Random Variables Questions for Market Maker Interviews
A market maker round does not test random variables the way a textbook does. This set is the overlap - the random variables questions that actually turn up in this format.
48 questions, all free to practise. The split is 4 easy, 22 medium, 22 hard.
- Beating a product of uniformsEasyProbabilityRandom VariablesView →
- Beating three othersEasyProbabilityRandom VariablesView →
- Six heads from a random biased coinEasyConditional Probability & ExpectationRandom VariablesView →
- Whether either bus comes soonEasyProbabilityRandom VariablesView →
- A convexity gap by JensenMediumRandom VariablesExpected ValueView →
- A divergent reciprocal expectationMediumRandom VariablesCalculusView →
- A low medianMediumProbabilityRandom VariablesView →
- Best linear blend of two estimatesMediumRandom VariablesStatisticsView →
- Density of a uniform squaredMediumRandom VariablesCalculusView →
- Expectation of e raised to a normalMediumRandom VariablesExpected ValueView →
- Expected flips for HHMediumRandom VariablesExpected ValueView →
- First head strictly soonerMediumProbabilityRandom VariablesView →
- Four fives before the first sixMediumProbabilityRandom VariablesView →
- Four times as long to the first headMediumProbabilityRandom VariablesView →
- How many trials to poll a proportionMediumRandom VariablesStatisticsView →
- Matching floors of a logarithmMediumProbabilityRandom VariablesView →
- Mean over variance of a nested uniformMediumProbabilityRandom VariablesView →
- Median of a linear densityMediumRandom VariablesCalculusView →
- Memoryless waitingMediumConditional Probability & ExpectationRandom VariablesView →
- Optimally pooling two estimatorsMediumRandom VariablesStatisticsView →
- Order statistics of two uniformsMediumRandom VariablesStatisticsView →
- Ratio of partial sumsMediumRandom VariablesExpected ValueView →
- Remaining life of a memoryless partMediumRandom VariablesView →
- Sampling an exponential from a uniformMediumRandom VariablesProgramming & DSAView →
- The larger die shows a 4 - what about the smaller?MediumProbabilityRandom VariablesView →
- The probability integral transformMediumRandom VariablesStatisticsView →
- A small sub-triangleHardProbabilityRandom VariablesView →
- A three-way race to the first headHardProbabilityRandom VariablesView →
- Best-of-seven underdogHardProbabilityRandom VariablesView →
- Correlation of min and maxHardProbabilityRandom VariablesView →
- Counting fives before a four and a sixHardProbabilityRandom VariablesView →
- Draws to beat a hidden uniformHardRandom VariablesExpected ValueView →
- Draws to pass a log thresholdHardProbabilityRandom VariablesView →
- Draws to pass twoHardProbabilityRandom VariablesView →
- HTH before HHTHardProbabilityRandom VariablesView →
- Overshoot past oneHardProbabilityRandom VariablesView →
- Penalty kicks with a shifting rateHardProbabilityRandom VariablesView →
- Ratio of two normalsHardRandom VariablesStatisticsView →
- Shortest of three piecesHardProbabilityRandom VariablesView →
- Six pieces, none past a halfHardProbabilityRandom VariablesView →
- Smallest possible MGF valueHardRandom VariablesStatisticsView →
- Spread of a multinomial count gapHardRandom VariablesStatisticsView →
- The decreasing run of uniformsHardRandom VariablesExpected ValueView →
- Three first-heads in non-decreasing orderHardProbabilityRandom VariablesView →
- Two random segments overlappingHardProbabilityRandom VariablesView →
- Uniforms summing past 1HardRandom VariablesExpected ValueView →
- When a uniform ratio rounds to a squareHardProbabilityRandom VariablesView →
- When the extremes sum above oneHardProbabilityRandom VariablesView →
Widen the search
This set is a slice of two larger ones. If it is too narrow, start here instead:
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