Publications

Does it pay off for companies to disclose voluntary commitments to their customers? While voluntary commitments to enhance customers’ benefits became prevalent in many markets, systematic evidence on how customers (if at all) reward companies, which disclose such discretionary kindness, is still lacking. We analyze the consequences of endogenous disclosure of discretionary kindness in a novel experiment (N = 636). We model the decision situation in a bilateral reciprocity game with asymmetric information on the vol-untariness of kindness. Experimental data show that endogenously disclosing discretionary kindness significantly triggers rewards from customers and does not backfire. Findings are robust towards variations in costs of information and the level of customers’ benefits. Survey evidence from a vignette study support our behavioral findings.

We experimentally study the causal effect of being an immigrant or previously convicted on the hiring preferences and wage payments of employers. We find evidence for statistical discrimination against immigrants. Criminal offenders suffer from more severe and taste discrimination.

In a monetarily incentivized Dictator Game, we expected Dictators’ empathy toward the Recipients to cause more pro-social allocations. Empathy was experimentally induced via a commonly used perspective taking task. Dictators (N = 474) were instructed to split an endowment of 10€ between themselves and an unknown Recipient. They could split the money 8/2 (8€ for Dictator, 2€ for Recipient) or 5/5 (5€ each). Although the empathy manipulation successfully increased Dictators’ feelings of empathy toward the Recipients, Dictators’ decisions on how to split the money were not affected. We had ample statistical power (above 0.99) to detect a typical social psychology effect (corresponding to r around 0.20). Other possible determinants of generosity in the Dictator Game should be investigated.

The organization of collective action is extremely important for societies. A main reason is that many of the key problems societies face are public good problems. We present results from a series of laboratory experiments with large groups of up to 100 subjects. Our results demonstrate that large groups, in which the impact of an individual contribution ( MPCR ) is almost negligible, are able to provide a public good in the same way as small groups in which the impact of an individual contribution is much higher. Nevertheless, we find that small variations in MPCR in large groups have a strong effect on contributions. We develop a hypothesis concerning the interplay between MPCR and group size, which is based on the assumption that the salience of the advantages of mutual cooperation plays a decisive role. This hypothesis is successfully tested in a second series of experiments. Since Mancur Olson’s “Logic of collective action” it is a commonly held belief that in large groups the prospects of a successful organization of collective actions are rather bad. Our results, however, suggest that the chance to successfully organize collective action of large groups and to solve important public good problems is much higher than previously thought.

Recent studies have demonstrated that the right dorsolateral prefrontal cortex (rDLPFC) and the right temporoparietal junction (rTPJ) are causally involved in social norm compliance. Here, we tested the hypothesis that a third party's decision to punish norm violations depends on the activity of the entire rDLPFC/rTPJ network. We used transcranial direct current stimulation (tDCS) to independently or jointly modulate rTPJ and rDLPFC activity during the third-party dictator game. We found a significant effect of anodal tDCS of the rTPJ, which decreased the third-party punishment of moderately unfair splits. Joint stimulation of the rTPJ (by anodal tDCS) and rDLPFC (by cathodal tDCS) produced a marginal effect on third-party punishment.

In the commentary to Jens Mammen’s book A New Logical Foundation for Psychology (2017), three issues are discussed. The first one concerns possible interrelations of: (a) others’ irreplaceability and existential irretrievability rigorously proved by Mammen; and (b) morality and attitudes to the others. Lem’s criticism of Heidegger’s existential philosophy, which paradoxically ignores mass homicide, is discussed in the context of topology of being. Different attitudes to the other as irreplaceable and irretrievable (e.g., in case of apprehension and execution of a murderer) are analyzed. The second issue concerns the possibility of true duplicates of the same person. The paradox of copied complexity is introduced. The third issue concerns reductionism (including brain reductionism) and opportunities to deduce various phenomena of development (mental development, actual genesis of creative thinking, etc.) from the new logical foundation for psychology built by Mammen.

In this paper we examine the effects of valence in a continuous spatial voting model with two incumbent candidates and a potential entrant. All candidates are rank-motivated. We first consider the case where the low valence incumbent (LVC) and the entrant have zero valence, whereas the valence of the high valence incumbent (HVC) is positive. We show that a sufficiently large valence of HVC guarantees a unique equilibrium, where the two incumbents prevent the entry of the third candidate. We also show that an increase in valence allows HVC to adopt a more centrist policy position, while LVC selects a more extreme position. We also examine the existence of equilibrium for the cases where the LVC has higher or lower valence than the entrant.

We set up a laboratory experiment to investigate systematically how varying the magnitude of outside options—the payoffs that materialize in case of a bargain- ing breakdown—of proposers and responders influences players’ demands and game outcomes (rejection rates, payoffs, efficiency) in ultimatum bargaining. We find that proposers as well as responders gradually increase their demands when their respec- tive outside option increases. Rejections become more likely when the asymmetry in the players’ outside options is large. Generally, the predominance of the equal split decreases with increasing outside options. From a theoretical benchmark perspective we find a low predictive power of equilibria based on self-regarding preferences or inequityaversion.However,proposers and responders seem to be guided by the equity principle, while they apply equity rules inconsistently and self-servingly.

