IMPERFECT INFORMATION,UNCERTAINTY AND OPTIMAL SAMPLING IN LOCATION THEORY: AN INITIAL REEXAMINATION OF HOTELLING,WEBER, AND VON THÜNEN*

ABSTRACT Sophisticated locational analysis should no longer proceed without examining (1) the feasibility of reducing uncertainty about the size and spatial spread of the market, prices and other elements and (2) the practicality of information generation through sampling. The present paper points out the methodology for Hotelling-, Weberian- and von Thünen- type location problems by examining simplified situations.     

SPATIAL MONOPSONY AND MONOPOLY PRICING IN A STOCHASTIC ENVIRONMENT*

ABSTRACT. In this paper some of the important properties of the behavior of a spatial monopsonist (monopolist) facing a stochastic supply (demand) curve are derived. Under uncertainty, price setting and quantity setting behavior are no longer equivalent. Hence, spatial price discrimination has to be compared with spatial quantity discrimination with respect to expected profits. I prove three general theorems on how the ranking of the behavioral modes, in terms of expected profit, depends on how the stochastic component enters the supply (demand) and supply (demand) price functions. In particular, I prove that under monopsony one would expect a high probability of excess demand, in the sense that the firm would accept all deliveries at the preset price.     

SOLVING A THREE-DIMENSIONAL URBAN ACTIVITY MODEL OF LAND USE INTENSITY AND TRANSPORT CONGESTION*

ABSTRACT Recent developments in combining input-output and transportation planning models have made it possible to construct realistic comprehensive urban and regional activity models of land use intensity. These models form the basis for a rigorous approach to studying the interactions among urban activities. However, efficient computational solution methods for implementing such comprehensive models are still not available. In this paper, an efficient solution method for a nonlinear programming urban systems model is developed by combining Evans's partial linearization technique with Powell's hybrid method. The solution algorithm is applied to a small but realistic urban area with a detailed transportation network.     

A CONDITIONALLY PARAMETRIC PROBIT MODEL OF MICRODATA LAND USE IN CHICAGO

Spatial data sets pose challenges for discrete choice models because the data are unlikely to be independently and identically distributed. A conditionally parametric spatial probit model is amenable to very large data sets while imposing far less structure on the data than conventional parametric models. We illustrate the approach using data on 474,170 individual lots in the City of Chicago. The results suggest that simple functional forms are not appropriate for explaining the spatial variation in residential land use across the entire city.     

THE SCOPE FOR PURE PROFITS IN A STANDARD LOCATION MODEL*

ABSTRACT. This paper examines the possibility of sustaining a collusive equilibrium in a standard location model. Drawing on recent developments in game theory, it is suggested that collusion is only feasible if market areas lie within a certain range. When market areas are large the threat of entry is likely to undermine any collusive agreement. In contrast when market areas are small, defection from the cartel is shown to be profitable. Thus collusion is shown to be feasible only when market areas and demand lie within certain bounds. More generally, this result appears to be consistent with the somewhat ambiguous empirical evidence which suggests that competitive pricing behavior is likely to prevail in periods of excessively high demand and during recessions.     

LAND USE AND LAND COVER IN EASTERN CHINA: A LANDSAT ANALYSIS

Landsat imagery is a valuable source of information about the land use and land cover of inaccessible areas. In this study, the objective was to compile a map of eastern China, with particular emphasis on agricultural activity, from enhanced Landsat imagery using the diazo and density slicing techniques. Area measurement of major land uses was based on the land-use interpretation map, but because of the lack of ground verification it was necessary to turn to other sources of published and unpublished information as a control.
L'objectif de cette étude est la compilation d'une carte géographique de l'Est de la Chine, avec accentuation particulière des activités agricoles. Comme les images Landsat sont souvent la source unique d'information sur la végétation et l'utilisation de terrains inaccessibles, cette carte a éte cornpilée à l'aide d'images Landsat agrandies par les techniques diazo et density slicer. Les mesures des surfaces des régions principales sont celles de la carte d'interprétation de l'utilisation des terres. Faute d'une méthode de calibrage, il a fallu accepter les données de sources secondaires publiées et nonpubliées comme base de contrôle.     

A REGIONAL ECONOMY,LAND USE,AND TRANSPORTATION MODEL (RELU‐TRAN©): FORMULATION,ALGORITHM DESIGN,AND TESTING*

ABSTRACT RELU is a dynamic general equilibrium model of a metropolitan economy and its land use, derived by unifying in a theoretically valid way, models developed by one of the authors [ Anas (1982) , Anas–Arnott (1991, 1997) , Anas–Kim (1996) , Anas–Xu (1999) ]. RELU equilibrates floor space, land and labor markets, and the market for the products of industries, treating development (construction and demolition), spatial interindustry linkages, commuting, and discretionary travel. Mode choices and equilibrium congestion on the highway network are treated by unifying RELU with the TRAN algorithm of stochastic user equilibrium [ Anas–Kim (1990) ]. The RELU‐TRAN algorithm's performance for a stationary state is demonstrated for a prototype consisting of 4‐building, 4‐industry, 4‐labor‐type, 15‐land‐use‐zone, 68‐link‐highway‐network version of the Chicago MSA. The algorithm solves 656 equations in a special block‐recursive convergent procedure by iterations nested within loops and loops within cycles. Runs show excellent and smooth convergence from different starting points, so that the number of loops within successive cycles continually decreases. The tests also imply a numerically ascertained unique stationary equilibrium solution of the unified model for the calibrated parameters.