Theoretical and empirical studies have generally weighed the effect of peer punishment and pool punishment for sanctioning free riders separately. However, these sanctioning mechanisms often pose a puzzling tradeoff between efficiency and stability in detecting and punishing free riders. Here, we combine the key aspects of these qualitatively different mechanisms in terms of evolutionary game t...

A cryptographic primitive or a security mechanism can be specified in a variety of ways, such as a condition involving a game against an attacker, construction of an ideal functionality, or a list of properties that must hold in the face of attack. While game conditions are widely used, an ideal functionality is appealing because a mechanism that is indistinguishable from an ideal functionality...

Although threshold key-recovery systems for the discrete log based cryptosys-tems such as the ElGamal scheme have been proposed by Feldman and Pedersen 6, 11, 12], no (practical) threshold key-recovery system for the factoring based cryptosystems such as the RSA scheme has been proposed. 1 This paper proposes the rst (practical) threshold key-recovery systems for the factoring based cryptosyste...

Village Savings and Loan Associations and Self-Help Groups have the features of both a borrowing and a savings technology. They may therefore bring together savers and borrowers, increasing financial intermediation in villages with low access to formal banking. On the other hand, such intermediation may be impeded by limited liability, or by broader social frictions. To test for evidence of int...

In recent years, PUF-based schemes have not only been suggested for the basic tasks of tamper sensitive key storage or the identification of hardware systems, but also for more complex protocols like oblivious transfer (OT) or bit commitment (BC), both of which possess broad and diverse applications. In this paper, we continue this line of research. We first present an attack on two recent OTan...

In a paper from EuroCrypt’99, Damg̊ard, Kilian and Salvail show various positive and negative results on constructing Bit Commitment (BC) and Oblivious Transfer (OT) from Unfair Noisy Channels (UNC), i.e., binary symmetric channels where the error rate is only known to be in a certain interval [γ..δ] and can be chosen adversarily. They also introduce a related primitive called PassiveUNC. We pro...

A commitment scheme is a two-phase cryptographic protocol between two parties, a sender and a receiver, satisfying the following constraints. At the end of the Commit phase the sender is committed to a specific value (often a single bit) that he cannot change later on (Commitments are binding) and the receiver should have no information about the committed value, other than what he already knew...

abstract the aim of the present study was to investigate the relationship between organizational commitment and job burnout among iran football league referees. in this descriptive-correlation study, 122 referees and assistant referees of iran football leagues in season 2012-2013 participated voluntarily. organizational commitment scale (allen and meyer, 1991) and maslach and jackson burnout in...

With the introduction of template protection techniques, privacy and security of biometric data have been enforced. Meeting the required properties of irreversibility, i.e. avoiding a reconstruction of original biometric features, and unlinkability among each other, template protection can enhance security of existing biometric systems in case tokens are stolen. However, with increasing resolut...