We provide three axiomatic characterizations of Egghe's g-index, which measures a researcher's scientific output based on the number of papers the researcher has published and the number of citations of each of the researcher's papers. We formulate six new axioms for indexes, namely, tail independence (TA), square monotonicity (SM), the cap condition (CC), strong square monotonicity (SSM), increasing marginal citations (IMC), and increasing marginal citations+ (IMC+). Along with the two well-known axioms T1 and T2 (Woeginger, 2008a), the g-index is characterized by (i) T1, T2, TA, SM, and CC, (ii) T1, T2, TA, SSM, and IMC, and (iii) T1, TA, SM, and IMC+. Two out of three characterizations are obtained by adding axioms to our new characterization of the class of indexes satisfying TI, T2, and TA, which are defined as generalizations of the g-index. Thus, the remaining four axioms in our first and second characterizations SM, CC, SSM, and IMC distinguish the original g-index from other related indexes in the class. Furthermore, the independence of our axioms and that of Woeginger's study is shown. (C) 2015 Elsevier Ltd. All rights reserved.

We examine the range of anonymity that is compatible with a Paretian social welfare relation (SWR) on infinite utility streams. Three alternative coherence properties of an SWR are considered, namely, acyclicity, quasi-transitivity, and Suzumura consistency. For each case, we show that a necessary and sufficient condition for a set of permutations to be the set of permissible permutations of some Paretian SWR is given by the cyclicity of permutations and a weakening of group structure. Further, for each case of coherence property, we show that the extended Pareto rule is the least element of the class of anonymous Paretian SWRs. (C) 2014 Elsevier B.V. All rights reserved.

We analyze the problem of a jury that must rank a set of contestants whose socially optimal ranking is common knowledge among jurors who may have friends among the contestants and may, therefore, be biased in their friends' favor. We show a natural mechanism that is finite and complete informational, with no simultaneous moves (i.e., it is solvable by backward induction), which implements the socially optimal ranking with subgame perfect equilibria. (C) 2014 Elsevier Inc. All rights reserved.

This paper shows that in private value environments, strategy-proofness and the rectangular property are necessary conditions for (full) robust implementation (Bergemann and Morris, 2011). As corollaries, we obtain the equivalence between robust and secure implementation (Saijo et al., 2007), the revelation principle for robust implementation, and characterization of double implementation in robust and secure implementation. (C) 2014 Elsevier Inc. All rights reserved.

We consider the problem of allocating multiple units of an indivisible good among a group of agents in which each agent demands at most one unit of the good and money payment or receipt is required. Under general preference domains that may contain non quasi-linear preferences, the Vickrey allocation rule is characterized by axioms for equity and continuity without use of efficiency: namely, the Vickrey rule is the only rule that satisfies strategy-proofness, weak envy-freeness for equals, non-imposition, and continuity of welfare.