Base Rates

How often does this kind of thing work, before you consider this particular case?

The idea

Start with how often similar events occur before focusing on a story.

In the real world

Most new products struggle despite a compelling founder.

Going deeper

A base rate is how often something happens across similar cases, and it is the correct starting point before anything specific is considered. The specifics should then move that estimate, rather than replace it.

What makes this hard is that vivid detail is exactly what causes the base rate to be discarded. An articulate founder, a compelling deck and a real market are all genuine evidence, and none of them changes the underlying rate very much. The discipline is to establish the rate first, in writing, because doing it afterwards means fitting the number to a conclusion already reached.

Where it stops applying

Base rates can be wrong or drawn from a badly chosen reference class, and picking which class you belong to is itself a judgement. A rate from a genuinely different population is not a starting point, it is a distraction.

Why it matters

It gives you a starting estimate that a compelling story cannot easily move.

Try this today

Find a relevant reference class.

Test yourself

A founder is articulate, the deck is excellent, and the market is real. You feel this one will work. What should you establish first?

Show the answer

How often companies of this type at this stage succeed. That rate is the starting point; the specifics of this case should adjust it, not replace it. A vivid story is exactly the thing most likely to make you skip the step.

Learn this in the feed Answering from memory, then again days later, is what makes it stick.

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