In this paper, we characterize all interior and boundary equilibria of the GrovesLedyard mechanism for a large class of economies and demonstrate their stability or lack thereof. We prove that the mechanism implements large numbers of inefficient and stable boundary equilibria, one for each of the efficient, asymmetric, interior equilibria found by Bergstrom, Simon, and Titus (BST). We show tha...

We study whether we can weaken the conditions given in Reny [4] and still obtain existence of pure strategy Nash equilibria in quasiconcave normal form games, or, at least, existence of pure strategy ε−equilibria for all ε > 0. We show by examples that there are: 1. quasiconcave, payoff secure games without pure strategy ε−equilibria for small enough ε > 0 (and hence, without pure strategy Nash...

We study turn-based quantitative multiplayer non zero-sum games played on finite graphs with reachability objectives. In such games, each player aims at reaching his own goal set of states as soon as possible. A previous work on this model showed that Nash equilibria (resp. secure equilibria) are guaranteed to exist in the multiplayer (resp. two-player) case. The existence of secure equilibria ...

Multi-object auctions differ in an important way from single-object auctions. When bidders have multi-object demand, equilibria can exist in which bids decrease as values increase! Consider a model with n bidders who receive affiliated one-dimensional types t and whose marginal values are non-decreasing in t and strictly increasing in own type ti. In the first-price auction of a single object, ...

We study how the structure of the interaction graph of a game affects the existence of pure Nash equilibria. In particular, for a fixed interaction graph, we are interested in whether there are pure Nash equilibria arising when random utility tables are assigned to the players. We provide conditions for the structure of the graph under which equilibria are likely to exist and complementary cond...

A particular game-theoretic model (Grafen, 1990) of the evolutionary stability of honest signalling, which attempts a formal proof of the validity of Zahavi's (1975, 1977) handicap principle, is generalised and rendered as an evolutionary simulation model. In addition to supporting new theoretical results, this allows the eeects of diiering initial conditions on the attainability of signalling ...

We present theoretical models of the composition, the relative abundances, and the stability of hydrated salts on the surface and in the icy shell of Jupiter’s satellite Europa and discuss whether those salts have an oceanic origin. The evaluations were done with thermodynamic calculations of (1) salt dehydration equilibria at the conditions of the surface of Europa and its icy shell, (2) chemi...

the removal of copper (ii), zinc (ii), and chromium (iii) from wastewater by carrot residues(cr) was investigated to evaluate cation exchange capacity. the effects of solution ph and co- ions werestudied in batch experiments. adsorption equilibria were initially rapidly established, and then decreasedmarkedly after 10 min. column experiments were carried out in a glass column filled with cr toe...

this paper deals with a delayed ratio-dependent functional response predator-prey model with a threshold harvesting policy. we study the equilibria of the system before and after the threshold. we show that the threshold harvesting can improve the undesirable behavior such as nonexistence of interior equilibria. the global analysis of the model as well as boundedness and permanence properties a...