Behavioral & Communication · core
Decision Making
Tradeoffs under uncertainty.
Mental model
Decisions are bets you make with incomplete information. Judge them by the reasoning at the time, not the outcome. Good decisions name in advance what evidence would tell you you are wrong.
How to study Decision Making
Begin by restating the mental model in your own words, then connect it to a concrete system you have built or operated. Name the mechanism, the constraint it addresses, and the trade-off it introduces. Use Decision-making (Wikipedia), STAR interview method (Wikipedia) to check details, but close the source before writing your explanation. Retrieval is the learning step; rereading is only preparation.
Next, compare Decision Making with the neighboring concepts in its roadmap. Ask what changes in correctness, latency, resource use, operability, and failure recovery. Complete STAR: tough decision and preserve the command, input, output, and one failed attempt as evidence. Finish by explaining the idea without jargon to someone who has not studied the track.
Proof of understanding
- Explain the mechanism from first principles and identify the state it reads or changes.
- Give one situation where the concept is the right choice and one where it is not.
- Predict a realistic failure mode before running the drill, then compare the prediction with evidence.
- Connect the result to a roadmap or build artifact instead of treating the concept as isolated trivia.
Learn from primary sources
Practice and explain it back
STAR: tough decision
Write a STAR about a hard call you made with incomplete information. Show your reasoning and what you tracked to know if you were wrong.
Expected evidence: starStory() returns { situation, task, action, result, metric: { name, unit, before, after }, earlyWarningSignal (how you would have known sooner) }. The checker enforces structure only: four distinct sections of 20+ words, action the longest, 150+ words total, before ≠ after, and the result section must name the metric and state its after value. Aim for 250-350 words — that is the interview bar, not the checker’s.
Open the interactive drill →Review prompts
- What separates a bad decision from a bad outcome, and what do you have to write down to tell them apart later?
Build evidence
Use a roadmap capstone to turn this concept into working evidence.
Prerequisites
None assigned yet.
Related concepts
None assigned yet.