Gambling in contests with random initial law

This paper studies a variant of the contest model introduced in Seel and Strack [J. Econom. Theory 148 (2013) 2033-2048]. In the Seel-Strack contest, each agent or contestant privately observes a Brownian motion, absorbed at zero, and chooses when to stop it. The winner of the contest is the agent who stops at the highest value. The model assumes that all the processes start from a common value $x_0>0$ and the symmetric Nash equilibrium is for each agent to utilise a stopping rule which yields a randomised value for the stopped process. In the two-player contest, this randomised value has a uniform distribution on $[0,2x_0]$. In this paper, we consider a variant of the problem whereby the starting values of the Brownian motions are independent, nonnegative random variables that have a common law $\mu$. We consider a two-player contest and prove the existence and uniqueness of a symmetric Nash equilibrium for the problem. The solution is that each agent should aim for the target law $\nu$, where $\nu$ is greater than or equal to $\mu$ in convex order; $\nu$ has an atom at zero of the same size as any atom of $\mu$ at zero, and otherwise is atom free; on $(0,\infty)$ $\nu$ has a decreasing density; and the density of $\nu$ only decreases at points where the convex order constraint is binding.Comment: Published at http://dx.doi.org/10.1214/14-AAP1088 in the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org

Gambling in contests with regret

This paper discusses the gambling contest introduced in Seel & Strack (Gambling in contests, Discussion Paper Series of SFB/TR 15 Governance and the Efficiency of Economic Systems 375, Mar 2012.) and considers the impact of adding a penalty associated with failure to follow a winning strategy. The Seel & Strack model consists of $n$-agents each of whom privately observes a transient diffusion process and chooses when to stop it. The player with the highest stopped value wins the contest, and each player's objective is to maximise their probability of winning the contest. We give a new derivation of the results of Seel & Strack based on a Lagrangian approach. Moreover, we consider an extension of the problem in which in the case when an agent is penalised when their strategy is suboptimal, in the sense that they do not win the contest, but there existed an alternative strategy which would have resulted in victory

Universal Behavior in Heavy Electron Materials

We present our finding that an especially simple scaling expression describes the formation of a new state of quantum matter, the Kondo Fermi liquid (KL) in heavy electron materials. Emerging at $T^*$ as a result of the collective coherent hybridization of localized f electrons and conduction electrons, the KL possesses a non-Landau density of states varying as $(1-T/T^*)^{3/2}[1+\ln(T^*/T)]$. We show that four independent experimental probes verify this scaling behavior and that for CeIrIn$_5$ the KL state density is in excellent agreement with the recent microscopic calculations of hybridization in this material by Shim, Haule, and Kotliar.Comment: 4 pages, 5 figure

The Weakest Link: A Model of the Decline of Surface Transportation Networks

This study explores the economic mechanisms behind the decline of a surface transportation network, based on the assumption that the decline phase is a spontaneous process driven by decentralized decisions of individual travelers and privatized links. A simulation model is developed with a degeneration process by which the weakest link is removed iteratively from the network. Experiments reveal how the economic efficiency of a network evolves during the degeneration process and suggest an 'optimal' degenerated network could be derived during the decline phase in terms of maximizing total social welfare. Keywords: decline, transportation network, degeneration, welfare, accessibilityNetworks, Transportation, Structure, Entropy, Pattern, Continuity

How Streetcars Shaped Suburbanization: A Granger-Casality Analysis of Land Use and Transit in The Twin Cities

This paper presents a causality analysis of the coupled development of population and streetcars in the Twin Cities metropolitan area. Historic residence and network data were assembled for 1900-1930, and linear cross-sectional time-series models were estimated at both a tract and block level using this data. It is found that, in contrast with transportation systems that were expanded in response to increased demand, the rapid expansion of the streetcar system during the electric era has been driven by other forces and to a large extent led land development in the Twin Cities. The main forces that have driven this process include technological superiority, monopoly, close con- nections with real estate business, and peopleÕs reliance on the streetcar for mobility. Proximity to the streetcar is found to be a crucial factor that determines the distribu- tion and development of residences: it is observed that residential density declines with the distance from streetcar lines, and signiÞcantly drops beyond a walkable distance; it is also observed that gaining a closer access to streetcar lines within 800 meters (about a half mile) predicts the increase in residential density to a signiÞcant extent.Transport, land use, Twin Cities (Minnesota), Streetcars, Light Rail Transit, network growth, induced demand, induced supply

Governance choice on a serial network

This paper analyzes governance choice in a two-level federation in providing road infrastructure across jurisdictions. Two models are proposed to predict the choice of centralized or decentralized spending structure on a serial road network shared by two districts. While the first model considers simple Pigouvian behavior of governments, the second explicitly models political forces at both a local and central level. Both models led to the conclusions that the spending structure is chosen based on a satisfactory comprise between benefits and costs associated with alternative decision-making processes, and that governance choice may spontaneously shift as the infrastructure improves temporally.Governance choice · Transportation · Infrastructure · Fiscal federalism

Does First Last: The Existence and Extent of First Mover Advantages on Spatial Networks

This paper examines the nature of first mover advantages on spatially-differentiated surface transportation networks. The literature on first mover advantages identifies a number of sources that explain their existence. However whether those sources exist on spatial networks, and how they play out with true capital immobility have been unanswered questions. By examining empirical examples including commuter rail and the Underground in London and roads in the Twin Cities of Minneapolis and St. Paul, first mover advantages were observed in rail stations but not in the road network. A simulation model was then constructed to replicate the growth of surface transportation networks incorporating idealized deployment decisions and to test whether the first network elements (links, nodes) remain strongest (or even strong) into the future. Simulation experiments were conducted and Spearman rank correlation tests revealed that first mover advantages exist in both nodes and links and become increasingly prominent as the network evolves due to the accumulated advantage of earlier established network elements. Simulation results also disclosed that network growth with a higher concentration of initial land uses results in stronger first mover advantages, and that the extent may vary as the topological attributes of the network change over time. The sensitivity of simulation results on model parameters are also discussed.First mover advantage, transport, land use, London Underground, London railways, network growth, induced demand, induced supply

Alexis de Tocqueville; chronicler of the American democratic experiment

[Abstract]: The purpose of this work is to develop an interactive tool which helps botanists to extract the vein system with its hierarchical properties with as little user interaction as possible. In this paper, we present a new venation extraction method using independent component analysis (ICA). The popular and efficient FastICA algorithm is applied to patches of leaf images to learn a set of linear basis functions or features for the images and then the basis functions are used as the pattern map for vein extraction. In our experiments, the training sets are randomly generated from different leaf images. Experimental results demonstrate that ICA is a promising technique for extracting leaf veins and edges of objects. ICA, therefore, can play an important role in automatically identifying living plants