Reconciling and translating migration data collected over time intervals of differing widths

In this paper we describe and contrast the age and spatial structures of migration identified by data collected over one-year and five-year time intervals, by focusing, in particular, on the generation and distribution components of age- and origin-destination-specific migration flows. We explore the contributions of primary, return, and onward migration defined by fixed interval migration data, and we outline a crude translation procedure for transforming the one-year migration flow data into an estimated five-year counterpart. The data used in this study represent several migration periods drawn from recent U.S. and Canadian censuses and surveys. Differences between the structures exhibited by U.S. and Canadian migration patterns, collected over one-year and five-year migration time intervals, are carefully examined and contrasted. Versions of this paper were presented in February, 2002 at the annual meetings of the Western Regional Science Association in Monterey, California and in May, 2002 at the annual meetings of the Population Association of America in Atlanta, Georgia. The authors would like to thank Professor Frans Willekens at the University of Groningen in the Netherlands for his collaboration on earlier work that focused on migration spatial structure, of which this paper is a continuation. Also, our appreciation goes to the three anonymous reviewers for their comments and suggestions. This research is being supported by a grant from the National Science Foundation (BCS-9986203).     

Independent and linked migration: Individual return of employment opportunity and household return of poverty status to African American interstate migration

The thrust of this study is to describe and contrast the determinants and outcomes of African-American interstate migration. We examine two types of migration outcomes – individual return to employment probability and household level return to poverty status. We investigate these motivations and outcomes based on a new typology of migration through the lens of household change that accompanies migration. We specify a pairwise two-stage probit model incorporating individual and state-level variables using Public Use Micro Sample data and various ecological data in the US. We show that independent migrants move to other states envisioning economic models of migration with migration as a derived response to opportunities, pressures, and constraints imposed by spatial inequalities in socioeconomic development. On the other hand, we demonstrate that linked migrants move to other states also for their economic need, but via kinship. In this case, the linked migrants' path does not follow the general pattern of economic circumstances. We show that household composition is an important factor that influences the destination choice for African Americans. While independent migrants are more concerned with diverse economic conditions at destinations, kinship, other ties and household structure at destinations are more significant factors for linked migrants. Received: June 2000/Accepted: June 2001     

城市居住综合体及其对城市空间结构的调整作用

在世纪转折的今天 ,城市居住综合体作为城市住宅的一种 ,在改变着城市面貌的同时 ,也在改变着城市的空间结构。文章首先介绍了城市居住综合体这一特殊的居住建筑模式 ,进而对城市居住综合体与城市空间结构的关系进行了研究。通过对城市空间结构认识的回顾与展望 ,指出城市需要更加开放、复杂、连续的空间结构。文章还对我国城市空间结构的发展现状 ,特别是住宅建设对其的影响作了分析 ,认为城市居住综合体在调整城市空间结构方面大有可为 ,而这也正是城市居住综合体作为一种特殊形式存在的合理性之一。     

Modelling residential location choice in an area with spatial barriers

A model is presented for residential location choice in rural areas with spatial barriers. We address the problem through comparative static analysis focusing on how residential location choices are affected by a new road link across the spatial barrier. We proceed through a probability theoretical approach: choose a family of utility functions representing every possible location, and equip this family with a probability measure. Then choose a representative within an equivalence class of utility functions, and represent the probability distribution by a parametrized family of distributions. Our analysis demonstrates that investments in new road links do not necessarily represent an adequate instrument for achieving ambitions in regional policy. We identify reasonable situations where a new road link could just as easily generate net migration from the area in which the investments are directed. In general, our analysis demonstrates how agglomeration and centralisation tendencies can be considerably affected by transportation infrastructure innovations. Received: June 1999/Accepted: June 2001 This paper benefited from comments by Bj?rn Sandvik and Lars-G?ran Mattsson.     

What about aging in regional science?

