Games of capacity allocation in many-to-one matching with an aftermarket

In this paper, we study many-to-one matching (hospital–intern markets) with an aftermarket. We first show that every stable matching system is manipulable via aftermarket. We then analyze the Nash equilibria of capacity allocation games, in which preferences of hospitals and interns are common knowledge and every hospital determines a quota for the regular market given its total capacity for the two matching periods. Under the intern-optimal stable matching system, we show that a pure-strategy Nash equilibrium may not exist. Common preferences for hospitals ensure the existence of equilibrium in weakly dominant strategies whereas unlike in games of capacity manipulation strong monotonicity of population is not a sufficient restriction on preferences to avoid the non-existence problem. Besides, in games of capacity allocation, it is not true either that every hospital weakly prefers a mixed-strategy Nash equilibrium to any larger regular market quota profiles.     

Games of Capacity Manipulation in Hospital-intern Markets

In this paper, we analyze capacity manipulation games in hospital-intern markets inspired by the real-life entry-level labor markets for young physicians who seek residencies at hospitals. In a hospital-intern market, the matching is determined by a centralized clearinghouse using the preferences revealed by interns and hospitals and the number of vacant positions revealed by hospitals. We consider a model in which preferences of hospitals and interns are common knowledge. Hospitals play a capacity-reporting game. We analyze the equilibria of the game-form under the two most widely used matching rules: hospital-optimal and intern-optimal stable rules. We show that (i) there may not be a pure strategy equilibrium in general; and (ii) when a pure strategy equilibrium exists, every hospital weakly prefers this equilibrium outcome to the outcome of any larger capacity profile. Finally, we present conditions on preferences to guarantee the existence of pure strategy equilibria.     

Stable sets and standards of behaviour

In this paper we present a constructive, behavioural and axiomatic approach to the notion of a stable set as a model of the standard of behaviour of a social organisation. The socially stable set we introduce is a generalisation of the von Neumann-Morgenstern stable set. In contrast with the original version, our stability concept is always solvable. The standard of behaviour, reflecting the established conceptual order of a society or organisation, emerges from a dominance relation on alternative conceptions that are relevant with regard to a certain issue. This common social choice phenomenon, that permeates our societies and organisations, we have tried to clarify. Two axiomatic characterisations as well as a construction algorithm for socially stable sets are presented. These characterisations are based on behavioural postulates regarding the individual or collective strategic behaviour of effective sets. Relations between socially stable sets and other notions of stability are discussed. Received: 4 May 1998/13 March 2000     

Mixed Strategies in Games of Capacity Manipulation in Hospital–Intern Markets

We investigate games of capacity manipulation in hospital-intern markets as proposed by Konishi and ünver (Soc Choice Welfare, in press). While Konishi and ünver (Soc Choice Welfare, in press) show that there may not exist a pure-strategy Nash equilibrium in general, there exists a mixed-strategy Nash equilibrium in such a game. We show that every hospital weakly prefers a Nash equilibrium to any “larger” capacity profiles, whether the equilibrium is in pure or mixed strategies. In particular, a Nash equilibrium is weakly preferred by hospitals to the outcome that results from truthful reporting.     

An impossibility theorem for matching problems

This paper studies the possibility of strategy-proof rules yielding satisfactory solutions to matching problems. Alcalde and Barberá (Econ Theory 4:417–435, 1994) and Sönmez (Econ Des 1:365–380, 1994) show that efficient and individually rational matching rules are manipulable. We pursue the possibility of strategy-proof matching rules by relaxing efficiency to the weaker condition of respect for unanimity. First, we prove that a strategy-proof rule exists that is individually rational and respects unanimity. However, this rule is unreasonable in the sense that mutually best pairs of agents are matched on only rare occasions. In order to explore the possibility of better matching rules, we introduce a natural condition of “respect for 2-unanimity.” Respect for 2-unanimity states that a mutually best pair of agents should be matched, and an agent wishing to being unmatched should be unmatched. Our second result is negative. Secondly, we prove that no strategy-proof rule exists that respects 2-unanimity. This result implies Roth (Math Oper Res 7:617–628, 1962; J Econ Theory 36:277–288, 1985) showing that stable rules are manipulable.     

