Price Dynamics in the International Wheat Market: Modeling with Error Correction and Directed Acyclic Graphs

In this paper we examine dynamic relationships among wheat prices from five countries for the years 1981–1999. Error correction models and directed acyclic graphs are employed with observational data to sort–out the dynamic causal relationships among prices from major wheat producing regions: Canada, the European Union, Argentina, Australia, and the United States. An ambiguity related to the cyclic or acyclic flow of information between Canada and Australia is uncovered. We condition our analysis on the assumption that information flow is acyclic. The empirical results show that Canada and the U.S. are leaders in the pricing of wheat in these markets. The U.S. has a significant effect on three markets excluding Canada.     

Solutions and frictions in civic hacking: collaboratively designing and building wait time predictions for an immigration office

Smart and data-driven technologies seek to create urban environments and systems that can operate efficiently and effortlessly. Yet, the design and implementation of such technical solutions are full of frictions, producing unanticipated consequences and generating turbulence that foreclose the creation of friction-free city solutions. In this paper, we examine the development of solutions for wait time predictions in the context of civic hacking to argue that a focus on frictions is important for establishing a critical understanding of innovation for urban everyday life. The empirical study adopted an ethnographically informed mobile methods approach to follow how frictions emerge and linger in the design and production of queue predictions developed through the civic hacking initiative, Code for Ireland. In so doing, the paper charts how solutions have to be worked up and strategies re-negotiated when a shared motivation meets different data sources, technical expertise, frames of understanding, urban imaginaries and organisational practices; and how solutions are contingently stabilised in technological, motivational, spatiotemporal and organisational specificities rather than unfolding in a smooth, linear, progressive trajectory.     

Spatiotemporal Analysis of Surface Changes by Tessellations

This paper develops a method for analyzing the change of surface, a continuous function defined over the two‐dimensional space. The surface change is represented by a scalar field in a spatiotemporal region. The region is divided into subregions called hills and waves which are based on the local form of the surface. They are both three‐dimensional tessellations of the spatiotemporal region, and provide an overview of the surface change. To summarize the tessellations, four operations are proposed: section, projection, merging, and graph representation. They extract useful information from tessellations to describe the structure of surface change. To test the validity of the method, the change of a retail cluster in Shinjuku and Shibuya area in Tokyo is analyzed. The empirical study yields some interesting findings that help us understand changes in the spatial structure of retailing.     

An Assessment of the Causal Relationship between Growth and Inequality in Spanish Regions

This paper analyses the causal relationship between economic growth and income inequality in Spanish regions from 1970 to 2000. We examine such a relationship using a panel of data with four time observations on the level variables for each region. Thus, we use a modified form of traditional Granger causality tests to suit the short times series that are available. Applying a sum–difference test, we conclude that the empirical evidence supports the hypothesis that gross domestic product (GDP) per capita growth in Spanish regions leads to less income inequality, rather than any other possible causal relationship.     

Does Policy Diffusion Need Space? Spatializing the Dynamics of Policy Diffusion

For decades, scholars in multiple disciplines have examined spatial diffusion, or the spatiotemporal properties associated with the diffusion of innovations. These properties include contagious, hierarchical, and relocation diffusion. Each of these refers to a spatial model that epitomizes how innovations spread among geographic locations. Policy diffusion, a separate but homologous research tradition, had its theoretical underpinnings in spatial diffusion. However, contemporary policy diffusion has focused largely on mechanism‐based diffusion. This article demonstrates how exploratory spatial data analysis can be used to uncover spatial policy diffusion properties. In this study, municipal smoking regulation adoptions, religious‐based initiatives, and bag ban and bag fees are examined. This study finds evidence that for each policy more than one property is occurring; therefore, this study proposes that a hybrid model best explains diffusion. This article demonstrates how examining spatial diffusion properties, in addition to diffusion mechanisms, can improve the conceptualization of diffusion theories, enhance mechanism or theory‐based specification of diffusion models, and unravel the specific regional or neighboring causal pathways linking policies between adopting jurisdictions.     

