Decide Before You're Certain: Bayesian Thinking for Product Managers

By Adrian Keller

Product managers make bets every day.

You rarely have enough data. User research is messy. A/B tests are underpowered. Stakeholders disagree. And yet you still have to decide.

Decide Before You're Certain gives product managers a practical Bayesian framework for making better decisions under uncertainty. Instead of pretending the data speaks for itself, you will learn how to combine prior knowledge, new evidence, and real-world consequences to make decisions you can defend.

Through concrete product examples, simple math, and spreadsheet-friendly tools, Adrian Keller shows how to:

- turn intuition into explicit priors
- interpret small-sample evidence without overreacting
- read A/B tests beyond p-values
- decide when more data is worth waiting for
- prioritize uncertain product bets
- forecast roadmaps with ranges instead of false precision
- align teams around thresholds, tradeoffs, and learning

The book follows one practical loop:
Prior -> Evidence -> Posterior -> Stakes -> Decision -> Outcome -> New Prior.

The goal is not perfect prediction. The goal is better judgment.

A practical guide for product managers, founders, product analysts, and decision-makers who need to act before certainty arrives.

• Format: Paperback
• Language: English
• ISBN: B0HKCDDR53
• ISBN13: 9798175491754
• Release Date: September 2026
• Publisher: Independently Published
• Length: 148 Pages
• Weight: 0.46 lbs.
• Dimensions: 0.3" x 6.0" x 9.0"