Category: News

Sreoshi Banerjee (QSMS Research Group, BME)  will be presenting her paper “GENERALIZED WELFARE LOWER BOUNDS AND STRATEGYPROOFNESS IN
SEQUENCING PROBLEMS “ on October 25th at 10 AM, room QA405. One-to-one meetings with the speaker can be arranged; please contact the seminar organizers, Dr. Noémie Cabau (cabau.noemie@gtk.bme.hu) and Dr. Arseniy Samsonov (samsonov.arseniy@gtk.bme.hu).  

Abstract:  In an environment with private information, we study the class of sequencing problems with welfare lower bounds. The ‘generalized welfare lower bound’ is a universal representation of some of the specific lower bounds that have been previously studied in the literature. Every agent is offered protection in the form of a minimum guarantee on their utilities. We provide a necessary and sufficient condition to identify an outcome-efficient and strategyproof mechanism that satisfies the generalized welfare lower bound. We then characterize the entire class of mechanisms that satisfy outcome efficiency, strategyproofness, and generalized welfare lower bound. These are termed as ‘relative pivotal mechanisms’. Our paper proposes relevant theoretical applications namely; ex-ante initial order, identical costs bound and expected cost bound. We also give insights on the issues of feasibility and/or budget balance. 

Ryan Tierney from the University of Southern Denmark will be presenting his paper “Crowding in School Choice“ on October 18th at 10 AM, room QA405. One-to-one meetings with the speaker can be arranged; please contact the seminar organizers, Dr. Noémie Cabau (cabau.noemie@gtk.bme.hu) and Dr. Arseniy Samsonov (samsonov.arseniy@gtk.bme.hu).  

Abstract:  We consider the market design problem of matching students to schools in the presence of crowding effects. These effects are salient in parents’ decision making and the empirical literature; however, they cause major difficulties in the design of satisfactory mechanisms and, as such, are not currently considered. We propose a new framework and an equilibrium notion that accommodates crowding, no-envy, and respect for priorities. The equilibrium has a student-optimal element that induces an incentive compatible mechanism and is implementable via a novel algorithm. Moreover, analogs of fundamental structural results of the matching literature—the Rural Hospitals Theorem, welfare lattice, etc.—survive.

Vivien Surman from BME, Management department, will be presenting her paper “Characterizing clusters of students and supervisors based on an empirical study in the case of project work courses“ on October 11th at 10 AM, room QA405. One-to-one meetings with the speaker can be arranged; please contact the seminar organizers, Dr. Noémie Cabau (cabau.noemie@gtk.bme.hu) and Dr. Arseniy Samsonov (samsonov.arseniy@gtk.bme.hu).  

Abstract:  The purpose of this research is to describe the different clusters of students completing project work courses and to characterize lecturers acting as supervisors as well. The existence of different student groups setting different requirements against the supervising process has been emerged by supervisor focus group interviews in the improvement process of a service quality framework for project work courses. Cluster analyses based upon data from this service quality framework have proved the presence of three well-definable student groups. At the same time, the specific attributes of the supervisors including age, experience, grade distribution have also been gathered and analysed. The student classification is based on feedbacks of 1500 students. Supervisor characterization results from the analyses of 800 previously finished project work courses. As a result, it could be confirmed that both the students and the supervisors could be classified into well-defined groups in the case of project work courses. Finally, the characteristics of the identified groups of students and that of supervisors have been compared with statistical methods, highlighting connections between the groups. As these project work courses are remarkable cornerstones of total higher education student experience, characterizing the service quality features of the supervision process is vital. On the long run, the successful pairing of student groups with supervisor groups having specific features could be carried out for the sake of successful student accomplishment and for standardizing the supervision process as well. 

Dov Samet from the Coller School of Management at Tel Aviv University will be presenting his paper “Desirability” on October 4th at 10 AM, room QA405. One-to-one meetings with the speaker can be arranged; please contact the seminar organizers, Dr. Noémie Cabau (cabau.noemie@gtk.bme.hu) and Dr. Arseniy Samsonov (samsonov.arseniy@gtk.bme.hu).  

Abstract:  We propose a model of an agent’s probability and utility that is a compromise between Savage (1954) and Jeffrey (1965). In Savage’s model the probability-utility pair is associated with preferences over acts which are assignments of consequences to states. The probability is defined on the state space, and the utility function on consequences. Jeffrey’s model has no consequences, and both probability and utility are defined on the same set of propositions. The probability-utility pair is associated with a desirability relation on propositions. Like Savage we assume a set of consequences and a state space. However, we assume that states are comprehensive, that is, each state describes a consequence, as in Aumann (1987). Like Jeffrey, we assume that the agent has a preference relation, which we call desirability, over events, which by definition involves uncertainty about consequences. For a given probability and utility of consequences, the desirability relation is presented by conditional expected utility, given an event. We axiomatically characterize desirability relations that are represented by a probability-utility pair. We characterize the family of all the probability-utility pairs that represent a given desirability relation.

