Head of Analytics

Iris Vandal

Spent nine years building measurement models for subscription products before joining Ether.

Biography

Iris leads the analytics practice at Ether. Before that she spent nine years inside subscription businesses, most of it arguing that the retention number on the slide was not the retention number in the warehouse.

She writes here about measurement models: how to pick the handful of metrics that decide something, how to define them so two teams reach the same figure, and how to tell the difference between a trend and a reporting artefact.

Entries by this author.

14 Aug 2026 Measurement

Your activation metric is probably measuring signup friction

Most activation definitions capture how hard it was to get through onboarding, not whether the product landed. Here is how to tell the two apart.

Iris Vandal

19 Jun 2026 Retention

A cohort chart that separates, or no cohort chart at all

If your retention curves sit on top of each other, the chart is decoration. Three cuts that tend to produce real separation.

Iris Vandal