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161.
AGGREGATION ERROR EFFECTS ON THE DISCRETE-SPACE p-MEDIAN MODEL: THE CASE OF EDMONTON, CANADA 总被引:2,自引:0,他引:2
The spatial analysis literature recognizes three sources of aggregation error, termed Source A, Source B, and Source C, which affect models relying on distance measurements between populations and facilities. We consider these effects with respect to aggregating from census enumeration areas to census tracts, on a popular location model. We identify a further source of aggregation error, which we dub Source D error, arising from the representation of facility sites by discrete points. Source D effects are of the same magnitude as Source A and B combined, much greater than Source C effects. Source D error is further significant, because, unlike Source A and B error, it can be eliminated only by disaggregating .
La littérature sur Vanalyse spatiale reconnaît trois sources d'erreur d'agrégation appelées erreurs de source A, B, et C. Ces erreurs influencent les modèles qui reposent sur des mesures de distance entre des populations et des installations. On considère les effets d'agrégation des secteurs de dénombrement en secteurs de recensement sur un modèle de localisation courant. On identifie une quatrième source d'erreur d'agrégation appelée erreur de source D. Cette erreur découle de la représentation des sites des installations par des points discrets. Ses effets sont du même ordre de grandeur que ceux des sources A et B combinées et beaucoup plus grands que les effets de source G. L'erreur de source D est d'autant plus significative à cause du fait que, contrairement aux erreurs de source A et B, elle ne peut être éliminée que par la désagrégation . 相似文献
La littérature sur Vanalyse spatiale reconnaît trois sources d'erreur d'agrégation appelées erreurs de source A, B, et C. Ces erreurs influencent les modèles qui reposent sur des mesures de distance entre des populations et des installations. On considère les effets d'agrégation des secteurs de dénombrement en secteurs de recensement sur un modèle de localisation courant. On identifie une quatrième source d'erreur d'agrégation appelée erreur de source D. Cette erreur découle de la représentation des sites des installations par des points discrets. Ses effets sont du même ordre de grandeur que ceux des sources A et B combinées et beaucoup plus grands que les effets de source G. L'erreur de source D est d'autant plus significative à cause du fait que, contrairement aux erreurs de source A et B, elle ne peut être éliminée que par la désagrégation . 相似文献
162.
The repeated failure to design and appropriately target policies and interventions which address the needs of rural peoples in Africa suggests that something may be wrong with our understanding of the way that these peoples live their lives. Perspectives which focus on intra-household processes, and on gender issues in particular, represent useful advances in the way that the social and economic lives of Africa's rural peoples are conceptualized. However, this article questions the value of adopting development planning, policy and project approaches based on the rigid identification of `gender roles'. By reference to field research undertaken in northern Ghana, the paper aims to demonstrate that other social constructs, such as marital status and seniority, may be as important as gender in determining the roles and status of individuals in African rural societies. The article concludes by highlighting a number of practical implications of this finding in terms of the structuring of development-oriented research and the targeting of policy and interventions. 相似文献
163.
M. H. Suryanarayana 《Development and change》1997,28(4):771-789
Although assessments by conventional macro measures show considerable improvement in food security in India, the levels of cereal consumption and calorie intake of even the general population are still below the normative threshold limits. This article brings out the dynamics of changes in institutional and production conditions and their implications for consumption patterns and food security at the micro level. The article uses empirical evidence to raise a number of issues, and calls for emphasis on investment in human capital by way of improvements in food and calorie intake for efficiency and economic growth. 相似文献
164.
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166.
Renée M. Bonzani 《Journal of archaeological science》1997,24(12):1129-1139
The diversity and ubiquity measures of archaeological macrobotanical remains can be utilized to help define mobility strategies of hunter–gatherers. Differences in the diversity and ubiquity of plant remains are predicted to occur between different types of sites utilized by hunter–gatherers. Such sites include base camps of residentially and logistically mobile groups, as well as special-purpose sites usually associated with logistically mobile groups. The focus upon the importance of strategies of mobility and plant use instead of the typological determination of plant taxa allows for the use of specimen types in such analyses when scientific identifications are difficult to make. Data from the archaeological site of San Jacinto 1, located in northern Colombia, are utilized to examine this relationship. 相似文献
167.
Julia M. Asher-Greve 《Gender & history》1997,9(3):432-461
Linguistic, art historical, hermeneutic, gender and intercultural analyses clarify body and gender concepts in Sumerian and Akkadian mythology, literature and visual arts. The body was a fundamental point of reference in ancient Mesopotamia, metaphor for the total self, royal ideology, cities, humanity and deities. Humanity was created without gender; sex, gender and social status were subsequently inscribed on the body. Gender taxonomy tolerated ambiguity beyond the ‘normative’ masculine/feminine. Body and mind were an inseparable unity and denoted by the same Sumerian word. Mind/body and male/female dichotomy were unknown. 相似文献
168.
Teresa M. Shaw 《Gender & history》1997,9(3):579-596
Shaw explores the connections between dietary theory, Christian ascetic fasting, gender and the ideology of virginity in late antiquity, especially as represented in the fourth-century treatise on virginity by Basil of Ancyra. With its remarkable attention to the practicalities of embodiment and sexual renunciation, Basil’s treatise is distinctive in its genre. After discussing Basil’s treatise of creation, the nature of male and female sexual attraction and physiology, the control of bodily passions and the value of ascetic fasting for reducing desire, Shaw sets these topics in the context of ancient medical theory, gender and the theology of paradise. 相似文献
169.
170.
Latham MC 《Africa today》1993,40(3):39-53
Issues surrounding the spread of acquired immunodeficiency syndrome (AIDS) in Africa are summarized. Subjects considered include the disease's origins, proportion of the population infected with the human immunodeficiency virus (HIV) and AIDS, the problems in caring for children orphaned by the disease, innovations in drug treatments discovered by African scientists, the spread among women, and the difficulties inherent in incorporating Western-based policy and aid provisions into the African context. 相似文献