Assignments

The Problem Sets were due in the lecture sessions listed in the table. 25% of the course grade is based on the problem sets.


LEC # Assignments Topics
4 Problem Set 1 (PDF) Asymptotics of Rayleigh's random walk, Central Limit Theorem, Gram-Charlier expansion

Exact solution for the position of Cauchy's random walk with non-identical steps

Computer simulation of Pearson's random walk to find the fraction of time spent in the right half plane ("arcsine law") and the first quadrant
8 Problem Set 2 (PDF) Percentile order statistics, asymptotics of the median versus the mean

Computer simulation of the winding angle for Pearson's random walk, logarithmic scaling and limiting distribution 

Globally-valid saddle-point asymptotics for a random walk with exponentially distributed displacements 

The Void Model for granular drainage, continuum limits for the void density (mean flow profile) and the position a tracer particle, exact similarity solutions for parabolic flow to a point orifice
15 Problem Set 3 (PDF) Modified Kramers-Moyall expansion for a general discrete Markov process 

Black-Scholes formula for a call option, interpretation as risk neutral valuation, put-call parity 

Continuum limit of Bouchaud-Sornette theory for options with residual risk (corrections to the Black-Scholes equation)
24 Problem Set 4 (PDF) Linear polymer structure. Random walk with exponentially decaying correlations, depending on temperature 

Polymer surface adsorption. First passage to a plane, Levy flight for adsorption sites, scalings with the chain length 

Solution to the Telegrapher's equation. Fourier-Laplace transform, wave and diffusion limits, exact Green function 

Inelastic diffusion. Random walk with exponentially decaying steps, approach to the Central Limit Theorem