Cognitive biases and judgment · 3/6
Availability: does memorable mean common?
Replace recalled cases with comparisons specifying time, scope and denominators.
About 15–20 minutes. The following cases are fictional.
Record your first judgment
After seeing three phone-battery failure videos, you rank that model worst. Videos might repeat one event, and you do not know how many units are used.
Understand the judgment process
People may judge frequency by how readily events come to mind, sometimes producing error. Vivid cases can suggest what to investigate but do not directly estimate probability.
Repeated exposure is not repeated occurrence. Define the event, observation window, reporting channel and exposure. More cases may reflect more users.
Records may undercount events. A missing denominator is not a reason to dismiss an individual incident; investigate it while withholding a population ranking.
Checks you can perform
- Turn “always happens” into a defined question about a time and population.
- Check whether recalled cases are independent.
- Seek consistent counts and denominators, checking reporting and use differences.
- Record incident verification separately from frequency comparability.
Guided practice
One reporting system records 20 reports among 10,000 active A units and 6 among 1,000 active B units in the same year. Describe report rates and one limitation.
Explore the explanation
A has 0.2% and B 0.6%. A has more reports but a lower reported rate using these denominators. These are not established failure probabilities: check duplicate reports, usage duration, event definitions and underreporting.
Apply it in a new context
A colleague remembers two remote-work coordination failures but none in the office. How would you test “remote is always worse”?
Compare after attempting
Define failures and a period, then gather successes and failures for comparable tasks under both arrangements, not just memorable incidents. Check task and staff differences. Unrecorded failures are not necessarily absent.
Preserve a revision record
Do not ignore rare severe events. Decisions also depend on harm and feasible precautions.
Check whether you supplied inspectable evidence, a feasible next step and revision conditions. Revealing an answer is not mastery.
Source and scope
Tversky & Kahneman (1974), Judgment under Uncertainty
The source provides conceptual or methodological background. Cases, steps and exercises are authored here; they are not the original experiment or evidence of this course’s effectiveness.
Completion is a personal record, not proof of mastery or certification.