Did the starter offer work?

HardSupercella/b testingbalance checkconversionz-testsample size· 160 XP (40 per step)

Mock interview. You're interviewing for a senior game data scientist job. The interviewer explains: "In February, new players were split into two groups. Most saw a cheap starter offer (offer_shown); some didn't (holdout). The team says the offer doubled paying players. Walk me through whether we can believe that."

Each player in the test has one row in experiments. A player converts if they made at least one purchase in their first 14 days (purchase_ts < install_date + 14).

Step 1: Are the groups comparable?

"Before looking at results, check the split. For each group, show the number of players and the share on iOS."

Expected output

  • Columns context, players, ios_share (a percentage rounded to 1 decimal); sorted by context

Example of the shape (made-up values):

context players ios_share
holdout 30 50.0

Hints, the later steps and the answer come with Pro.

Step 1 of 4

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