Skip to contentA Practical Guide to Quantitative Finance Interviews
Table of Contents
- Chapter 1 General Principles1
- 1. Build a broad knowledge base1
- 2. Practice your interview skills1
- 3. Listen carefully2
- 4. Speak your mind2
- 5. Make reasonable assumptions2
- Chapter 2 Brain Teasers3
- 2.1 Problem Simplification3
- Screwy pirates3
- Tiger and sheep4
- 2.2 Logic Reasoning5
- River crossing5
- Birthday problem5
- Card game6
- Burning ropes7
- Defective ball7
- Trailing zeros9
- Horse race9
- Infinite sequence10
- 2.3 Thinking Out of the Box10
- Box packing10
- Calendar cubes11
- Door to offer12
- Message delivery13
- Last ball13
- Light switches14
- Quant salary15
- 2.4 Application of Symmetry15
- Coin piles15
- Mislabeled bags16
- Wise men17
- 2.5 Series Summation17
- Clock pieces18
- Missing integers18
- Counterfeit coins I19
- 2.6 The Pigeon Hole Principle20
- Matching socks21
- Handshakes21
- Have we met before?21
- Ants on a square22
- Counterfeit coins II22
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- 2.7 Modular Arithmetic23
- Prisoner problem24
- Division by 925
- Chameleon colors26
- 2.8 Math Induction27
- Coin split problem27
- Chocolate bar problem28
- Race track29
- 2.9 Proof by Contradiction31
- Irrational number31
- Rainbow hats31
- Chapter 3 Calculus and Linear Algebra33
- 3.1 Limits and Derivatives33
- Basics of derivatives33
- Maximum and minimum34
- L'Hospital's rule35
- 3.2 Integration36
- Basics of integration36
- Applications of integration38
- Expected value using integration40
- 3.3 Partial Derivatives and Multiple Integrals40
- 3.4 Important Calculus Methods41
- Taylor's series41
- Newton's method44
- Lagrange multipliers45
- 3.5 Ordinary Differential Equations46
- Separable differential equations47
- First-order linear differential equations47
- Homogeneous linear equations48
- Nonhomogeneous linear equations49
- 3.6 Linear Algebra50
- Vectors50
- QR decomposition52
- Determinant, eigenvalue and eigenvector53
- Positive semidefinite/definite matrix56
- LU decomposition and Cholesky decomposition57
- Chapter 4 Probability Theory59
- 4.1 Basic Probability Definitions and Set Operations59
- Coin toss game61
- Card game61
- Drunk passenger62
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- N points on a circle63
- 4.2 Combinatorial Analysis64
- Poker hands65
- Hopping rabbit66
- Screwy pirates 267
- Chess tournament68
- Application letters69
- Birthday problem71
- 100th digit71
- Cubic of integer72
- 4.3 Conditional Probability and Bayes' formula72
- Boys and girls73
- All-girl world?74
- Unfair coin74
- Fair probability from an unfair coin75
- Dart game75
- Birthday line76
- Dice order78
- Monty Hall problem78
- Amoeba population79
- Candies in a jar79
- Coin toss game80
- Russian roulette series81
- Aces82
- Gambler's ruin problem83
- Basketball scores84
- Cars on road85
- 4.4 Discrete and Continuous Distributions86
- Meeting probability88
- Probability of triangle89
- Property of Poisson process90
- Moments of normal distribution91
- 4.5 Expected Value, Variance & Covariance92
- Connecting noodles93
- Optimal hedge ratio94
- Dice game94
- Card game95
- Sum of random variables95
- Coupon collection97
- Joint default probability98
- 4.6 Order Statistics99
- Expected value of max and min99
- Correlation of max and min100
- Random ants102
- Chapter 5 Stochastic Process and Stochastic Calculus105
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- 5.1 Markov Chain105
- Gambler's ruin problem107
- Dice question108
- Coin triplets109
- Color balls113
- 5.2 Martingale and Random walk115
- Drunk man116
- Dice game117
- Ticket line117
- Coin sequence119
- 5.3 Dynamic Programming121
- Dynamic programming (DP) algorithm122
- Dice game123
- World series123
- Dynamic dice game126
- Dynamic card game127
- 5.4 Brownian Motion and Stochastic Calculus129
- Brownian motion129
- Stopping time/ first passage time131
- Ito's lemma135
- Chapter 6 Finance137
- 6.1. Option Pricing137
- Price direction of options137
- Put-call parity138
- American v.s. European options139
- Black-Scholes-Merton differential equation142
- Black-Scholes formula143
- 6.2. The Greeks149
- Delta149
- Gamma152
- Theta154
- Vega156
- 6.3. Option Portfolios and Exotic Options158
- Bull spread159
- Straddle159
- Binary options160
- Exchange options161
- 6.4. Other Finance Questions163
- Portfolio optimization163
- Value at risk164
- Duration and convexity165
- Forward and futures167
- Interest rate models168
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- Chapter 7 Algorithms and Numerical Methods171
- 7.1. Algorithms171
- Number swap172
- Unique elements173
- Horner's algorithm174
- Moving average174
- Sorting algorithm174
- Random permutation176
- Search algorithm177
- Fibonacci numbers179
- Maximum contiguous subarray180
- 7.2. The Power of Two182
- Power of 2?182
- Multiplication by 7182
- Probability simulation182
- Poisonous wine183
- 7.3 Numerical Methods184
- Monte Carlo simulation184
- Finite difference method189