Chapter 13 · Product Analyst
Appendix B: quick-reference glossary
~4 min read
| Term | Meaning |
|---|---|
| AARRR | Acquisition, Activation, Retention, Revenue, Referral. |
| Aha moment | The early action that best predicts long-term retention. |
| Activation | The moment a new user first experiences core value. |
| CAC / LTV | Cost to acquire / lifetime margin; LTV:CAC ratio gauges growth health. |
| Cohort | A group of users sharing a start point, tracked over time. |
| CUPED | Variance-reduction technique using pre-experiment data. |
| Guardrail metric | A metric that must not regress even if the primary improves. |
| HEART | Happiness, Engagement, Adoption, Retention, Task-success. |
| MDE | Minimum Detectable Effect, smallest reliably detectable effect. |
| North Star | The single metric best capturing the value a product delivers. |
| p-value | Probability of a result this extreme if the null were true. |
| Power | Probability a test detects a real effect; typically 80%. |
| Retention | Share of a cohort still active after N days. |
| Simpson's paradox | A trend in aggregate that reverses within every segment. |
| Stickiness | DAU/MAU, how habitually monthly users return. |
| Vanity metric | A number that rises and looks good but informs no decision. |
Get the next chapter and weekly interview tips by email
One short email per week. Skim in a minute. Unsubscribe anytime.