Spurios Spatial Regression: Some Monte Carlo Results with a Spatial Unit Root and Spatial Cointegration

In this paper I introduce the concepts of spatial unit roots and spatial cointegration, and via Monte-Carlo simulation I illustrate their implications for spatial regression. It is shown that spatial unit roots lead to spurious (spatial) regression, as in the well-known case involving time-series. Spatial cointegration is similar to its time-series counterpart, although I demonstrate that OLS estimation of spatial error-correction models is not consistent.     

The Antiquities Market: News and Commentary on the Illicit Traffic in Antiquities

Abstract

Wind God Foils Smuggler's Breeze through Customs

Laura Scanlan's article describing the seizure at U.S. Customs and the eventual return to Mexico of several important Precolumbian artifacts is reprinted here with permission from Customs Today, 17:2 (1982) 2–3. Both the story itself and the act of reprinting emphasize the growing cooperation between archaeologists and the U.S. Customs Bureau in cases involving antiquities. Karen Bruhns and Connie Fenchel (see below) have been an effective team in pursuing cases involving antiquities smuggling in the San Francisco area. In the Bernstein case (see below “A Lawyer Looks at U.S. Antiquities Laws”) archaeologists also provided professional evaluations and consultation to customs officials. Both the Mexican case described here by Scanlan and the Bernstein case were initiated through improper customs declarations, which were recognized by alert customs inspectors familiar with the value of antiquities and the significance of the illicit trade.

These cases suggest a way for many archaeologists who have said they would like to help curb the illicit trade but did not know how to do so. There are customs offices in most large U.S. cities. They are the places where antiquities enter this country. Special Agent Fenchel pointed out, during her presentation at the Legislative Session of the AIA in San Francisco, that most antiquities cases in this country have begun with an improper customs declaration. If this is so, the effectiveness of existing law governing the antiquities trade depends largely on the ability of customs inspectors to recognize antiquities and to evaluate their accompanying declarations. Even when/if the UNESCO Convention is implemented, its enforcement will be largely in the hands of customs inspectors. Thus, professional archaeologists could make a substantive contribution toward curbing import of illicit antiquities by introducing themselves at their local customs office and offering to make available their professional advice on cases involving antiquities. Local archaeological societies might consider offering seminars for their local customs inspectors on ancient art and archaeology and the pertinent laws and market values, to help increase the ability of customs inspectors to recognize antiquities in the course of their work. Just knowing that there is expert help available locally to identify and evaluate antiquities, or to find another expert who might be able to do so, could make local customs inspectors more sensitive to the issues involved and more likely to catch violations.     

Competition in a Repeated Spatial Auction Market with an Application to Timber Sales

In this paper we develop a model of a repeated spatial auction market. The auction model contributes to the literature on spatial competition by considering the sale of goods in a market with spatial and temporal dimensions, and in which goods are sold by an auction institution instead of a posted-price institution. In the Nash equilibrium of the spatial auction model, each bidder is found to have a dominance solvable strategy to bid below his net (of transportation costs) valuation for the first unit of the good because there is an option value to not winning, namely that the following units may be locationally preferred to the first unit. The equilibrium bidding strategies lead to the possibility of non–Pareto-efficient outcomes. The auction model is applied to data from U.S. Forest Service timber sales.     

The Interview Hurdle to Postgraduate Studies and the Job Market

Abstract

This paper explores the educational value of a rural trail—a field visit on foot—using as an example a trail in a small area of countryside near Lancaster in northern England. This trail provides those teaching rural geography in higher education with a means of developing their students’ skills of informed observation and interpretation of field evidence based on study and discussion on‐site. A trail can enhance the appreciation and teaching of conceptual matters such as cultural approaches to rural geography. It also encourages the integration of diverse theoretical approaches to rural studies (based on culture, planning and management) and the simultaneous consideration by students of both local (often personal) details and national (or even global) pressures for change. The paper concludes that the rural trail has considerable pedagogical and academic merit for rural geographers.     