Anastas Tenev from the Institute of Economics at Corvinus University will present his paper “Information Design for Weighted Voting” (co-authored with Toygar T. Kerman) on September 20th at 10 AM, room QA405. One-to-one meetings with the speaker can be arranged; please contact the seminar organizers, Dr. Noémie Cabau (cabau.noemie@gtk.bme.hu) and Dr. Arseniy Samsonov (samsonov.arseniy@gtk.bme.hu).  

Abstract:  We consider a sender who wishes to persuade multiple receivers to vote in favor of a proposal and sends them correlated messages that are conditional on the true state of the world. The receivers share a common prior, wish to implement the outcome that matches the true state, and have homogeneous preferences, but are heterogeneous in their voting weights. Given a weight profile, an optimal signal can be represented by a tractable linear programming problem. We employ insights from cooperative game theory and interpret the voting problem as a simple game to analyze optimal communication for various voting situations. While public communication is optimal under weak, oligarchic, or dictatorial games, the sender can significantly benefit from private communication under symmetric, strong, or non-weak proper games. To the best of our knowledge, this is the first attempt to analyze a weighted voting application of Bayesian persuasion. 

The QSMS Research Group (BME) will be hosting two seminars this August 2022. One-to-one meetings with the speakers can be arranged; please contact the seminar organizers, Dr. Noémie Cabau (cabau.noemie@gtk.bme.hu) and Dr. Arseniy Samsonov (samsonov.arseniy@gtk.bme.hu).  

Dhandabani S from the Indian Institute of Technology Madras (Decision Engineering Lab, Department of Management Studies) will be presenting his paper Modeling interactions between vertically cooperative and horizontally competitive newsvendor on the 30^th of August 2022 at 4PM, Room QA406. 

Abstract:  Consider a market served by both the supplier and the retailer, a typical example of a dual-channel supply chain. Supplier holds a fixed number of perishable inventories and shares them with the retailer for better reach. Also, because of the price matching guarantee, both the parties agree on a uniform retail price for customers, and it is set by the supplier along with the wholesale price. We assume that both the parties are profit-maximising newsvendors, i.e., retailer and supplier are quantity-setting and price-setting newsvendors, respectively. However, given the nature of the setting, their decisions are dependent on each other. As a result, none of them can control the environment solely and both set out to maximise their own profits, which calls for a game-theoretic perspective on the coopetitive (vertically cooperative and horizontally competitive) two-newsvendor setting. We model the interactions between the supplier and retailer as a Stackelberg game, with the supplier being the leader and the retailer being the follower. Given the price[1]sensitive nature of the demand, the retailer estimates her optimal quantity as a function of retail and wholesale prices as a function of the reaction curve. Exploiting the backward induction, the supplier leverages the retailer’s optimal quantity to base its pricing decisions. As the optimal solution becomes intractable for a generic demand uncertainty, focusing only on additive demand uncertainty, we derive sufficient optimality conditions for the supplier’s profit function to be concave with respect to both the retail and wholesale prices. Furthermore, we compute the best feasible set of quantity and price points that satisfy the already established restrictions and assumptions. Finally, extensive sensitivity analysis of the model parameters yields the following several managerial insights, out of which a few novel and counterintuitive are as follows: (i) supplier’s expected profit decreases with the capacity, (ii) the more the variation, supplier’s gain increases whereas retailer’s gain decreases, (iii) with a highly sensitive market, both the parties’ profits decrease, and (iv) retailer’s profit is concave with respect to the market potential. 

The QSMS Research Group (BME) will be hosting two seminars this August 2022. One-to-one meetings with the speakers can be arranged; please contact the seminar organizers, Dr. Noémie Cabau (cabau.noemie@gtk.bme.hu) and Dr. Arseniy Samsonov (samsonov.arseniy@gtk.bme.hu).  

Mikhail Freer from the University of Essex (Department of Economics) will be presenting his paper Constitutional Design (co-authored with César Martinelli) on the 23^rd of August 2022 at 4PM, Room QA406.  

Abstract: Constitution is the cornerstone of any democracy: defining both the basic rights of citizens and the rules of the political process. However, most political economy literature frequently overlooks the constitution as a whole, focusing on bargaining between legislator and executive. This paper expands the scope and considers all three branches of power in the constitutional mechanism. First, we show that the constitutional mechanism (even with the accountability of the executive and legislator) cannot be credible without the presence of the “fourth power” (civic society). However, this fourth power is not directly governed by the constitution, and to restore the credibility of the constitution, the two key features are (1) society is affected by the outcomes of legislative bargaining, and (2) the judiciary is responsive to public opinion. However, these features are not enough to restore the “efficiency” of the constitution; to do so, we need to ensure that society does not stop pressuring the government with just the resignation of the corresponding official but gets a more direct involvement in the further legislative bargaining.