# Data Drift Report

Drift Report service creates a statistical report based on a comparison of training and production data distributions. It compares these two sets of data by a set of statistical tests and finds deviations.

![](https://2921833647-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MESaD8WY3ggQLtBByXl%2Fsync%2Fe8dd03f317387790d4443f3d31f45c5782953f23.png?generation=1603095673865718\&alt=media)

Drift report uses multiple different tests with p=.95 for different features:

**Numerical** features:

* Levene's test with a trimmed mean 
* Welch's t-test
* Mood's test
* Kolmogorov–Smirnov test

**Categorical** features:

* Chi-Square test
* Unseen categories

## Supported Models

Right now Drift Report feature works only for Models with numerical scalar fields.