Beyond Moran's I: Testing for Spatial Dependence Based on the Spatial Autoregressive Model

The statistic known as Moran's I is widely used to test for the presence of spatial dependence in observations taken on a lattice. Under the null hypothesis that the data are independent and identically distributed normal random variates, the distribution of Moran's I is known, and hypothesis tests based on this statistic have been shown in the literature to have various optimality properties. Given its simplicity, Moran's I is also frequently used outside of the formal hypothesis-testing setting in exploratory analyses of spatially referenced data; however, its limitations are not very well understood. To illustrate these limitations, we show that, for data generated according to the spatial autoregressive (SAR) model, Moran's I is only a good estimator of the SAR model's spatial-dependence parameter when the parameter is close to 0. In this research, we develop an alternative closed-form measure of spatial autocorrelation, which we call APLE , because it is an approximate profile-likelihood estimator (APLE) of the SAR model's spatial-dependence parameter. We show that APLE can be used as a test statistic for, and an estimator of, the strength of spatial autocorrelation. We include both theoretical and simulation-based motivations (including comparison with the maximum-likelihood estimator), for using APLE as an estimator. In conjunction, we propose the APLE scatterplot, an exploratory graphical tool that is analogous to the Moran scatterplot, and we demonstrate that the APLE scatterplot is a better visual tool for assessing the strength of spatial autocorrelation in the data than the Moran scatterplot. In addition, Monte Carlo tests based on both APLE and Moran's I are introduced and compared. Finally, we include an analysis of the well-known Mercer and Hall wheat-yield data to illustrate the difference between APLE and Moran's I when they are used in exploratory spatial data analysis.     

The affordable housing,transportation, and food nexus: Community gardens and healthy affordable living in Calgary

This study examining community gardens in Calgary was initiated in collaboration with the non-profit organization, Sustainable Calgary, as part of their housing-transportation-food nexus initiative. The main research objectives were to determine the socio-economic demographics of neighbourhoods that support community gardens and the proximity of community gardens to active transportation and public transit. Methods included the use of GIS visualization and quantitative analyses to investigate relationships between demographic variables of neighbourhoods that support community gardens, as well as the accessibility of active transit routes and Light Rail Transit stations. Findings show that community garden neighbourhoods are located in neighbourhoods with significantly fewer visible minorities, higher levels of educational attainment, and more attached dwellings such as apartments and townhomes. The average distance of community gardens from a major bike lane is 330 m, while the average distance from a Light Rail Transit station is 1.78 km. This study suggests potential inequities that may be present within the proliferation of public community gardens based on socio-economic factors other than economic capital. This paper concludes with a discussion surrounding implications and recommendations to further the equitable expansion of community gardens.     

Shift Work,Childcare and Domestic Work: Divisions of labour in Canadian paper mill communities

The growing prevalence of shift work and non-standard working hours is challenging many taken-for-granted notions about family and household life. This article examines how rotating shift schedules shape household strategies with regard to childcare and unpaid domestic work. In 1993-94 in-depth interviews were conducted with 90 predominantly male newsprint mill-workers and their spouses living in three communities located in different regions of Canada. The analysis in this article is based on these interviews as well as data collected in a questionnaire survey administered to a much larger sample. The article focuses on the effects of rotating shifts and the extent to which household strategies differ between households with one or two wage-earners. The findings reveal that the onus for adjusting to shifts fell mainly on the spouses of mill-workers, who felt constrained in their own choices regarding employment and childcare by the demanding regimen of their partner's shift schedules. In the vast majority of households a traditional division of labour predominated with regard to both childcare and domestic work. When women quit paid employment to accommodate the schedules of shift-workers and ensure time for the family to be together, traditional values reassert themselves. Surprisingly, a high level of satisfaction with current shift schedules was found, despite the significant adjustments to family life they had necessitated. By comparing families employed in the same industry but living in three very different communities, the analysis underscores the importance of local circumstances in mediating the strategies households deploy in coping with shift work, especially with regard to childcare.     

Envisioning Capitalism: Geography and the Renewal of Marxian Political Economy

This paper offers a reinterpretation of what critical theorist Moishe Postone calls 'the fundamental core of capitalism'. In so doing, it seeks to lay a set of theoretical foundations for a renewed Marxian political economy in geography, at a time when Marxism has been eclipsed as a leading critical paradigm within the discipline. The argument works on two fronts simultaneously. On the one hand, the ongoing hegemony of economic and political neo-conservatism is occluding the violent realities of a capitalist world economy behind the anodyne logics of free-market theory. These realities suggest the continued relevance of, and need for, a strong Marxian critique of political economy. But on the other hand, Marxism has been reprimanded by its erstwhile allies on the Left of geography for being too 'modern' and too capital- and class-centred. In light of this double challenge, the paper seeks to develop a 'both/and' Marxism for geography that can chart a third way between the antinomies of modern and after-modern modes of theorizing capitalism and class. A project of 'envisioning capitalism' is suggested on this basis, which combines the 'power' of modern theory with the epistemological reflexivity of after-modern theory. At the same time, capitalism and class are rethought at an ontological level and shown still to be essential features of the fin-de-millennium world, but far less closed and hegemonic than is suggested by modern modes of Marxism. Finally, a return to a class politics of redistribution is suggested, but in a way that draws in more recent Left geographical concerns with identity, difference and recognition.