Complex Hunter–Gatherers in Evolution and History: A North American Perspective

A review of recent research on complex hunter–gatherers in North America suggests that age-old tensions between evolutionary and historical epistemologies continue to cultivate progress in anthropological understanding of sociocultural variation. Coupled with criticism of the evolutionary status of ethnographic foragers, archaeological documentation of variation among hunter–gatherer societies of the ancient past makes it difficult to generalize about causal relationships among environment, subsistence economy, and sociopolitical organization. Explanations for emergent complexity on the Pacific Coast that privilege environmental triggers for economic change have been challenged by new paleoenvironmental findings, while hypotheses suggesting that economic changes were preceded by, indeed caused by, transformations of existing structures of social inequality have gained empirical support. In its emergent data on mound construction apart from significant subsistence change, the southeastern United States gives pause to materialist explanations for complexity, turning the focus on symbolic and structural dimensions of practice that cannot be understood apart from particular histories of group interaction and tradition. Taken together, recent research on complex hunter–gatherers in North America has not only expanded the empirical record of sociocultural formations once deemed anomalous and/or derivative of European contact but also has contributed to the ongoing process of clarifying concepts of cultural complexity and how this process ultimately restructures anthropological theory.     

Connecting climate variability and conflict: Implications for empirical testing

Quantitative research on climate variability and conflict is frequently criticized for being theoretically underdeveloped. In this article I discuss the most plausible suggested mechanisms connecting climate variability to conflict explicitly in reference to empirical testing. This approach could help solve the puzzle of how climate variability and conflict are related by highlighting how researchers can establish the key elements in the causal argument before moving on to testing it empirically. More specifically, I emphasize four key elements when evaluating each individual mechanism: first, who are the most relevant actors, second, what are the actors reacting toward (what type of climate variability), third, what conflict type is the most likely outcome, and fourth, what is the most appropriate temporal and spatial scale for each individual mechanism. Although empirical studies have moved toward more focus on theory and explicit tests of hypotheses derived from theoretical frameworks, an overview of how mechanisms are likely to manifest themselves and a discussion on how researchers can model them in analyses are missing in the research field. Adding technical fixes or new datasets to empirical testing does not automatically improve our understanding of the relationship between climate variability and conflict if the choices are not anchored in theoretical expectations.     

社会网络的空间化:以深圳传媒产业为例的社会地理网络研究

经济社会学对于经济活动所根植的社会关系网络的揭示,引发了网络思想的普遍关注。本文从经济社会学与文化经济地理学相结合的跨学科视角,探讨如何使用社会网络分析技术,将文化经济活动的地域关系网络可视化,提出"社会地理网络"的概念。论文以深圳传媒产业"大事记"作为数据来源,详细叙述了如何将影响深圳传媒产业发展历程的社会地理关系网络可视化的方法,揭示了传媒产业"社会地理网络"的存在;初步说明了社会地理网络研究的方法论意义和政策含义。     

Analyzing Hotspots of Crime Using a Bayesian Spatiotemporal Modeling Approach: A Case Study of Violent Crime in the Greater Toronto Area

Conventional methods used to identify crime hotspots at the small‐area scale are frequentist and employ data for one time period. Methodologically, these approaches are limited by an inability to overcome the small number problem, which occurs in spatiotemporal analysis at the small‐area level when crime and population counts for areas are low. The small number problem may lead to unstable risk estimates and unreliable results. Also, conventional approaches use only one data observation per area, providing limited information about the temporal processes influencing hotspots and how law enforcement resources should be allocated to manage crime change. Examining violent crime in the Regional Municipality of York, Ontario, for 2006 and 2007, this research illustrates a Bayesian spatiotemporal modeling approach that analyzes crime trend and identifies hotspots while addressing the small number problem and overcoming limitations of conventional frequentist methods. Specifically, this research tests for an overall trend of violent crime for the study region, determines area‐specific violent crime trends for small‐area units, and identifies hotspots based on crime trend from 2006 to 2007. Overall violent crime trend was found to be insignificant despite increasing area‐specific trends in the north and decreasing area‐specific trends in the southeast. Posterior probabilities of area‐specific trends greater than zero were mapped to identify hotspots, highlighting hotspots in the north of the study region. We discuss the conceptual differences between this Bayesian spatiotemporal method and conventional frequentist approaches as well as the effectiveness of this Bayesian spatiotemporal approach for identifying hotspots from a law enforcement perspective.     

