Abstract
In 1956 R. D. Luce introduced the notion of a semiorder to deal with indifference relations in the representation of a preference. During several years the problem of finding a utility function was studied until a representability characterization was found. However, there was almost no results on the continuity of the representation. A similar result to Debreu’s Lemma, but for semiorders was never achieved. In the present paper we propose a characterization for the existence of a continuous representation (in the sense of Scott-Suppes) for bounded semiorders. As a matter of fact, the weaker but more manageable concept of \(\varepsilon \)-continuity is properly introduced for semiorders. As a consequence of this study, a version of the Debreu’s Open Gap Lemma is presented (but now for the case of semiorders) just as a conjecture, which would allow to remove the open-closed and closed-open gaps of a subset \(S\subseteq \mathbb {R}\), but now keeping the constant threshold, so that \(x+1<y\) if and only if \(g(x)+1<g(y) \, (x,y\in S)\).
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Notes
- 1.
Observe that \(\tau \) does not coincide with the induced topology \( \tau _{u|_X}\) inherited from the usual topology \(\tau _u\) on \(\mathbb {R}\). As a matter of fact \(\tau \subsetneq \tau _{u|_X}\).
- 2.
J denotes here a directed set of indices. Since this does not lead to confusion, we will use the same notation ‘<’ of the order on the real numbers than for the partial order on the set of indices J.
- 3.
Here, notice that the sequence \(\{u_n\}_{n\in \mathbb {N}}\) is a Cauchy sequence with respect to the sup norm.
References
Aleskerov, F., Bouyssou, D., Monjardet, B.: Utility Maximization, Choice and Preference, 2nd edn. Springer, Berlin (2007)
Bosi, G.: Continuous representations of interval orders based on induced preorders. Rivista di Matematica per le Scienze Economiche e Soziali 18(1), 75–82 (1995)
Bosi, G., Campión, M.J., Candeal, J.C., Induráin, E.: Interval-valued representability of qualitative data: the continuous case. Internat. J. Uncertain. Fuzziness Knowl. Based Syst. 15(3), 299–319 (2007)
Bosi, G., Candeal, J.C., Induráin, E.: Continuous representability of interval orders and biorders. J. Math. Psych. 51, 122–125 (2007)
Bosi, G., Candeal, J.C., Induráin, E., Olóriz, E., Zudaire, M.: Numerical representations of interval orders. Order 18, 171–190 (2001)
Bosi, G., Estevan, A., Gutiérrez-García, J., Induráin, E.: Continuous representability of interval orders: the topological compatibility setting internat. J. Uncertain. Fuzziness Knowl. Based Syst. 23(03), 345–365 (2015)
Bosi, G., Zuanon, M.E.: Semicontinuous representability of interval orders on a metrizable topological space. Int. J. Contemp. Math. Sci. 2(18), 853–858 (2007)
Bosi, G., Zuanon, M.E.: Representations of an interval order by means of two upper semicontinuous functions. Int. Math. Forum 6(42), 2067–2071 (2011)
Bridges, D.S., Mehta, G.B.: Representations of Preference Orderings. Springer, Berlin-Heidelberg-New York (1995)
Campión, M.J., Candeal, J.C., Induráin, E.: On Yi’s extension property for totally preordered topological spaces. J. Korean Math. Soc. 43(1), 159–181 (2006)
Campión, M.J., Candeal, J.C., Induráin, E.: Semicontinuous planar total preorders on non-separable metric spaces. J. Korean Math. Soc. 46(4), 701–711 (2009)
Campión, M.J., Candeal, J.C., Induráin, E., Mehta, G.B.: Continuous order representability properties of topological spaces and algebraic structures. J. Korean Math. Soc. 49(3), 449–473 (2012)
