Split Decision

A medium Data Modeling interview practice problem on DataDriven. Write and execute real data modeling code with instant grading.

Domain

Data Modeling

Difficulty

medium

Seniority

L5

Problem

We run dozens of product experiments at once on our consumer app, and each user who enters an experiment is locked to a single variant for its duration: either the control or one of the treatment groups. Analysts measure lift by comparing what users in each variant did after they were enrolled, joining their assignments back to our existing event log. Design the data model so a user can never land in two variants of the same experiment and so only post-enrollment behavior counts toward a variant's metrics.

Summary

One user, one experiment, one variant. No exceptions.

Practice This Problem

Solve this Data Modeling problem with real code execution. DataDriven runs your solution and grades it automatically.