🪵🪄 Log transforms

🪵🪄 Log transforms

We’re adding the ability to log-transform sum and count metrics, and measure the average change to unit-level logged values.

Log Transforms are useful when you want to understand if user behavior has generally changed. If a metric is very head-driven, even with winsorization and CUPED the metric movement will generally driven by power users.

Logs are multiplicative, so a user going from spending $1.00 to spending $1.10 is the same “metric lift” as another going from $100 to $110. This means that what they measure is closer to shifts in relative distribution, rather than topline value.

Because of this divorce from “business value,” log metrics are usually not good evaluation criteria for ship decisions, but alongside evaluation metrics, they can easily provide rich context on the change in the distribution of your population.

By default, the transform is the Natural Log, but you can specify a custom base if desired.

Learn more in our documentation.