Probability
Probability is the foundation of most quantitative interviews. This section teaches how to model uncertainty, condition on information, reason using symmetry, and recognize common probability structures.
Lessons · recommended order
- 1Sample Spaces and Basic RulesModel uncertainty with sample spaces and events, and use the complement and union rules to compute probabilities cleanly.Foundations8 min
- 2Conditional ProbabilityLearn to update probabilities on new information by restricting to a smaller sample space.Foundations9 min
- 3Bayes' TheoremInvert conditional probabilities to update beliefs about a hidden cause from an observed effect.Intermediate10 min
- 4IndependenceDistinguish true independence from mere lack of correlation, and verify it with the multiplication rule.Foundations7 min
- 5Symmetry and ExchangeabilityUse symmetry among exchangeable random variables to shortcut counting arguments.Intermediate7 min
- 6Geometric ProbabilityCompute probabilities for continuous uniform variables by comparing areas or volumes.Intermediate8 min
- 7Order StatisticsFind the distribution of the minimum, maximum, and general order statistics of independent random variables.Intermediate9 min