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Properly discounted asset prices are semimartingales

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Abstract

We study general undiscounted asset price processes, which are only assumed to be nonnegative, adapted and RCLL (but not a priori semimartingales). Traders are allowed to use simple (piecewise constant) strategies. We prove that under a discounting-invariant condition of absence of arbitrage, the original prices discounted by the value process of any simple strategy with positive wealth must follow semimartingales. We also establish a corresponding version of the fundamental theorem of asset pricing that involves supermartingale discounters with an additional strict positivity property.

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References

  1. Bálint, D.Á., Schweizer, M.: Making no-arbitrage discounting-invariant: a new FTAP beyond NFLVR and NUPBR. Swiss Finance Institute Research Paper No. 18–23, (2019). http://papers.ssrn.com/sol3/papers.cfm?abstract_id=3141770

  2. Beiglböck, M., Schachermayer, W., Veliyev, B.: A direct proof of the Bichteler–Dellacherie theorem and connections to arbitrage. Ann. Probab. 39, 2424–2440 (2011)

    Article  MathSciNet  Google Scholar 

  3. Beiglböck, M., Siorpaes, P.: Riemann-integration and a new proof of the Bichteler–Dellacherie theorem. Stochast. Process. Appl. 124, 1226–1235 (2014)

    Article  MathSciNet  Google Scholar 

  4. Bichteler, K.: Stochastic integrators. Bull. Am. Math. Soc. New Ser. 1, 761–765 (1979)

    Article  MathSciNet  Google Scholar 

  5. Cheridito, P.: Arbitrage in fractional Brownian motion models. Finance Stochast. 7, 533–553 (2003)

    Article  MathSciNet  Google Scholar 

  6. Czichowsky, C., Schachermayer, W.: Portfolio optimisation beyond semimartingales: shadow prices and fractional Brownian motion. Ann. Appl. Probab. 27, 1414–1451 (2017)

    Article  MathSciNet  Google Scholar 

  7. Delbaen, F., Schachermayer, W.: A general version of the fundamental theorem of asset pricing. Math. Ann. 300, 463–520 (1994)

    Article  MathSciNet  Google Scholar 

  8. Dellacherie, C., Meyer, P.-A.: Probabilities and Potential B. Theory of Martingales, North-Holland (1982)

    MATH  Google Scholar 

  9. Guasoni, P.: Optimal investment with transaction costs and without semimartingales. Ann. Appl. Probab. 12, 1227–1246 (2002)

    Article  MathSciNet  Google Scholar 

  10. Jacod, J.: Calcul Stochastique et Problèmes de Martingales. Lecture Notes in Mathematics, vol. 714. Springer, Berlin (1979)

    Book  Google Scholar 

  11. Kardaras, C.: Finitely additive probabilities and the fundamental theorem of asset pricing. In: Chiarella, C., Novikov, A. (eds.) Contemporary Quantitative Finance, Essays in Honour of Eckhard Platen, pp. 19–34. Springer, Berlin (2010)

    Chapter  Google Scholar 

  12. Kardaras, C., Platen, E.: On the semimartingale property of discounted asset-price processes. Stochast. Process. Appl. 121, 2678–2691 (2011)

    Article  MathSciNet  Google Scholar 

  13. Kardaras, C.: On the closure in the Emery topology of semimartingale wealth-process sets. Ann. Appl. Probab. 23, 1355–1376 (2013)

    Article  MathSciNet  Google Scholar 

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Acknowledgements

We gratefully acknowledge financial support by the ETH Foundation via the Stochastic Finance Group (SFG) at ETH Zurich and by the Swiss Finance Institute (SFI). The first author thanks Matteo Burzoni for discussions, questions and general support. We also thank two anonymous referees and an Associate Editor for critical comments that led us to rewrite our paper and explain our contribution more clearly.

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Correspondence to Martin Schweizer.

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Bálint, D.Á., Schweizer, M. Properly discounted asset prices are semimartingales. Math Finan Econ 14, 661–674 (2020). https://doi.org/10.1007/s11579-020-00269-8

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  • DOI: https://doi.org/10.1007/s11579-020-00269-8

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