learning-from-outcomes

name	learning-from-outcomes
description	Turns past decisions into calibrated judgment - scoring old predictions against what happened, assigning credit for delayed results, and separating a bad decision from a good decision that lost. Use during a retrospective, postmortem, quarterly or monthly review, when reviewing decisions taken 30+ days ago, when attributing a result to a cause, or when someone claims to have called something.
license	MIT
metadata	{"source":"Kochenderfer, Wheeler & Wray, Algorithms for Decision Making (MIT Press, 2022), ch. 16-18, sec. 14.1"}
includes	["scripts/**","lib/**","examples/**"]

Learning from outcomes

Experience does not automatically produce judgment. Without a written prediction and a scoring step, a review produces a story in which the good outcomes were foreseen and the bad ones were unforeseeable. That story feels like learning and teaches nothing.

Three things make a review compound:

1. Score the predictions, not the outcomes.
2. Assign credit across time, because results arrive long after the decisions that caused them.
3. Replay old decisions deliberately, because recent experience otherwise overwrites older lessons entirely.

Workflow

- [ ] 1. Collect the predictions that came due
- [ ] 2. Score them
- [ ] 3. Separate decision quality from outcome quality
- [ ] 4. Assign credit for delayed results
- [ ] 5. Replay two old decisions that are not due
- [ ] 6. Update the priors that were wrong

1. Collect what came due

Pull every prediction from the decision log whose date has passed. Record the outcome as a plain binary before discussing anything, and before anyone explains why it happened.

If there is nothing to collect, the problem is upstream: decisions are being recorded without falsifiable predictions. Fix that in framing-decisions first; nothing here works without it.

2. Score them

Run the calculator. Do not compute these by hand.

node scripts/calc.js calibrate predictions.json

Brier decomposition, bin assignment and the base-rate benchmark are exactly the kind of arithmetic that comes out subtly wrong when done in prose, and a miscalibration verdict derived from a wrong number is worse than no verdict. Paste the real output into the review.

Input shape: examples/calibrate.json. Four numbers matter:

• Brier score - mean squared error of your probabilities. Lower is better.
• Always-base-rate - what you would have scored by ignoring specifics and always quoting the base rate. If your Brier score is not beating this, your judgment is adding nothing and the honest response is to quote base rates until it does.
• Verdict - overconfident, underconfident, or well calibrated.
• The bin table - of the things you called 80%, how many happened? Overconfidence concentrates in the high bins, which is where it does the most damage.

Twelve predictions is enough to see a pattern; five is not. Score quarterly at minimum, and keep the whole history rather than the current window.

3. Decision quality is not outcome quality

For each item, place it in the grid before discussing what to change:

	Good outcome	Bad outcome
Good process	earned it	bad luck - change nothing
Bad process	got away with it - fix anyway	the only cell that deserves blame

The two diagonal cells are where reviews go wrong. Punishing bad luck teaches people to avoid variance rather than to decide well. Rewarding a lucky call teaches the room to copy a bad process.

The decision record makes this decidable rather than rhetorical: if the record shows the advantage of second place was under a percent, the decision was a coin flip and the outcome carries almost no information about the process.

4. Assign credit for delayed results

Results arrive months after the decisions that caused them, and the discussion systematically credits whatever shipped most recently.

node scripts/calc.js credit result.json --lambda 0.7

Input shape: examples/credit.json. It decays credit by lambda per period back through the decisions that preceded the result. lambda = 0.7 is a reasonable default; use higher when effects are slow (SEO, brand, hiring) and lower when they are fast (a pricing change, an ad creative).

The output is a prompt for a better argument, not an answer. Its job is to put the six-month-old decision back on the table so someone has to argue about it explicitly rather than forget it.

5. Replay two old decisions

Pick two decisions from six or more months ago that are not due for review, and re-read them. Ask: does the reasoning still look right, knowing what you know now?

This is deliberate replay of old experience, and it exists to counter a specific failure: learning purely from recent events overwrites older lessons, so a system that only reviews what is current will confidently repeat a mistake it already learned about. Almost every long-running organisation has a lesson it has learned three times.

Keep a short list of replayed decisions so you rotate through the log rather than re-reading the same memorable ones.

6. Update the priors that were wrong

A lesson that does not change a number will not change a decision. State that, then act on it: the output of a review is not a list of lessons, it is a set of changed numbers, each written into a named file that will actually be read next time. "We should be more careful about X" survives one quarter. "The prior on X is 0.3, in runbooks/traffic-drops.md" survives indefinitely.

Name the destination for every number. A revised estimate with no home is a lesson wearing a number's clothes.

Numbers worth changing:

• The prior in a diagnosis set (tracking-beliefs)
• The reference-class estimate for how long something takes
• The likelihood assigned to a study method (valuing-information)
• Your calibration adjustment: if you are systematically overconfident at 80%, shade future 80% claims to 70% until the bin table says otherwise

A lesson that does not change a number will not change a decision. Write the number.

Output template

The review's output is a diff, not minutes. If something does not fit one of these sections, it did not need a meeting.

## Predictions that came due
| Prediction | stated P | outcome |
|---|---|---|

## Calibration
<paste calc calibrate: Brier, always-base-rate benchmark, verdict, bin table>
Skill versus base rate: <positive means judgment is adding value; negative means
quote base rates until it is not>

## Process versus outcome
| Decision | process | outcome | cell | action |
|---|---|---|---|---|
<spend the time on bad-luck and got-away-with-it; the other two need no action>

## Credit for delayed results
<paste calc credit, with the lambda used and why>

## Decisions replayed




| number | was | now | lives in | evidence |
|---|---|---|---|---|


  -> robustness matrix for 

Gotchas

• Score predictions, not outcomes. A review of outcomes is a review of luck.
• Never rewrite a prediction after the fact. Append the outcome. The value of the log is that it preserves what you actually believed, including the embarrassing parts.
• Overconfidence is the normal finding. If your 90% claims come true 70% of the time, that is typical, correctable, and worth more than any single lesson in the review.
• Watch the proxy metric. Any metric used as a target stops measuring what it measured. If activation rate became a goal and then rose without revenue following, the metric was optimised rather than the outcome. Check the downstream number.
• A result with one obvious cause is suspicious. Real results have several contributing decisions. If the room agrees instantly on a single cause, run the credit assignment and see who else is on the list.
• Do not review only failures. Successes with bad process are the most dangerous cell in the grid, because nobody wants to examine them and the process survives.
• Small samples justify simple explanations. Three data points do not support an elaborate causal story, however satisfying it is.
• Attribution windows lie. A 30-day attribution window credits whatever the customer touched last. The credit tool exists precisely because that is not causation.

Reference

• references/review-format.md - the monthly and quarterly review agendas, with time boxes
• references/calibration.md - reading the bin table, fixing overconfidence, how many predictions you need

Related skills

• framing-decisions writes the records this skill grades
• tracking-beliefs receives the corrected priors
• stress-testing-plans converts a past failure into a reusable scenario
• valuing-information receives the corrected likelihoods for study methods