Campión, M.J., Candeal, J.C., Induráin, E., Zudaire, M.: Continuous representability of semiorders. J. Math. Psych. 52, 48–54 (2008)
Candeal, J.C., Estevan, A., Gutiérrez-García, J., Induráin, E.: Semiorders with separability properties. J. Math. Psychol. 56, 444–451 (2012)
Candeal, J.C., Induráin, E.: Semiorders and thresholds of utility discrimination: solving the Scott-Suppes representability problem. J. Math. Psych. 54, 485–490 (2010)
Candeal, J.C., Induráin, E., Sanchis, M.: Order representability in groups and vector spaces. Expo. Math. 30, 103–123 (2012)
Candeal, J.C., Induráin, E., Zudaire, M.: Numerical representability of semiorders. Math. Soc. Sci. 43(1), 61–77 (2002)
Candeal, J.C., Induráin, E., Zudaire, M.: Continuous representability of interval orders. Appl. Gen. Topol. 5(2), 213–230 (2004)
Chateauneuf, A.: Continuous representation of a preference relation on a connected topological space. J. Math. Econom. 16, 139–146 (1987)
Debreu, G.: Continuity properties of paretian utility. Internat. Econom. Rev. 5, 285–293 (1964)
Estevan, A.: Generalized Debreu’s open gap lemma and continuous representability of biorders. Order 33(2), 213–229 (2016)
Estevan, A., Gutiérrez García, J., Induráin, E.: Further results on the continuous representability of semiorders. Internat. J. Uncertain. Fuzziness Knowl. Based Syst. 21(5), 675–694 (2013)
Fishburn, P.C.: Intransitive indifference with unequal indifference intervals. J. Math. Psych. 7, 144–149 (1970)
Fishburn, P.C.: Intransitive indifference in preference theory: a survey. Oper. Res. 18(2), 207–228 (1970)
Fishburn, P.C.: Utility Theory for Decision-Making. Wiley, New York (1970)
Fishburn, P.C.: Interval representations for interval orders and semiorders. J. Math. Psych. 10, 91–105 (1973)
Fishburn, P.C.: Interval Orders and Interval Graphs. Wiley, New York (1985)
Fishburn, P.C., Monjardet, B.: Norbert Wiener on the theory of measurement (1914, 1915, 1921). J. Math. Psychol. 36, 165–184 (1992)
Gensemer, S.H.: Continuous semiorder representations. J. Math. Econom. 16, 275–289 (1987)
Luce, R.D.: Semiorders and a theory of utility discrimination. Econometrica 24, 178–191 (1956)
Monjardet, B.: Axiomatiques et propriétés des quasi-ordres. Math. Sci. Hum. 63, 51–82 (1978)
Olóriz, E., Candeal, J.C., Induráin, E.: Representability of interval orders. J. Econom. Theory 78(1), 219–227 (1998)
Scott, D., Suppes, P.: Foundational aspects of theories of measurement. J. Symbolic Logic 23, 113–128 (1958). 54, 485–490 (2010)
Vincke, P.: Linear utility functions on semiordered misture spaces. Econometrica 48(3), 771–775 (1980)
Wiener, N.: Contribution to the theory of relative position. Math. Proc. Cambridge Philos. Soc. 17, 441–449 (1914)
Wiener, N.: A new theory of measurement. Proc. London Math. Soc. 19, 181–205 (1919)
Acknowledgements
The author acknowledges financial support from the Ministry of Economy and Competitiveness of Spain under grants MTM2015-63608-P and ECO2015-65031.
I am grateful for the helpful advice of the anonymous referees, to whom I am indebted for the detailed reading of previous versions of the manuscript and their very helpful suggestions and comments.
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Estevan, A. (2020). Searching for a Debreu’s Open Gap Lemma for Semiorders. In: Bosi, G., Campión, M., Candeal, J., Indurain, E. (eds) Mathematical Topics on Representations of Ordered Structures and Utility Theory. Studies in Systems, Decision and Control, vol 263. Springer, Cham. https://doi.org/10.1007/978-3-030-34226-5_5
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