Narrative strategies in a nondemocratic setting: Moscow’s urban policy debates

The Narrative Policy Framework (NPF) explains the role of narratives in policy processes. The NPF was developed for democratic contexts and has not been systematically applied in a nondemocratic setting. This study fills this gap with an empirical analysis of narrative strategies used by governmental and oppositional actors in urban policy debates in Moscow. Results show how governmental actors consistently use angel shifts, contain issues, and avoid using causal mechanisms, while actors opposing governmental policy use devil shifts, expand issues, and use intentional causal mechanisms. The findings suggest that narrative strategies differ depending on whether policy actors seek to promote policy reforms or draw attention to problems. We argue that policy actors’ objectives are a well-suited predictor for narrative strategies in both democratic and nondemocratic contexts.     

Geographical and Temporal Weighted Regression (GTWR)

Both space and time are fundamental in human activities as well as in various physical processes. Spatiotemporal analysis and modeling has long been a major concern of geographical information science (GIScience), environmental science, hydrology, epidemiology, and other research areas. Although the importance of incorporating the temporal dimension into spatial analysis and modeling has been well recognized, challenges still exist given the complexity of spatiotemporal models. Of particular interest in this article is the spatiotemporal modeling of local nonstationary processes. Specifically, an extension of geographically weighted regression (GWR), geographical and temporal weighted regression (GTWR), is developed in order to account for local effects in both space and time. An efficient model calibration approach is proposed for this statistical technique. Using a 19‐year set of house price data in London from 1980 to 1998, empirical results from the application of GTWR to hedonic house price modeling demonstrate the effectiveness of the proposed method and its superiority to the traditional GWR approach, highlighting the importance of temporally explicit spatial modeling.     

Fleshing out the geographies of social movements: Colombia's Pacific coast black communities and the ‘aquatic space’

The intersections between the concepts of space, place and resistance have recently received increasing attention from geographers dedicated to the study of social movements. Space and place are not merely seen as providing a physical background for mobilisations but as mutually constitutive of social movement agency. Yet, critics of theoretical frameworks drawn up by geographers have often rightly pointed to the lack of convincing empirical evidence presented in their support.This paper addresses these critiques by offering a theoretically informed and empirically grounded account of recent mobilisations by the social movement of black communities in the Pacific coast region of Colombia. Drawing on both the objective aspects of place and the subjective feelings that are derived from living in a place, I will show how these mechanisms have impacted on the specific spatial organising forms adopted by black communities. In particular, I will propose the concept of ‘aquatic space’ as a set of spatialised social relationships among Afro-Colombians, and show how these concrete everyday geographies have been drawn upon by black communities in the establishment of community councils along river basins.The paper argues that to make a strong point for more spatially sensitive analyses of social movements, geographers have to sustain their theoretical frameworks with concrete empirical data that not only illustrate spatial processes at play, but also convincingly demonstrate their very embeddedness in social practice. I thus argue for a strong consideration of ethnographies as a privileged research methodology to flesh out the geographies of social movements.     

Duration Modeling of Spatial Point Patterns

This paper attempts to further the research by Odland and Ellis (1992) in applying event history methodology to the analysis of spatial point patterns (that is, event patterns). Its empirical focus is the event pattern derived from the adoption of an agricultural innovation, the Harvestore, in southern Ontario, Canada, from 1963 to 1986. Event history analysis involves the use of discrete-state, continuous-time stochastic models to investigate a temporal longitudinal record on discrete variables. Event history models are usually concerned with durations of time between events and the effects of intertemporal time dependencies on future event occurrences. As such, they are often referred to as duration models. Many of the methods used in event history analysis allow the use of other nonnegative interval measurements in place of standard temporal intervals to investigate a series of events. In particular, spatial intervals (or durations) of distances between events may also be accommodated by event history models. Our analysis extends the previous research of Odland and Ellis (1992) by using a wider range of parametric models to explore duration dependence, investigating the role of spatial censoring, and using a more extensive set of explanatory variables. In addition, simulation experiments and graphical tests are used to evaluate the empirical event pattern against one generated from Complete Spatial Randomness. Results indicate that the event pattern formed by the Harvestore adopter farms is clustered (that is, is described by positive duration dependency), the sales agent is a significant factor in the distribution of adopters, and that contrasting results are obtained from the analysis using censored data versus uncensored data.     

