Judgment & Evidence01
Count the missing denominator
A percentage describes a part relative to a specified whole.
3 min · 2 questions
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Judgment & Evidence
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Judgment & Evidence02
Sample the people who are absent
A sample can represent its respondents accurately while misrepresenting the population of interest.
3 min · 2 questions
Judgment & Evidence03
Distinguish independence from exclusion
Independent events do not change one another’s probabilities.
3 min · 2 questions
Judgment & Evidence04
Update with the base rate
A conditional probability depends on what is already known.
3 min · 2 questions
Judgment & Evidence05
State what would change your mind
A hypothesis becomes easier to investigate when it names an observable contrast.
3 min · 2 questions
Judgment & Evidence06
Read an interval as a procedure
An estimate summarizes a sample, while an interval expresses uncertainty under a statistical model.
3 min · 2 questions
Judgment & Evidence07
Separate a model from its residuals
A straight-line model represents a relationship with an intercept and slope.
3 min · 2 questions
Judgment & Evidence08
Test an argument’s structure
Deductive validity concerns whether a conclusion must follow if the premises are true.
3 min · 2 questions
Judgment & Evidence09
Keep a forecast scorecard
A forecast should specify an event, a deadline, and an assessment made before the outcome is known.
3 min · 2 questions
Judgment & Evidence10
Distinguish facts from decision thresholds
Evidence estimates what may be true; a decision rule determines what action follows.
3 min · 2 questions
Economics & Incentives11
Price the next best alternative
Opportunity cost is the value of the best alternative forgone when choosing an action.
3 min · 2 questions
Economics & Incentives12
Decide at the margin
Marginal analysis compares the additional benefit and additional cost of a small change.
3 min · 2 questions
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