Ordinal Bayesian incentive compatible representations of committees

We consider the problem of strategic manipulation for decision schemes that provide an adequate representation (in some sense) of the distribution of power within a committee. Strategy-proof representation is very restrictive: it implies that the committee contains exactly one minimal winning coalition. So we introduce the weaker concept of Ordinally Bayesian Incentive Compatible representation and prove the existence of such representations for weak games under some conditions. Finally, constructing examples, we show first how necessary these conditions are—including the use of chance in the voting procedure — and second that we cannot avoid Condorcet's paradox.     

Smith and Rawls share a room: stability and medians

We consider one-to-one, one-sided matching (roommate) problems in which agents can either be matched as pairs or remain single. We introduce a so-called bi-choice graph for each pair of stable matchings and characterize its structure. Exploiting this structure we obtain as a corollary the “lone wolf” theorem and a decomposability result. The latter result together with transitivity of blocking leads to an elementary proof of the so-called stable median matching theorem, showing how the often incompatible concepts of stability (represented by the political economist Adam Smith) and fairness (represented by the political philosopher John Rawls) can be reconciled for roommate problems. Finally, we extend our results to two-sided matching problems.     

Hedonic games related to many-to-one matching problems

We consider the existence problem of stable matchings in many-to-one matching problems. Unlike other approaches which use algorithmic techniques to give necessary and sufficient conditions, we adopt a game theoretic point of view. We first associate, with each many-to-one matching problem, a hedonic game to take advantage of recent results guaranteeing the existence of core-partitions for that class of games, to build up our conditions. The main result states that a many-to-one matching problem, with no restrictions on individual preferences, has stable* matchings if and only if a related hedonic game is pivotally balanced. In the case that the preferences in the matching problem are substitutable, the notions of stability and stability* coincide.     

Simple Priorities and Core Stability in Hedonic Games

In this paper we study hedonic games where each player views every other player either as a friend or as an enemy. Two simple priority criteria for comparison of coalitions are suggested, and the corresponding preference restrictions based on appreciation of friends and aversion to enemies are considered. We characterize internally stable coalitions on the proposed domains and show how these characterizations can be used for generating a strict core element in the first case and a core element in the second case. Moreover, we prove that an element of the strict core under friends appreciation can be found in polynomial time, while finding an element of the core under enemies aversion is NP-hard.     

Instabile Beschäftigung

Sociologists and economists emphasize the relevance of employment stability for labour market participants and the welfare state. Consequently, changes in the distribution of stable and unstable employment are discussed intensively and controversially. Based on the IAB Employment Subsample 1975–2001 (regional sample) and the second collection of the SFB 580-Firmpanel the paper analyses trends and determinants of employment stability. The results show: Employment becomes more unstable. Past “barriers of mobility” of the job market theory against an expansion of open job markets, like production and receipt of firm specific knowledge or readiness to perform, prove as a little stable.     

Efficiency and stability in a model of wireless communication networks

We introduce a model of (wireless communication) networks: a group of agents want to communicate with each other; an agent has his own position, chooses his costly communication range, and benefits from direct and indirect communications with other agents; any two agents can directly communicate if each agent is located within another agent’s communication range; they can indirectly communicate if each agent is connected to another agent through a sequence of direct communications. Although efficiency and stability are not compatible in a general context, we identify interesting subclasses of problems where an efficient and stable network exists: the uniform interval model, the uniform circle model, and the communication favorable domain. We also investigate the consequence of allowing agents to relocate their positions. For certain networks, relocation-proofness is equivalent to stability.     

