Knowledge Check

Stratification evidence

While reviewing experimentation randomization, country strongly predicts conversion. Which action fixes it, and which check proves it worked?

What this task practices

Stratification evidence is a knowledge check interview exercise that trains prompt interpretation, explicit assumptions, a concrete response, and a clear explanation of tradeoffs. The catalog marks it as hard difficulty. It focuses on Experimentation Randomization, Stratification. The signed-in workspace provides the tools for the round and evaluates the attempt against task-specific criteria. Reference solutions, hidden checks, evaluator instructions, and candidate work remain private.