Modelling of hydrology and potential population levels at Bronze Age Jawa,Northern Jordan: a Monte Carlo approach to cope with uncertainty

An annual water balance model for Wadi Rajil, in Northern Jordan, is used to simulate the ancient water supply system for the Early Bronze Age site of Jawa. The model includes: water delivery from the catchment; local pond storage; and water demand for people, animals and irrigation. A Monte Carlo approach is used to incorporate the uncertainty associated with a range of factors including rainfall, evaporation, water losses and use. The stochastic simulation provides estimates of potential population levels sustainable by the water supply system. Historical precipitation estimates from a Global Circulation Model, with uncertainty bounds, are used to reconstruct the climate at Jawa in the Early Bronze Age (EBA). Model results indicate that the population levels in the predicted wetter conditions during parts of the EBA could have risen to ∼6000 and may have been higher in wet years. However, palaeoclimatic proxies also suggest prolonged droughts in the EBA; and during these periods the water management system was unable to provide adequate supply for a population of 6000. The utility of Monte Carlo based hydrological modelling as a tool within archaeological science is discussed.     

集市:民俗学理解日常生活的新视野

集市是广泛存在于世界各地区各民族的商品交易形式,也是地方社会生活在空间上的浓缩。以流动为特征的集市为地方性知识的生成与表述、民俗关系的搭建与互动提供了场域,是区域性生活实践、文化变迁和社区整合的动力源泉。民俗学对集市中民俗事象、时空特征和实践活动的关注,可在超越村落边界的基础上,透视人群交往、文化交流和物品交换之间的关系,从而拓展民俗学的研究视野,深化对日常生活的理解,提升民俗学理论方法的活力;同时,民俗学的学术关怀可以进一步充实集市研究的生活感、文化性与应用性,丰富有关集市当代转型和乡村社会建设等议题的讨论,体现学科服务社会发展的现实关切。     

Housing Market Dynamics Under Stochastic Growth: An Application to the Housing Market in Boulder, Colorado

Recent housing-market studies have modeled slow stock and price adjustment with some success. However, the empirical procedures used in these models break down if housing stocks or prices are driven by stochastic growth. In this paper I suggest an error-correction model for analyzing housing supply and demand under conditions of stochastic growth for a regional housing market. The model is applied to the housing market in Boulder, Colorado from 1981 through 1995—a period of rapid growth in housing values in the area. Long-run housing supply and demand are shown to be inelastic with respect to changes in the price of housing. The results indicate that developers respond more accurately to housing-market disequilibrium attributable to supply-side disturbances than to disturbances generated by changes in the demand for housing. On the other hand, price appreciation is driven primarily by demand disturbances.     

Spatial Autocorrelation in Ecological Studies: A Legacy of Solutions and Myths

A major aim of including the spatial component in ecological studies is to characterize the nature and intensity of spatial relationships between organisms and their environment. The growing awareness by ecologists of the importance of including spatial structure in ecological studies (for hypothesis development, experimental design, statistical analyses, and spatial modeling) is beneficial because it promotes more effective research. Unfortunately, as more researchers perform spatial analysis, some misconceptions about the virtues of spatial statistics have been carried through the process and years. Some of these statistical concepts and challenges were already presented by Cliff and Ord in 1969. Here, we classify the most common misconceptions about spatial autocorrelation into three categories of challenges: (1) those that have no solutions, (2) those where solutions exist but are not well known, and (3) those where solutions have been proposed but are incorrect. We conclude in stressing where new research is needed to address these challenges.     

Local Spatial Autocorrelation Statistics: Distributional Issues and an Application

The statistics G_i(d) and G_i*(d), introduced in Getis and Ord (1992) for the study of local pattern in spatial data, are extended and their properties further explored. In particular, nonbinary weights are allowed and the statistics are related to Moran's autocorrelation statistic, I. The correlations between nearby values of the statistics are derived and verified by simulation. A Bonferroni criterion is used to approximate significance levels when testing extreme values from the set of statistics. An example of the use of the statistics is given using spatial-temporal data on the AIDS epidemic centering on San Francisco. Results indicate that in recent years the disease is intensifying in the counties surrounding the city.     

