a change on my webpage on a given date. Now a want to measure if there is a significant impact on the usage due to the change. How can I do a sampled t-test in Application Insights? Splitting the time series data on a given date than comparing the two sets?
1 Answers
2
votes
In the KQL there is a built-in function for calculating Welch's t-test: welch_test().
Given a table T with a metric m and a change date d, you can calculate the test by aggregating the metric before and after the change:
T
| summarize m1 = avgif(m, Timestamp < d),
v1 = varianceif(m, Timestamp < d),
c1 = countif(Timestamp < d),
m2 = avgif(m, Timestamp > d),
v2 = varianceif(m, Timestamp > d),
c2 = countif(Timestamp > d)
| extend pValue=welch_test(m1,v1,c1,m2,v2,c2)