Infinite Portfolio Strategies

In continuous-time stochastic calculus a limit in probability is used to extend the definition of the stochastic integral to the case where the integrand is not square-integrable at the endpoint of the time interval under consideration. When the extension is applied to portfolio strategies, absence...

Full description

Saved in:
Bibliographic Details
Main Author: Stephen F. LeRoy
Format: Article
Language:English
Published: VIZJA University 2012-12-01
Series:Contemporary Economics
Online Access:http://ce.vizja.pl/en/download-pdf/id/270
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850230096642703360
author Stephen F. LeRoy
author_facet Stephen F. LeRoy
author_sort Stephen F. LeRoy
collection DOAJ
description In continuous-time stochastic calculus a limit in probability is used to extend the definition of the stochastic integral to the case where the integrand is not square-integrable at the endpoint of the time interval under consideration. When the extension is applied to portfolio strategies, absence of arbitrage in finite portfolio strategies is consistent with existence of arbitrage in infinite portfolio strategies. The doubling strategy is the most common example. We argue that this extension may or may not make economic sense, depending on whether or not one thinks that valuation should be continuous. We propose an alternative extension of the definition of the stochastic integral under which valuation is continuous and absence of arbitrage is preserved. The extension involves appending a date and state called to the payoff index set and altering the definition of convergence under which gains on infinite portfolio strategies are defined as limits of gains on finite portfolio strategies.
format Article
id doaj-art-e912ab2c70f94ed697e79e23bb0d64f4
institution OA Journals
issn 2084-0845
language English
publishDate 2012-12-01
publisher VIZJA University
record_format Article
series Contemporary Economics
spelling doaj-art-e912ab2c70f94ed697e79e23bb0d64f42025-08-20T02:03:58ZengVIZJA UniversityContemporary Economics2084-08452012-12-016416010.5709/ce.1897-9254.68Infinite Portfolio StrategiesStephen F. LeRoyIn continuous-time stochastic calculus a limit in probability is used to extend the definition of the stochastic integral to the case where the integrand is not square-integrable at the endpoint of the time interval under consideration. When the extension is applied to portfolio strategies, absence of arbitrage in finite portfolio strategies is consistent with existence of arbitrage in infinite portfolio strategies. The doubling strategy is the most common example. We argue that this extension may or may not make economic sense, depending on whether or not one thinks that valuation should be continuous. We propose an alternative extension of the definition of the stochastic integral under which valuation is continuous and absence of arbitrage is preserved. The extension involves appending a date and state called to the payoff index set and altering the definition of convergence under which gains on infinite portfolio strategies are defined as limits of gains on finite portfolio strategies.http://ce.vizja.pl/en/download-pdf/id/270
spellingShingle Stephen F. LeRoy
Infinite Portfolio Strategies
Contemporary Economics
title Infinite Portfolio Strategies
title_full Infinite Portfolio Strategies
title_fullStr Infinite Portfolio Strategies
title_full_unstemmed Infinite Portfolio Strategies
title_short Infinite Portfolio Strategies
title_sort infinite portfolio strategies
url http://ce.vizja.pl/en/download-pdf/id/270
work_keys_str_mv AT stephenfleroy infiniteportfoliostrategies