Reality versus Policy: The Delineation and Testing of Local Labour Market and Spatial Policy Areas

As part of the empirical planning science, this article integrates theory, empirical findings and policy. It first deals with the question how to reach a theoretically well-grounded and empirical applicable delineation of local labour market areas. An inductive classification method is selected based on the behaviour of individual commuters without selecting a priori central places. By this, new urban forms like polynodality are included. In using this method for the Netherlands, 31 local labour market areas (LLAs) were distinguished. Moreover, the article elaborates some simple measures to test the optimality of LLA classifications. The 31 LLAs adequately reflect the 'reality' of actual functional labour market relationships. The article also investigates the matching between reality and the LLA classification as used in spatial policy. There is a large gap between reality and policy. This urges bringing the policy classification more in line with existing LLAs. Alternatively, if one considers the present policy classification as an instrument for future spatial structure, much additional effort will be required. The findings of the article can be easily applied to other European countries.     

Analyzing the Relationship Between Smoking and Coronary Heart Disease at the Small Area Level: A Bayesian Approach to Spatial Modeling

We model the relationship between coronary heart disease and smoking prevalence and deprivation at the small area level using the Poisson log-linear model with and without random effects. Extra-Poisson variability (overdispersion) is handled through the addition of spatially structured and unstructured random effects in a Bayesian framework. In addition, four different measures of smoking prevalence are assessed because the smoking data are obtained from a survey that resulted in quite large differences in the size of the sample across the census tracts. Two of the methods use Bayes adjustments of standardized smoking ratios (local and global adjustments), and one uses a nonparametric spatial averaging technique. A preferred model is identified based on the deviance information criterion. Both smoking and deprivation are found to be statistically significant risk factors, but the effect of the smoking variable is reduced once the confounding effects of deprivation are taken into account. Maps of the spatial variability in relative risk, and the importance of the underlying covariates and random effects terms, are produced. We also identify areas with excess relative risk.     

Neural Network Modeling of Constrained Spatial Interaction Flows: Design, Estimation, and Performance Issues

In this paper a novel modular product unit neural network architecture is presented to model singly constrained spatial interaction flows. The efficacy of the model approach is demonstrated for the origin constrained case of spatial interaction using Austrian interregional telecommunication traffic data. The model requires a global search procedure for parameter estimation, such as the Alopex procedure. A benchmark comparison against the standard origin constrained gravity model and the two–stage neural network approach, suggested by Openshaw (1998), illustrates the superiority of the proposed model in terms of the generalization performance measured by ARV and SRMSE.     

Market Potential,Productivity and Foreign Direct Investment: Some Evidence from Three Case Studies

This paper aims at analysing the importance of local determinants to foreign direct investment (FDI) in three European regional case studies. The originality of the approach lies in the use of disaggregated data by sector and by region. The results are three-fold. First, regional demand and productivity are fundamental FDI determinants, confirming most studies with national data. Second, regional FDI inflows are more dependent on regional than national determinants. Finally, the effect of market potential measured with absolute gross domestic product (GDP) on regional FDI diminishes linearly with distance and does not when measured with GDP per capita.     

Market Rules and Spatial Outcomes: Insights from the Corporate Restructuring of U.S. Food Retailing

In this paper a study of the corporate restructuring of the U.S. food retail industry, during and following the period of regulatory relaxation and high-leverage capital transformations of the 1980s, is used to interrogate the complex relationships between market regulation, investment regimes, corporate strategies, and spatial outcomes. It is shown that changes in the “rules” governing investment and competition in the United States in the 1980s triggered countervailing spatial processes in the food retail industry. Those processes took more than a decade to work themselves through, but by the late 1990s a radically altered corporate landscape was beginning to emerge. In particular, consolidation of the industry had finally gained momentum–creating an industry whose leading firms are likely by 2002 to have a market share double the level of the early 1990s. The paper concludes by considering the insights which a consideration of corporate restructuring and regulation in this U.S. industry offers for some important areas of conceptual debate in economic geography. In particular, it is argued that industries in which capital structure transformations of the firm must be confronted and treated as a central issue have an intrinsic, but until recently neglected, importance in theoretical debate in the discipline.