Only the Final Outcome Matters: Persistent Effects of Efforts in Dynamic Moral Hazard

We analyze a dynamic principal-agent problem in which the agent's effort in each period has strong persistent effects. We show that a simple contract, where the reward depends only on the final outcome, is explained as the optimal contract derived in the principal's optimization problem. The paper also discusses that the optimality of such a simple payment scheme crucially depends on the first-order stochastic dominance of the final outcome under various effort sequences.

All-Pay Auctions with Handicaps

An all-pay auction in which the winner is determined according to the sum of the bid and the handicap, the latter of which is endowed to the players, is analyzed. The bidding strategy in an equilibrium is explicitly derived as a "piecewise affine transformation" of the equilibrium strategy in the all-pay auction without handicaps. Allocation rule implemented in the equilibrium and revenue comparison are also discussed.

Efficiency versus Economy of Time in Multi-Unit Descending Auction: The Role of "Mari"at Flower Markets in Japan

The auctioning rule in Japanese flower markets is a slightly modified version of that of the original Dutch flower auction. At Japanese flower markets, there is an additional stage, called "mari", where buyers who lost in the previous auction can apply for purchasing the remainder of flowers at the same price as in the previous auction. We investigate the role of "mari" in multi-unit descending auction, and show that "mari" extensively speeds up the market procedure at the cost of sufficiently small loss of efficiency, compared to the original Dutch sequential auction.

Only the Final Outcome Matters : Persistent Effects of Efforts in Dynamic Moral Hazard

January 2010, Revised June 2010, Secondly revised May 201

Spatiotemporal Variation in Space Use by Eastern Wild Turkeys in Mississippi

Spatiotemporal variation in animal space use is critical for understanding how individual animals respond to changes in resource availability across space and time. My study was aimed to: 1) determine functional responses of habitat selection by eastern wild turkeys (Meleagris gallopavo silvestris) across 7 study sites in Mississippi; and 2) determine the effect of temporal vegetation variation on order-II habitat selection by wild turkeys over 12 years. I developed resource selection functions using radio telemetry location data. Individual-specific coefficients of order-III habitat selection for forest were related inversely to forest availability in meta-regressions. Yearly coefficients of order-II habitat selection for forest were related inversely to the mean normalized difference vegetation index (NDVI) in April, but the coefficients for open fields were related positively to coefficient of variation in the NDVI from March to May. Wild turkeys exhibited functional responses of habitat selection to spatiotemporal forest availability across Mississippi

Excitons and biexcitons in symmetric electron-hole bilayers

Symmetric electron-hole bilayer systems have been studied at zero temperature using the diffusion quantum Monte Carlo method. A flexible trial wave function is used that can describe fluid, excitonic and biexcitonic phases. We calculate condensate fractions and pair correlation functions for a large number of densities rs and layer separations d. At small d we find a one-component fluid phase, an excitonic fluid phase, and a biexcitonic fluid phase, and the transitions among them appear to be continuous. At d = 0, excitons appear to survive down to about rs = 0.5 a.u., and biexcitons form at rs > 2.5 a.u.Comment: 5 pages, 4 figure

Phenotypic change of macrophages in the progression of diabetic nephropathy; sialoadhesin-positive activated macrophages are increased in diabetic kidney

Inflammatory process is involved in pathogenesis of diabetic nephropathy, although the activation and phenotypic change of macrophages in diabetic kidney has remained unclear. Sialoadhesin is a macrophage adhesion molecule containing 17 extracellular immunoglobulin-like domains, and is an I-type lectin which binds to sialic acid ligands expressed on hematopoietic cells. The aim of this study is to clarify the activation and phenotypic change of macrophages in the progression of diabetic nephropathy. We examined the expression of surface markers for pan-macrophages, resident macrophages, sialoadhesin, major histocompatibility complex class II and alpha-smooth muscle actin in the glomeruli of diabetic rats using immunohistochemistry at 0, 1, 4, 12, and 24 weeks after induction of diabetes by streptozotocin. Expression of type IV collagen and the change of mesangial matrix area were also measured. The mechanism for up-regulated expression of sialoadhesin on macrophages was evaluated in vitro. The number of macrophages was increased in diabetic glomeruli at 1 month after induction of diabetes and the increased number was maintained until 6 months. On the other hand, sialoadhesin-positive macrophages were increased during the late stage of diabetes concomitantly with the increase of alpha-smooth muscle actin-positive mesangial cells, mesangial matrix area and type IV collagen. Gene expression of sialoadhesin was induced by stimulation with interleukin (IL)-1 beta and tumor necrosis factor-alpha but not with IL-4, transforming growth factor-beta and high glucose in cultured human macrophages. The present findings suggest that sialoadhesin-positive macrophages may contribute to the progression of diabetic nephropathy