Driving complementarity in interdisciplinary research: a reflection

ABSTRACT

The value of interdisciplinary research is increasingly recognised by the research community. Funding bodies are nowadays specifically encouraging that research they fund is interdisciplinary in nature. However, what is often branded as interdisciplinary research is in fact a network of researchers working to deliver a research output. In this research note, we share our experience of what we think can be labelled “truly interdisciplinary”. We share some best practice tips for those who are interested to go through a similar metamorphosis as we did as a team, learning from each other’s ways of working. Overall, it has been a very positive experience and a revelation that has had a big impact on each author’s view on how to conduct research as an integrated multidisciplinary team, as it has shifted our mental models and broadened our thinking, capacity to reflect, and critical analysis. We hope that our research note clearly shows the benefits of truly interdisciplinary research and motivates other researchers to follow our pathway of transformation.     

The Lichtenberg Financial Decision Screening Scale (LFDSS): A new tool for assessing financial decision making and preventing financial exploitation

ABSTRACT

One of the challenges in preventing the financial exploitation of older adults is that neither criminal justice nor noncriminal justice professionals are equipped to detect capacity deficits. Because decision-making capacity is a cornerstone assessment in cases of financial exploitation, effective instruments for measuring this capacity are essential. We introduce a new screening scale for financial decision making that can be administered to older adults. To explore the scale’s implementation and assess construct validity, we conducted a pilot study of 29 older adults seen by APS (Adult Protective Services) workers and 79 seen by other professionals. Case examples are included.     

On ranking opportunity distributions

Our results show the intimate relationship between a large group of apparently different rankings of opportunity distributions. First, we provide a set of core basic axioms that are intuitively plausible under any concern for equality or efficiency aspects. Second, we introduce two very opposed views of the problem by incorporating different perspectives of the notion of advantage (better opportunity set) and we provide some axioms that might be defended under such extreme positions. For any of these two different perspectives, we characterize the families of rankings which satisfy the core axioms and the group of axioms corresponding to that view. These characterizations will prove insightful to better understand most of the criteria already introduced in the literature, which are part of the families we study.     

Closeness centrality via the Condorcet principle

We provide a characterization of closeness centrality in the class of distance-based centralities. To this end, we introduce a natural property, called majority comparison, that states that out of two adjacent nodes the one closer to more nodes is more central. We prove that any distance-based centrality that satisfies this property gives the same ranking in every graph as closeness centrality. The axiom is inspired by the interpretation of the graph as an election in which nodes are both voters and candidates and their preferences are determined by the distances to the other nodes.     

Social and semantic coevolution in knowledge networks

Socio-semantic networks involve agents creating and processing information: communities of scientists, software developers, wiki contributors and webloggers are, among others, examples of such knowledge networks. We aim at demonstrating that the dynamics of these communities can be adequately described as the coevolution of a social and a socio-semantic network. More precisely, we will first introduce a theoretical framework based on a social network and a socio-semantic network, i.e. an epistemic network featuring agents, concepts and links between agents and between agents and concepts. Adopting a relevant empirical protocol, we will then describe the joint dynamics of social and socio-semantic structures, at both macroscopic and microscopic scales, emphasizing the remarkable stability of these macroscopic properties in spite of a vivid local, agent-based network dynamics.     

The thanatic strain. Kojève and Rosenzweig as two readers of Hegel

In my essay, I focus on Alexandre Kojève’s lectures on Phenomenology of Spirit as a peculiar thanatic interpretation of Hegel. Kojève’s apology of death is so powerful that it can only suggest a new form of a religious cult, a new philosophical theology which, because of its semi-secular appearance, we should rather call a cryptotheology. I want to demonstrate that, indeed, we deal here with a cryptotheological divinisation of Thanatos where the so-called ‘frontier experience of death’ replaces the Judeo-Christian revelation. Kojève claims that this tendency already begins in Hegel in whom revelation, albeit a central notion of phenomenology, is given a characteristic, thanatico-immanentist twist. In the first part, I concentrate on Hegel and his interpretation given by Kojève; then, I present a brief overview of the thanatic strain in Kojève’s French pupils; and finally, in the second part, I return to Hegel, but his time read through the lenses of Franz Rosenzweig who dared to oppose the thanatic tendency of twentieth century philosophy. The Star of Redemption inaugurates this opposition – a distinctly modern Jewish ‘vitalistic strain’ – by returning to the original idiom of revelation and offering us a neues Denken, a ‘new thinking.’ But this new vitalism, grown out of the polemic with the ‘thanatic strain,’ does not constitute a simple repetition of the nineteenth century Lebensphilosophie; equally critical of the Kojèvian ‘overestimation of death’ and of the old forms of vitalistic thinking, it paves the way to a highly innovative late-modern philosophy of finite life which – as I will argue here – is something we very badly need today.     

