Efficient Counterfactual Estimation of Conditional Greeks via Malliavin-based Weak Derivatives

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Krishnamurthy, Vikram, Snow, Luke
Format: Preprint
Publié: 2026
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866914303489081344
author Krishnamurthy, Vikram
Snow, Luke
author_facet Krishnamurthy, Vikram
Snow, Luke
contents We study counterfactual gradient estimation of conditional loss functionals of diffusion processes. In quantitative finance, these gradients are known as conditional Greeks: the sensitivity of expected market values, conditioned on some event of interest. The difficulty is that when the conditioning event has vanishing or zero probability, naive Monte Carlo estimators are prohibitively inefficient; kernel smoothing, though common, suffers from slow convergence. We propose a two-stage kernel-free methodology. First, we show using Malliavin calculus that the conditional loss functional of a diffusion process admits an exact representation as a Skorohod integral, yielding classical Monte-Carlo estimator variance and convergence rates. Second, we establish that a weak derivative estimate of the conditional loss functional with respect to model parameters can be evaluated algorithmically with constant variance, in contrast to the widely used score function method whose variance grows linearly in the sample path length. Together, these results yield an efficient framework for counterfactual conditional stochastic gradient algorithms and financial Greek computations in rare-event regimes.
format Preprint
id arxiv_https___arxiv_org_abs_2602_02811
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Efficient Counterfactual Estimation of Conditional Greeks via Malliavin-based Weak Derivatives
Krishnamurthy, Vikram
Snow, Luke
Computational Engineering, Finance, and Science
We study counterfactual gradient estimation of conditional loss functionals of diffusion processes. In quantitative finance, these gradients are known as conditional Greeks: the sensitivity of expected market values, conditioned on some event of interest. The difficulty is that when the conditioning event has vanishing or zero probability, naive Monte Carlo estimators are prohibitively inefficient; kernel smoothing, though common, suffers from slow convergence. We propose a two-stage kernel-free methodology. First, we show using Malliavin calculus that the conditional loss functional of a diffusion process admits an exact representation as a Skorohod integral, yielding classical Monte-Carlo estimator variance and convergence rates. Second, we establish that a weak derivative estimate of the conditional loss functional with respect to model parameters can be evaluated algorithmically with constant variance, in contrast to the widely used score function method whose variance grows linearly in the sample path length. Together, these results yield an efficient framework for counterfactual conditional stochastic gradient algorithms and financial Greek computations in rare-event regimes.
title Efficient Counterfactual Estimation of Conditional Greeks via Malliavin-based Weak Derivatives
topic Computational Engineering, Finance, and Science
url https://arxiv.org/abs/2602.02811