This paper is a revised version of a North American Regional Science Council Presidential Address delivered at the 57th North American Meetings of the Regional Science Association International, Denver, Colorado, November 11, 2010. The question ‘What about aging in regional science?’ is posed and discussed from three perspectives. First, the aging of the corpus of practitioners of the multidisciplinary field is considered. Second, views are expressed about how, as each of us individually ages, participation in the temporal and spatial web of the regional science community helps to structure and impart meaning to our professional lives. Third, it is argued that age and aging deserve more attention as regional science research continues to advance. The implications of aging for research in the author’s specialty area of migration are discussed.     

Modelling regional migration in China: estimation and decomposition

"In this paper I consider the issue of identifying the effects of spatial structure and the origin and destination attributes on interregional migration. A decomposition approach is developed based on migration models. The interprovincial migration data in China over the period 1985-1990 are used to estimate a gravity migration model, an extended gravity model, a Poisson gravity model, and a multilevel Poisson model, which are then used to decompose the various effects on migration in China."     

Population dynamics and ethnic geographies in Oslo: the impact of migration and natural demographic change on ethnic composition and segregation

This paper explores demographic processes behind ethnic geographies in Oslo. We compare data for census tracts in 2001 and 2011, and decompose ethnic composition and segregation on local mobility, national migration, international migration and natural demographic change. The study comprises five national groups: Poles, Somalis, Sri Lankans, Iraqis and Pakistanis, plus aggregates for Nordic and non-Nordic residents. A key observation is that local mobility weakens the status of original settlements without a corresponding effect on levels of ethnic segregation. For several groups, local mobility increases both own-group exposure and separation from the Nordic majority. International migration, in contrast, increases spatial integration between Nordic and non-Nordic residents. Natural change accords with our expectation and strengthens both minority representation in established eastern settlements and ethnic segregation in Oslo at large. Certain features of the Oslo context, e.g. lack of multi-ethic experiences, domination of owner-occupied dwellings and redistributive policies, may explain the surprising results.     

弦支结构体系概念与分类

"弦支结构"明确定义了结构的各组成部分和特点:"弦"指结构下部犹如弓弦的拉索;"支"指结构中部起到支撑作用的压杆;"结构"是指弦支结构上部的具体结构形式。在介绍结构概念的基础上,将弦支结构分为平面型弦支结构、可分解的空间型弦支结构和不可分解的空间型弦支结构;提出弦支网架、弦支混凝土楼盖、弦支筒壳和弦支拱壳结构;结合相关研究成果,给出3种命名分类方案;建议将此类结构体系统一称为弦支结构体系,并按照结构概念明确和体系系统完整的原则对此类结构形式进行分类。     

城市空间分异探讨

当前我国城市空间分异产生的主要原因有：城市功能结构的转变加速了社会分层;国际资本和技术的引人产生产业布局空间分异;人口自由迁徙、流动加快了城市空间的分异;城市建设加速了城市物质环境空间的分异。城市空间分异的解决手段有社区建设、城市规划等。     

Economic-demographic models for forecasting interregional migration

"A class of spatial economic-demographic forecasting models is proposed. The models combine elements of traditional Markov and economic gravity models. A base-period probability structure is modified by the changing relative distribution of economic opportunity. Estimation issues are addressed, and an empirical application to US interstate migration during the late 1970s is described. It is contended that the framework represents a merger of past demographic and economic modeling traditions in a spatial interaction framework."     

The tuition fee ‘shock’: Analysing the response of first‐year students to a spatially discontinuous policy change in Germany

Using the introduction of tuition fees at German public universities as an exogenous shock, this paper investigates its causal impact on the enrolment and migration decision of high‐school graduates. Specifically, we conduct a quasi‐experimental analysis by exploiting the spatial and temporal variation in tuition fee regimes as a result of a Federal Constitutional Court decision. Our empirical results show that the introduction of tuition fees had a particular impact on student migration. We observe three effects: first, male students show a stronger migration response compared to female students. Second, changes in migration behaviour are sensitive to geographical distance. Finally, comparing different types of higher education institutions, we find that the migration effect is larger for universities compared to technical colleges and colleges of arts or music.     

Profiling work motivation of project workers

The purpose of this study is to understand the constructs of work motivation in project-based organizations. We first juxtapose work motivation in traditional and project-based organizations to put forward an operational definition of work motivation for our study. We then present the research methodology where we profile work motivation as perceived by project workers using principal component analysis. We obtain a five factor structure of work motivation. Finally, we discuss these results by putting them within the project management perspective and suggest managerial implications.     