We set up a laboratory experiment to investigate systematically how varying the magnitude of outside options—the payoffs that materialize in case of a bargaining breakdown—of proposers and responders influences players’ demands and game outcomes (rejection rates, payoffs, efficiency) in ultimatum bargaining. We find that proposers as well as responders gradually increase their demands when their respective outside option increases. Rejections become more likely when the asymmetry in the players’ outside options is large. Generally, the predominance of the equal split decreases with increasing outside options. From a theoretical benchmark perspective we find low predictive power of equilibria based on self-regarding preferences or inequity aversion. However, proposers and responders seem to be guided by the equity principle while they apply equity rules inconsistently and self-servingly.

Dishonest behavior significantly increases the cost of medical care provision. Upcoding of patients is a common form of fraud to attract higher reimbursements. Imposing audit mechanisms including fines to curtail upcoding is widely discussed among health care policy-makers. How audits and fines affect individual health care providers' behavior is empirically not well understood. To provide new evidence on fraudulent behavior in health care, we analyze the effect of a random audit including fines on individuals' honesty by means of a novel controlled behavioral experiment framed in a neonatal care context. Prevalent dishonest behavior declines significantly when audits and fines are introduced. The effect is driven by a reduction in upcoding when being detectable. Yet, upcoding increases when not being detectable as fraudulent. We find evidence that individual characteristics (gender, medical background, and integrity) are related to dishonest behavior. Policy implications are discussed.

The degree of individual manipulability of majoritarian aggregation procedures is evaluated for the case of one-dimensional positioning of alternatives and agents. The calculation of the degree of manipulability is performed for 3-5 alternatives. We find that the group of rules dominates all others in terms of the lowest share of all manipulable profiles, and for some extensions gives even the zero level manipulability.

The paper is focused on the history and modern practices of creating and applying interactive exploratory objects and worlds that provoke curiosity in the individual and require exploration and experimentation to learn them and to achieve practical goals. The development, use and demonstration of a wide range of exploratory objects (play, educational, psycho-diagnostic, etc.) in various fields reflects an increasingly wide spread belief: one of the basic human abilities that is needed now and will be in demand in the future is the ability to cope with novelty, including through active exploration and experimentation. Five interrelated directions for the development and popularization of exploratory objects are identified: science; educational practice; assessment; game practices; and literature, art, official and unofficial journalism. Parameters of specially developed interactive exploratory objects and worlds in the context of preparing for encounters with novelty and complexity are discussed. The triangle of tests of intelligence, creativity and exploratory behavior in the space of regulation – freedom is presented. Two types of motivational challenges when exploring new objects are described: exploration for the sake of the very process of cognition and exploration for the sake of desired practical effects. The issue of features of exploratory objects that stimulate posing and solving epistemic problems rather than pragmatic problems, and vice versa, is raised. In conclusion, possible reasons for the mass development and supply of exploratory objects and worlds are formulated.

The intransitive cycle of superiority is characterized by such binary relations between A, B, and C that A is superior to B, B is superior to C, and C is superior to A (i.e., A>B>C>A—in contrast with transitive relations A>B>C). The first part of the article presents a brief review of studies of intransitive cycles in various disciplines (mathematics, biology, sociology, logical games, decision theory, etc.), and their reflections in educational materials. The second part of the article introduces the issue of intransitivity in elementary physics. We present principles of building mechanical intransitive devices in correspondence with the structure of the Condorcet paradox, and describe five intransitive devices: intransitive gears; levers; pulleys, wheels, and axles; wedges; inclined planes. Each of the mechanisms are constructed as compositions of simple machines and show paradoxical intransitivity of relations such as “to rotate faster than”, “to lift”, “to be stronger than” in some geometrical constructions. The article is an invitation to develop teaching materials and problems advancing the understanding of transitivity and intransitivity in various areas, including physics education.

In the problem of aggregation of rankings or preferences of several agents, there is a well-known result that reasonable social ranking is not strategy-proof. In other words, there are some situations when at least one agent can submit insincere ranking and change the final result in a way beneficial to him. We call this situation manipulable and using computer modelling we study 10 majority relation-based collective decision rules and compare them by their degree of manipulability, i.e. by the share of the situation in which manipulation is possible. We found that there is no rule that is best for all possible cases but some rules like Fishburn rule, Minimal undominated set and Uncovered set II are among the least manipulable ones.

The majority of social and economic interactions take place between people of different social status. Age, position, income and other factors affect the way people evaluate their position in the society. We investigate how self-estimation of the social status is formed when an individual participates in an economic experimental game. In our experiment subjects are set in pairs and play consequently the dictator game, the trust game and the labor market (contract) game. After each game we measure their subjective socioeconomic status using two different scales. We show that participation in the dictator game affects the perception of one's social status to the greatest extent: the status of dictators is higher than the status of recipients. Prescription of roles in other games does not have such an effect. Active behavior, gender, income, etc. also affect the subjective status.