{
  "id": "1202.2999",
  "version": "v1",
  "published": "2012-02-14T11:14:51.000Z",
  "updated": "2012-02-14T11:14:51.000Z",
  "title": "Optimal arbitrage under model uncertainty",
  "authors": [
    "Daniel Fernholz",
    "Ioannis Karatzas"
  ],
  "comment": "Published in at http://dx.doi.org/10.1214/10-AAP755 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org)",
  "journal": "Annals of Applied Probability 2011, Vol. 21, No. 6, 2191-2225",
  "doi": "10.1214/10-AAP755",
  "categories": [
    "math.PR",
    "q-fin.PM"
  ],
  "abstract": "In an equity market model with \"Knightian\" uncertainty regarding the relative risk and covariance structure of its assets, we characterize in several ways the highest return relative to the market that can be achieved using nonanticipative investment rules over a given time horizon, and under any admissible configuration of model parameters that might materialize. One characterization is in terms of the smallest positive supersolution to a fully nonlinear parabolic partial differential equation of the Hamilton--Jacobi--Bellman type. Under appropriate conditions, this smallest supersolution is the value function of an associated stochastic control problem, namely, the maximal probability with which an auxiliary multidimensional diffusion process, controlled in a manner which affects both its drift and covariance structures, stays in the interior of the positive orthant through the end of the time-horizon. This value function is also characterized in terms of a stochastic game, and can be used to generate an investment rule that realizes such best possible outperformance of the market.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2012-02-14T11:14:51.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "model uncertainty",
      "optimal arbitrage",
      "nonlinear parabolic partial differential equation",
      "investment rule",
      "auxiliary multidimensional diffusion process"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2012arXiv1202.2999F"
    }
  }
}