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Guide
Derivatives pricing0 / 17
01Forwards, calls and puts02Combining positions03Arbitrage and the forward price04Put–call parity05The one-step binomial model06Risk-neutral probabilities07Multi-step trees and backward induction08American options and early exercise09Delta and hedging10Geometric Brownian motion11The Black–Scholes formula12The Greeks: gamma, vega, theta and rho13Options on dividend-paying stocks, indices, currencies and futures14Implied volatility and the volatility smile15Stochastic volatility and the Heston model16Static replication: Breeden–Litzenberger and Carr–Madan17Exotic options: barriers, Asians and digitals
Portfolio & risk0 / 12
01Returns and volatility02Diversification and correlation03The efficient frontier and the capital market line04Risk aversion and the optimal complete portfolio05CAPM, beta and the security market line06Performance measures: Sharpe, Treynor, Jensen and information ratio07Factor models and systematic risk08The Fama–French factor models09Value at Risk and expected shortfall10Systemic risk and contagion11Portfolio constraints and the no-short-sales frontier12Estimating expected returns and covariances
Fixed income0 / 10
01Bond prices and yields02Duration and convexity03Immunization and duration matching04Spot rates, forward rates and the yield curve05Non-parallel curve moves and key-rate durations06Bond futures and the cheapest-to-deliver07Interest rate swaps08Callable bonds and negative convexity09Credit risk: default probabilities and credit spreads10Real rates, inflation and inflation-linked bonds
Corporate finance0 / 10
01Interest, compounding and discounting02Annuities, perpetuities and loan amortization03Net present value and internal rate of return04Project risk: sensitivity, scenarios and Monte Carlo NPV05The weighted average cost of capital06Capital structure and the Modigliani–Miller theorems07Dividends, payout policy and the dividend discount model08Discounted cash flow valuation09Relative valuation with multiples10Real options: the value of flexibility
Probability and measure0 / 13
01Measuring the size of sets02σ-algebras and Borel sets03Lebesgue measure and null sets04Measurable functions05The Lebesgue integral06Convergence theorems07Probability spaces and Kolmogorov's axioms08Random variables and their distributions09Expectation, variance and inequalities10Independence and product measures11Modes of convergence and the law of large numbers12Conditional probability and conditional expectation13Measure theory in option pricing
Stochastic models0 / 17
01Random walks and Brownian motion02The law of large numbers and the central limit theorem03Probability spaces, σ-algebras and random variables04Filtrations, adapted processes and stopping times05Conditional expectation and martingales06Properties of Brownian motion07The reflection principle and first passage times08The Brownian bridge09The Itô integral10Itô's lemma11Kolmogorov equations and the Feynman–Kac formula12Change of measure and Girsanov's theorem13Monte Carlo option pricing14Simulating SDEs: the Euler–Maruyama scheme15Correlated Brownian motions and multi-asset models16Mean reversion: Ornstein–Uhlenbeck and Vasicek17Jumps and the Merton jump-diffusion model
Market microstructure0 / 11
01Market makers and liquidity02The limit order book03Queue position and fill probability04Adverse selection and informed trading05The Glosten–Milgrom model06Measuring and decomposing the bid–ask spread07Informed trading and Kyle's lambda08Price impact and optimal execution09Inventory risk and quote skewing10Optimal quoting: the Avellaneda–Stoikov model11Market making profit and loss attribution
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Guide · Track 05

Probability and measure

Measure theory and probability from the ground up: measures, σ-algebras, Lebesgue measure and the Lebesgue integral, convergence theorems, then probability spaces, distributions, expectation, independence, limit theorems and conditioning, and finally how they meet in option pricing.

Your progress0 of 13 read
Up next · Lesson 01Measuring the size of sets

13 lessons, in order

Each builds on the one before

  1. 01Measuring the size of setsWhat counting, length, area and mass have in common: the rules of a measure, why additivity must be countable, and the first examples of measures.Lebesgue MeasureUp next
  2. 02σ-algebras and Borel setsWhich sets receive a size: σ-algebras as collections of answerable questions, partitions and atoms, generated σ-algebras, Borel sets and Vitali's set.σ-Algebras
  3. 03Lebesgue measure and null setsBuilding length for every Borel set: countable covers and outer measure, sets of length zero, the Cantor sets, almost everywhere, and why length is unique.Lebesgue Measure
  4. 04Measurable functionsFunctions whose level sets can be measured: preimages, the half-line test, closure under limits, simple functions, σ(f) and the image measure.Random Variables
  5. 05The Lebesgue integralIntegrals built from simple functions by slicing the range: the layer-cake formula, integrable functions, sums as integrals, and Riemann versus Lebesgue.Lebesgue Integral
  6. 06Convergence theoremsWhen the limit of integrals is the integral of the limit: escaping mass, monotone convergence, Fatou's lemma, dominated convergence and series of integrals.Convergence
  7. 07Probability spaces and Kolmogorov's axiomsProbability as a measure of total mass one: outcomes, events and axioms, discrete and continuous models, infinite coin tossing, almost sure events.Probability Space
  8. 08Random variables and their distributionsRandom variables as measurable functions and the distributions they carry: distribution functions, atoms and densities, common laws, quantiles, sampling.Random Variables
  9. 09Expectation, variance and inequalitiesExpectation as an integral, computed from the distribution or from tails; linearity, variance and moments; the Markov, Chebyshev and Jensen inequalities.Lebesgue Integral
  10. 10Independence and product measuresIndependent events, σ-algebras and random variables, covariance and the variance of sums, product measures, Fubini's theorem and independent coin tosses.σ-Algebras
  11. 11Modes of convergence and the law of large numbersAlmost sure, in probability, in mean and in distribution: how they differ, the Borel–Cantelli lemma, uniform integrability and the laws of large numbers.Convergence
  12. 12Conditional probability and conditional expectationConditioning on an event, Bayes' rule, block averages over a partition, conditional expectation given a σ-algebra, best prediction and the tower property.Conditional Expectation
  13. 13Measure theory in option pricingHow the measure theory and probability of this track meet in option pricing: equivalent measures and densities, information, conditional expectation, limits.Probability Space · σ-Algebras · Conditional Expectation

About this tool

Narrative guides that connect the interactive tools into a story: financial instruments and their payoffs, the no-arbitrage principle, risk-neutral pricing, delta hedging and the road to the Black–Scholes formula. Each guide links to the labs where you can try the ideas yourself.

Frequently asked questions

In what order should I read the guides?

Start with instruments and no-arbitrage, then risk-neutral pricing and delta hedging; together they lead to the Black–Scholes formula.

Who are the guides for?

Students of financial and insurance mathematics and anyone who wants intuition behind derivatives pricing, not just the formulas.