中国空间结构的发展与展望

论文阐述了我国空间结构的发展概况,结构类型和形式繁多,且不断创新,需要采用按单元组成方法来分类空间结构。21世纪后,我国空间结构的发展又进入一个崭新阶段,应用范围和领域不断扩大,除在体育场馆、航站楼等大跨度公共建筑中大量采用外,在新建大型铁路客站、无站台柱雨篷、桥梁结构工程和高层建筑结构中也获得创新应用。空间结构工程的国际合作方面,应以积极态度对待国外建筑方案屡屡中标我国空间结构工程的现象。由于多项空间结构之“最”在中国,表明中国已是空间结构大国,现正是加快迈向空间结构强国的最佳时机。展望中国的空间结构,提出了应着力关注和研究的问题。图41表8参19     

空间异质性视角下的零售商业空间集聚及其影响机制研究 ——以长沙市为例

商业聚集及其影响要素具有明显的空间异质性,对其客观规律进行研讨应是商业地理学研究的重要内容,也是开展城市商业网点规划与科学管理的必然要求,但对于该问题的研究仍十分欠缺.以我国中部中心城市长沙为例,运用GWR模型对零售商业空间集聚影响要素的空间异质性进行剖析.研究表明:①长沙市仍保持"市级—区域性—社区级"的商业空间结构...     

Spatial scale, return and onward migration, and the Long-Boertlein index of repeat migration

Abstract.  Long and Boertlein's (1990 ) measure of repeat migration can be used to infer the effects of repeat migration with data sets that did not specifically ask questions about such migration. While recent work by Rogers et al. (2003 ) evaluated how well this synthetic measure matched empirical fixed-interval measures, the role of spatial scale remains unclear, particularly since scale influences migration levels, spatial structure, and the representation of the primary, return, and onward migration components within the overall flow. Motivated by the implementation of the American Community Survey and the concurrent need to adjust data from one to five-year formats, and using the 1996 Canadian Public Use Microdata File and a custom tabulation from the 1996 Canadian census, the accuracy of the index is evaluated. In particular, the effects of spatial scale upon measures of primary, return and onward migration are described and evaluated, with the Long-Boertlein measure contrasted with fixed-interval measures of return and onward migration. Results show that the measure is sensitive to spatial scale.     

传统建筑空间的有限与无限

从传统空间观念、空间构成等方面探讨了传统建筑如何在有限的空间尺度界定中去思考无限的空间价值的问题，并指出这种空间观念对现代建筑空间观的影响。     

The importance of place of birth in migration and population redistribution analysis

"In this paper, U.S. Census data is used to examine further the importance of place of birth on migration streams and to trace the impacts of such 'native dependence' on age patterns of migration, multiregional life expectancies, and spatial population projections."     

关于延边朝鲜族村落的空间结构变化研究

本研究通过现场调查,选定一个研究对象地,并根据空间结构的定义,对村落的整体空间、空间要素及各空间要素之间的相互关系分3个阶段进行分析和比较,得出其变化要因.为今后更合理地进行朝鲜族村落的规划和建设提供借鉴.     

A micro-simulation model of firms: Applications of concepts of the demography of the firm

Recently, there is an increasing demand in spatial planning for models based on the demographic concepts of birth and death of firms. This article describes the structure of a spatial demographic simulation model of firms, and its application within The Netherlands. The model structure is essentially of the familiar demographic cohort component type, where an initial cohort of firms ages in a number of discrete steps, and where in each step additions and subtractions to and from the population are modelled using birth, death and migration components. Apart from the central processes of birth, death and migration, the type of economic activity and firm size are highly important for understanding firm behaviour over time. The article describes the transition functions for each of the demographic components and for firm growth. In addition, some empirical results are presented of a number of model simulations in The Netherlands. The results were partly validated using observed economic demographic data. It is concluded that a substantial amount of work remains to be done in this new field. The model presented here has direct implications for the research agenda of the study of the demography of the firm. Received 28 April 1999 / Accepted 6 December 1999