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21.
The most common indicator used to measure spatial dependence is Moran's I proposed by statistician Patrick A. P. Moran in 1950. The index is simple to use and applies the principle of the Pearson correlation coefficient, although it incorporates a proximity measure between elements. However, Moran's I tends to underestimate real spatial autocorrelation when the number of locations are few. This study aims to present a modified version of Moran's I that can measure real spatial autocorrelation even with small samples and check for spatial dependence.  相似文献   
22.
The paper discusses how the recent history of famine has influenced the mission of relief-oriented non-governmental organisations (NGOs).  相似文献   
23.
Although the issue of the out-of-plane response of unreinforced masonry structures under earthquake excitation is well known with consensus among the research community, this issue is simultaneously one of the more complex and most neglected areas on the seismic assessment of existing buildings. Nonetheless, its characterization should be found on the solid knowledge of the phenomenon and on the complete understanding of methodologies currently used to describe it. Based on this assumption, this article presents a general framework on the issue of the out-of-plane performance of unreinforced masonry structures, beginning with a brief introduction to the topic, followed by a compact state of art in which the principal methodologies proposed to assess the out-of-plane behavior of unreinforced masonry structures are presented. Different analytical approaches are presented, namely force and displacement-based, complemented with the presentation of existing numerical tools for the purpose presented above. Moreover, the most relevant experimental campaigns carried out in order to reproduce the phenomenon are reviewed and briefly discussed.  相似文献   
24.
25.

This article examines the historical processes that shaped the development of archaeological practice in Angola during the Portuguese colonial period and the aftermath of political independence. Using published works, unpublished reports, and photographic records, we examine the research themes, actors, scholars, and institutions that influenced archaeological research in the country. We also used documents and museum collections in Angola and Portugal to create a GIS database of Angola’s archaeological findings. This study highlights the events, personalities, and priorities that motivated earlier investigations, and the geographical distribution of prehistoric sites. We hope this study will be a resource for guiding future archaeological research in Angola.

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26.
This paper provides evidence about location and colocation patterns of manufacturing entrepreneurship and spatial scope of agglomeration economies in the context of a developing country. Using microgeographic data for all Brazilian manufacturing activities and distance-based measures, we find clear patterns of colocalization between entrants and existing establishments, and that these patterns occur mainly at short distances. For activities presenting colocalization between entrants and existing establishments, our results also indicate that a greater number of incumbent establishments in a given location positively affects the number of entrant establishments that decide to locate there, an effect that attenuates rapidly with distance (generally disappearing after 5 km). This pattern of attenuation is robust to both the inclusion of a comprehensive set of controls for observable and unobservable local characteristics and the use of instrumental variables to address remaining endogeneity concerns.  相似文献   
27.
U.S. immigration policy has been the subject of considerable debate in recent years. Previous research has focused on how temporal variation in federal policy has altered the migratory behavior of immigrants. The effect of spatial variation in enforcement remains untested. Relying on the criminological distinction between general and specific deterrence, we argue that high rates of enforcement are unlikely to encourage undocumented immigrants to self‐deport. We also examine the effects cultural and economic immigration policies adopted by the states. Previous research suggests that migrants will choose to remain in states with favorable environments, but this claim has not been directly tested. We draw on data from the Mexican Migration Project (MMP) to address these gaps. MMP data are supplemented with government data on federal enforcement obtained from Immigration and Customs Enforcement (ICE) and measures of state policy. Our findings suggest that higher rates of enforcement and the establishment of negative policy environments do not encourage undocumented immigrants to leave the United States at a higher rate than their documented counterparts do. Rather, high enforcement contexts exaggerate the differences between documented and undocumented migrant behavior, with undocumented migrants staying longer. Liberal state policies have no discernible effect.  相似文献   
28.
Abstract

Surpassing the national perspective usually adopted, the authors confirmed the existence of a pattern of population distribution common to the whole Iberian Peninsula in the long run. This pattern is clearly associated with geographical factors. These variables seem to have more weight in explaining changes between 1877/78 and 1940 than in the period from 1940 to 2001. The observation of the cross-border region has shown that proximity to the frontier has not generated any distinct pattern of population density on either side of the boundary line. The spatial coherence of the observed phenomena throughout the Peninsula and of its evolution, independent of the border between states, reinforces the importance of geographic factors in their explanation. At the same time, this verification opens up new issues related to the effect of national political and economic policies.  相似文献   
29.
City councils are significant, though seldom central, actors in local policy networks providing public assistance to disadvantaged residents. Mayors and council members in 12 American cities more often support than oppose public assistance initiatives. They claim that their own normative judgments are more important to their preferences and voting behavior on such matters than are public opinion, group demands, or economic considerations. While such elected officials hold a variety of justice principles, the most important of these affecting their positions on public assistance issues is the “floors” principle. A broad ethical commitment to providing social minimums enhances support for living‐wage ordinances, for linking subsidies for economic development to assistance to less advantaged citizens, and for exempting spending on social services from budget cuts. We discuss the implications of these findings for major theories of urban politics and policies—collective‐action theory, regime theory, and pluralism—and for advocates on behalf of the urban poor.  相似文献   
30.
This article discusses the relation between ethnography and underexposure of memory. Displaying similar characteristics, the ethnographies we developed in Portugal and Chile dealt precisely with this thematic in different chronological periods. We are going to point out our fieldwork convergences, specifically in what concerns the data recollection process.  相似文献   
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