BUSCADOR RECOLECTA

In the present paper, we propose a new approach on ‘distributed systems’: the processes
are represented through total orders and the communications are characterized by
means of biorders. The resulting distributed systems capture situations met in various
fields (such as computer science, economics and decision theory). We investigate
questions associated to the numerical representability of order structures, relating
concepts of economics and computing to each other. The concept of ‘quasi-finite
partial orders’ is introduced as a finite family of chains with a communication between
them. The representability of this kind of structure is studied, achieving a construction
method for a finite (continuous) Richter–Peleg multi-utility representation., This work has been partially supported by the research project PID2021-127799NBI00 from the Spanish Ministry of Science Innovation and Universities. The author also acknowledges
financial support from the Public University of Navarre (UPNA), under grant JIUPNA19-2022. Open Access funding provided by Universidad Pública de Navarra.

We present an experiment to test different individual attitudes toward choice, such as preference for flexibility, choice aversion, betweenness and choice neutrality. Unlike other related experimental papers, we want to analyze whether different choice attitudes can coexist for the same subject, depending on the characteristics of the choice set she is facing. In particular, our main hypothesis is that the presence of incomparability among the alternatives in the choice set, and the time at which such incomparability is solved, affect crucially the kind of attitude towards choice that the subject will exhibit. We find that, indeed, choice attitudes are not homogeneous across choice sets, yet they are conditional on the preferences over the alternatives. We also find some evidence supporting that subjects tend to value heuristically sets as a whole., Financial support from the National Agency for Research (ANR-17-EURE-0017 FrontCog), from the Universidad Pública de Navarra (PID2020-
119703RB_I00 and PJUPNA19-2022), from the Spanish Ministry of Science and Innovation (PID2021-127799NB-I00) and from the Government of Navarre is acknowledged. Open access funding provided by Universidad Pública de Navarra

In this paper, the idea of myopic preference and myopic topology provided by Brown and Lewis is further explored. In this sense, new definitions of myopia are introduced for finite spaces. The main contribution of the work is the inclusion of the past in the models. We have defined the notions of past-myopic preference and topology for sequence spaces and n-dimensional spaces. Adding this new dimension makes it possible to work with decision spaces where the economic agent only has information about past events and when she has to choose accordingly to it, which is in line with the reality of certain economic situations, such as voting or finances. This approach generates a wide room for future research lines related to the idea of myopia. Based on this, it would allow to study in forthcoming research past-hyperopic topologies and preferences, and to interconnect different preferences, defined on the past and future models., This work was supported by the project of reference PID2022-136627NB-I00 from MCIN/AEI/10.13039/501100011033/FEDER, UE, by grant PID2021-127799NB-I00 from MCIN/AEI/10.13039/501100011033 and by ERDF A way ofmaking Europe.

