Have a personal or library account? Click to login
Discrete-time market models from the small investor point of view and the first fundamental-type theorem Cover

Discrete-time market models from the small investor point of view and the first fundamental-type theorem

By: Marek Karaś and  Anna Serwatka  
Open Access
|Jan 2018

Abstract

In this paper, we discuss the no-arbitrage condition in a discrete financial market model which does not hold the same interest rate assumptions. Our research was based on, essentially, one of the most important results in mathematical finance, called the Fundamental Theorem of Asset Pricing. For the standard approach a risk-free bank account process is used as numeraire. In those models it is assumed that the interest rates for borrowing and saving money are the same. In our paper we consider the model of a market (with d risky assets), which does not hold the same interest rate assumptions. We introduce two predictable processes for modelling deposits and loans. We propose a new concept of a martingale pair for the market and prove that if there exists a martingale pair for the considered market, then there is no arbitrage opportunity. We also consider special cases in which the existence of a martingale pair is necessary and the sufficient conditions for these markets to be arbitrage free.

DOI: https://doi.org/10.1515/aupcsm-2017-0002 | Journal eISSN: 2300-133X | Journal ISSN: 2081-545X
Language: English
Page range: 17 - 40
Submitted on: Mar 14, 2016
Accepted on: May 12, 2017
Published on: Jan 27, 2018
Published by: Pedagogical University of Cracow
In partnership with: Paradigm Publishing Services
Publication frequency: 1 issue per year

© 2018 Marek Karaś, Anna Serwatka, published by Pedagogical University of Cracow
This work is licensed under the Creative Commons Attribution-ShareAlike 4.0 License.