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KahnemanMental model

Outside view

Reference class forecasting · Взгляд снаружи · Прогноз по референтному классу

Estimate by treating your case as a member of a reference class of similar past cases - not by reasoning from inside your specific story.

Plain explanation

The inside view tells you about your project. The outside view tells you about all projects that looked like yours. The outside view usually wins. It's also the view we instinctively skip - because the inside view feels uniquely informative.

Why it matters

Most forecasting failures come from refusing to look at the reference class. «Our case is different» is the most expensive sentence in planning.

Practical example

Building a SaaS startup: inside view says «we'll hit $10k MRR in 4 months». Outside view: most B2B SaaS take 12–24 months to $10k MRR; many never get there. Start there, then ask what makes your case different.

How to use
  1. 1Define the reference class. «What category does this case belong to?»
  2. 2Find 5+ examples. Note their actual outcomes, not their plans.
  3. 3Use the distribution as your prior. Then defensibly justify any deviation.
Read the original book

This part of the knowledge base is inspired by the book. Go to the Ukrainian edition to explore the concept in depth.

Source notes
  • · Методичка по Канеману - взгляд снаружи / reference class