Implications of hydro-political dependency for international water cooperation and conflict: Insights from new data

Hydro-political dependencies between countries are widely regarded as having important implications for international water cooperation and conflict. Quantitative ex-post empirical research on the subject so far uses very simple characterizations of international river geography to proxy for such dependencies, though. The authors developed a new geo-spatial dataset for water catchments worldwide. This dataset combines elevation models, flow accumulation approaches, hydrological data, and data on international boundaries to generate more precise and nuanced measures of hydro-political dependencies among riparian countries. The paper discusses these measurement concepts, illustrates how dependencies are distributed worldwide, and revisits three prominent quantitative studies on the issue to show how using improved data affects empirical findings. In contrast to a very popular presumption, upstream–downstream dependencies turn out to have a very small to insignificant effect on international water cooperation or conflict.     

项目驱动型会展专业人才培养模式研究——以上海师范大学会展经济与管理专业为例

会展专业人才培养模式是一个院校对于会展办学的整体设计,因而需要进行系统性的构建,但目前这方面的研究成果不多,更缺乏实证性的研究。本文基于文献综述的发现和会展专业的特点,从理论上构建了一个项目驱动型会展专业人才培养模式的基本框架。进而以上海师范大学会展经济与管理专业为例,侧重从教育理念、培养目标、培养过程、培养制度和培养评价等方面进行了实证研究。     

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.     

UNCERTAINTY AND THE HISTORY OF IDEAS

Intellectual historians often make empirical claims, but can never know for certain if these claims are right. Uncertainty is thus inevitable for intellectual historians. But accepting uncertainty is not enough: we should also act on it, by trying to reduce and report it. We can reduce uncertainty by amassing valid data from different sources to weigh the strengths and weaknesses of competing explanations, rather than trying to “prove” an empirical claim by looking for evidence that fits it. Then we should report our degree of certainty in our claims. When we answer empirical questions in intellectual history, we are not telling our readers what happened: we are telling them how strong we think our evidence is—a crucial shift of emphasis. For intellectual historians, then, uncertainty is subjective, as discussed by Keynes and Collingwood; the paper thus explores three differences between subjective and objective uncertainty. Having outlined the theoretical basis of uncertainty, the paper then offers examples from actual research: Noel Malcolm's work shows how to reduce and report uncertainty about composition, and David Wootton's work shows how to reduce and report uncertainty about beliefs.     

From town to town: how commercial travel connected manufacturers and markets during the industrial revolution

Positioning itself with regards to debates on the role of regionalization in the industrial revolution and on consumer and retailing revolutions, this paper uses the records of John Shaw, hardware factor of Wolverhampton, to examine how commercial travel created real spatial interactions across the industrializing economy of northern England in the period 1810–15. The paper argues that by integrating production and consumption, commercial travel played a vital part in advancing and reconciling the concurrent but apparently conflicting processes of economic regionalization and economic integration that characterized the period. Empirically, the paper contributes original data indicating concrete patterns of interaction across the space economy of early nineteenth century northern England in terms of both ‘routes’ and the intensity of interactions. The empirical material also allows for discussion of customer identities, the structure of geographically dispersed commodity chains and regional variations, if any, the nature of customer relationships.     

Drivers of (in)equity in collaborative environmental governance

Collaborative environmental governance seeks to engage diverse stakeholders to tackle complex challenges efficiently, sustainably, and equitably. However, mixed empirical evidence underscores a need to understand the conditions under which particularly equity is or is not achieved. Here, we use the empirical case of California Sustainable Groundwater Management to quantify the extent to which vulnerable small and rural drinking water users' needs are addressed in collaborative groundwater planning. Drawing on a diverse array of mixed method data, we then employ Boosted Regression and Classification Trees (BRCT) to assess potential driving factors including collaboration, representation, elite capture, stakeholder engagement, and problem severity/salience. We find each to be influential, highlighting their relevance for equitable planning. We also find evidence that these relationships are complex and outcome specific. Nonetheless, the overall effect on the three equity measures is modest at best. More institutional analysis of collaborative governance regimes from diverse contexts is needed to build a comprehensive understanding of how to meaningfully advance social and environmental equity in such decentralized reforms. Based on our results, we suggest the answer, if there is one, may transcend current focal domains such as stakeholder representation and engagement.