En esta tesis se estudian las preferencias de un agente económico cuando éste tiene en cuenta distintos horizontes temporales, abordando tanto aquellas preferencias que tienen un comportamiento cortoplacista como las que apuestan por una visión a largo plazo.
En la primera parte, el concepto de preferencia miope introducido por Brown y Lewis [39] es definido en diversos espacios matemáticos, incluyendo aquellos casos donde el tiempo es considerado tanto una variable discreta como una continua.
Además, se proponen nuevas definiciones que ayudan a la modelización económica, como la miopía del pasado, el efecto ventana estrecha o las preferencias hipermétropes del pasado. El marco teórico es a su vez complementado con aplicaciones económicas y del campo de la elección social, como decisiones de política pública o los modelos de votación individual.
En la segunda parte de la tesis se profundiza en los modelos de bienestar intergeneracional, en los que el agente económico incluye su apuesta por la equidad y la sostenibilidad. En ella, los principales criterios de bienestar presentados en la literatura son redefinidos en el espacio de funciones L1[0, T]. El mismo proceso es llevado a cabo con los axiomas de sostenibilidad propuestos por Chichilnisky [56] y, en conjunto con nuevas definiciones de justicia social introducidas en este espacio de funciones, se construye una preferencia que es a su vez sostenible y justa.
Posteriormente, se apuesta por ampliar el enfoque clásico para incorporar otras situaciones particulares como la existencia de preferencias incompletas, las situaciones en las que hay una falta de discriminación entre las alternativas o los contextos de incertidumbre. Por este motivo, se introducen en el análisis nuevas ordenaciones como los semiórdenes y los preórdenes no completos y también las preferencias difusas (fuzzy preferences). En concreto, los resultados teóricos se centran en la representación de multiutilidad mediante un número numerable de funciones y en el estudio de los Hesitant Fuzzy Sets y sus scores. En ambos casos se proponen aplicaciones relacionadas con los modelos de capítulos anteriores.
En resumen, el eje central de la tesis es la representación de estructuras ordenadas y su aplicación a modelos económicos. La tesis es eminentemente teórica, pero en ella también se incluyen propuestas de aplicación que pueden contribuir a la apertura de nuevas líneas de investigación en Economía y en la Elección Social., This thesis studies the preferences of an economic agent who considers different time horizons, addressing both preferences that exhibit short-term behavior and those that promote a long-term perspective.
In the first part, the concept of myopic preference introduced by Brown and Lewis [39] is defined across various mathematical spaces, including cases where time is considered as either a discrete or continuous variable. Additionally, new definitions are proposed to enhance economic modeling, such as past myopia, the narrow window effect, and hyperopic preferences. The theoretical framework is further complemented by economic and social choice applications, such as public policy decisions and individual voting models.
The second part of the thesis delves into intergenerational welfare models, where the economic agent incorporates considerations of equity and sustainability.
In this context, the main welfare criteria presented in the literature are redefined in the function space L1[0, T]. A similar process is carried out with the sustainability axioms proposed by Chichilnisky [56], and together with new definitions of fairness introduced in this function space, a preference that is both sustainable and fair is constructed.
Subsequently, the classical approach is broadened to include particular situations such as incomplete preferences, lack of discrimination between alternatives, or contexts of uncertainty. For this reason, new order structures are introduced into the analysis, including semiorders, non-complete preorders, and fuzzy preferences. The theoretical results focus specifically on the representation of multiutility through a countable number of functions and on the study of Hesitant Fuzzy Sets and their associated scores. In both cases, applications are proposed that connect with the models introduced in earlier chapters.
In summary, the central axis of the thesis is the representation of ordered structures and their application to economic models. Although the thesis is primarily theoretical, it also includes applied proposals that may contribute to the development of new lines of research in Economics and Social Choice Theory., Financial support received through the Santander-UPNA 21/22 grant, the mobility grants from EDONA and Erasmus+, the project PID2021-127799NB-I00 funded by MCIN/AEI/10.13039/501100011033 and by ERDF “A way of making Europe”, as well as under grant JIUPNA19-2022 from the Public University of Navarre (UPNA), UPNA), and the internal funds from the Order Mathematics research group., Programa de Doctorado en Economía, Empresa y Derecho (RD 99/2011), Ekonomiako, Enpresako eta Zuzenbideko Doktoretza Programa (ED 99/2011)

In this article, we go deeper into the study of some types of decompositions defined by triangular norms and conorms. We work in the spirit of the classical Arrovian models in the fuzzy setting and their possible extensions. This allows us to achieve characterizations of existence and uniqueness for such decompositions. We provide rules to obtain them under some specific conditions. We conclude by applying the results achieved to the study of fuzzy preferences., This work has been partially supported by the research projects whose references are PID2019-108392GB-I00 (AEI/10.13039/501100011033), PID2021-127799NB-I00 and PID2022-1366274NBI00 from the Ministry of Science and Innovation of Spain, as well as the Ayudas para la Recualificación del Sistema Universitario Español para 2021-2023, UPNA. Modalidad Margarita Salas funded by the European Union-NextGenerationEU and a predoctoral grant from the UPNA Research Institutes.

The problem of finding a utility function for a semiorder has been studied since 1956, when the notion of semiorder was introduced by Luce. But few results on continuity and no result like Debreu’s Open Gap Lemma, but for semiorders, was found. In the present paper, we characterize semiorders that accept a continuous representation (in the sense of Scott–Suppes). Two weaker theorems are also proved, which provide a programmable approach to Open Gap Lemma, yield a Debreu’s Lemma for semiorders, and enable us to remove the open-closed and closed-open gaps of a set of reals while keeping the threshold., Asier Estevan acknowledges financial support from the Ministry of Science and Innovation of Spain under grants PID2020-119703RB-I00 and PID2021-127799NB-I00 as well as from the UPNA, Spain under grant JIUPNA19-2022.

In this paper, we provide the counterparts of a few celebrated impossibility theorems for continuous social intergenerational preferences according to P. Diamond, L.G. Svensson and T. Sakai. In particular, we give a topology that must be refined for continuous preferences to satisfy anonymity and strong monotonicity. Furthermore, we suggest quasi-pseudo-metrics as an appropriate quantitative tool for reconciling topology and social intergenerational preferences. Thus, we develop a metric-type method which is able to guarantee the possibility counterparts of the aforesaid impossibility theorems and, in addition, it is able to give numerical quantifications of the improvement of welfare. Finally, a refinement of the previous method is presented in such a way that metrics are involved., Asier Estevan acknowledges financial support from the Ministry of Science and Innovation of Spain under grant PID2021-127799NB-I00 as well as from the UPNA under grant JIUPNA19-2022. Oscar Valero acknowledges financial support from Proyecto PGC2018-095709-B-C21 financiado por MCIN/AEI/10.13039/501100011033 y FEDER “Una manera de hacer Europa” and from project BUGWRIGHT2. This last project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 871260.