Health technology assessment between our health care system and our health

In this contribution, I wish to explore the potential of health technology assessment and ethics for increasing our capacity to pre-empt the shortcomings and undesired consequences of modern health care while maintaining its benefits. Central is the presumption that in case of some health problems this cannot be done unless we explicitly reconsider some features of the modern health care system, especially those related to its strong reliance on scientific rationality and the strong role played by medical professionals. So as to both maintain the benefits of advanced health care and ensure that it produces less reason for concern, we need to reconsider our approach to rationality—and maybe even the way in which we build our health care system around that rationality. That is, we need to introduce an element of reflexivity. Two types of circumstances are being explored in which such reflexivity may prove worthwhile: controversies on side effects, and persistent problems encountered in optimising health care. Drawing on brief discussions of typical cases, we explore the potential of reflexive HTA and its methodical prerequisites. We conclude that ethicists may contribute to reflexive HTA, if they combine a hermeneutic—and often also participative—methodology with a solid understanding of the relation between the health problem under scrutiny and more general critique of the health care system. Insights from the areas of science and technology studies, as well as from social philosophy may be critical items in their tool kit.     

Data craft: a theory/methods package for critical internet studies

ABSTRACT

Disinformation campaigns continue to thrive online, despite social media companies’ efforts at identifying and culling manipulation on their platforms. Framing these manipulation tactics as ‘coordinated inauthentic behavior,’ major platforms have banned culprits and deleted the evidence of their actions from social activity streams, making independent assessment and auditing impossible. While researchers, journalists, and civil society groups use multiple methods for discovering and tracking disinformation, platforms began to publish highly curated data archives of disinformation in 2016. When platform companies reframe manipulation campaigns, however, they downplay the importance of their products in spreading disinformation. We propose to treat social media metadata as a boundary object that supports research across platforms and use metadata as an entry point for investigating manipulation campaigns.

We illustrate how platform companies’ responses to disinformation campaigns are at odds with the interests of researchers, civil society, policy-makers, and journalists, limiting the capacity to audit the role that platforms play in political discourse. To show how platforms’ data archives of ‘coordinated inauthentic behavior’ prevent researchers from examining the contexts of manipulation, we present two case studies of disinformation campaigns related to the Black Lives Matter Movement. We demonstrate how data craft – the exploitation of metrics, metadata, and recommendation engines – played a prominent role attracting audiences to these disinformation campaigns. Additionally, we offer some investigative techniques for researchers to employ data craft in their own research of the disinformation. We conclude by proposing new avenues for research for the field of Critical Internet Studies.     

On credible coalitional deviations by prudent players

In this paper we first explore the predictive power of the solution notion called conservative stable standard of behaviour (CSSB), introduced by Greenberg (The theory of social situations, 1990), in environments with farsighted players (as modelled in Xue, Econ Theory 11:603–627, 1998) as intuitively it is quite nice. Unfortunately, we find that CSSB has a number of undesirable properties: most importantly, it makes vacuous predictions for most natural social environments. Therefore, we introduce an intuitive refinement of this solution which we call conservative stable weak predictor. In settings of proper voting games, we explore some existence properties of this new solution and also show that it may not be unique. However, unfortunately, this refinement may also lead to non-intuitive vacuous predictions.