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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Spatial interaction and local government expenditures for functionally impaired in Sweden

Birkelöf, Lena January 2009 (has links)
The thesis consists of an introductory part and three self-contained papers. Paper [I] studies the determinants of the differences in expenditure on services for functionally impaired individuals among municipalities in Sweden. A spatial autoregressive model is used in order to test whether the decisions on the expenditure level in a neighboring municipality affect the municipality’s own expenditure. The results show of spatial interaction among neighbors, possible due to mimicking. However, when controlling for differences among counties there is no evidence of spatial interaction. Therefore, the positive interaction first found can be interpreted either as a result of differences in the way county councils diagnose individuals or due to interaction among the neighbors in the same county. Paper [II] takes advantage of a new intergovernmental grant in two ways. First, the grant is used to study the effect on municipal spending related to the grant. Second, the grant is used to test a hypothesis of spatial interaction among municipalities due to mimicking behavior. The data used pertains to the periods before and after the introduction of the grant. A fixed-effects spatial lag model is used to study the spatial interactions among municipalities. The results show that before the grant, municipalities interact with their neighbors when setting the expenditure level, while there is no evidence of interaction in the second period. This would support the hypothesis that the grants provide information to the municipalities and the need for mimicking diminishes with the grant. Paper [III] examines whether local public expenditures on services to functionally impaired individuals crowd out other local public expenditures in Sweden. The hypothesis is tested on five different spending areas using a two-stage least squares (2SLS) fixed-effects model. While the results give no support for crowding out in the areas of social assistance, culture & leisure, and childcare & preschool, a negative relationship on spending for elderly & disabled care and on spending for education is found, suggesting that crowding out indeed occurs within the municipal sector. The negative relationships are significant both in a statistical and an economic sense.
12

Exploring spatial interactions

Bruner, Ryan David 08 August 2012 (has links)
The field of interaction design is constantly shifting with the introduction of new technologies that allow individuals the ability to interact with or act upon an environment, such as installations that use motion tracking as an input device, or allowing users to interact with an environment with their mobile device. This shift from the interaction with traditional computers (static machines) to machines that react to people and environments, requires designers to reevaluate how these new platforms can be effectively used to communicate information and have a lasting affect on participants. There is a great challenge in the articulation of new interaction models. Many people tend to hold on to more traditional or familiar methods of interacting with their devices, as these new methods of engagement require the learning of new metaphors for interaction. How do we construct systems that engage and motivate people to use unfamiliar systems? The work presented in this report is my attempt to answer this question by exploring emerging spatial interface technologies. / text
13

Spatial econometric methods for modeling origin destination flows

LeSage, James P., Fischer, Manfred M. 11 1900 (has links) (PDF)
Spatial interaction models of the gravity type are used in conjunction with sample data on flows between origin and destination locations to analyse international and interregional trade, commodity, migration and commuting patterns. The focus is on the classical log-normal model version and spatial econometric extensions that have recently appeared in the literature. These new models replace the conventional assumption of independence between origin-destination flows with formal approaches that allow for spatial dependence in flow magnitudes. The paper also discusses problems that arise in applied practice when estimating (log-normal) spatial interaction models. (authors' abstract)
14

A New Era of Spatial Interaction: Potential and Pitfalls

January 2017 (has links)
abstract: As urban populations become increasingly dense, massive amounts of new 'big' data that characterize human activity are being made available and may be characterized as having a large volume of observations, being produced in real-time or near real-time, and including a diverse variety of information. In particular, spatial interaction (SI) data - a collection of human interactions across a set of origins and destination locations - present unique challenges for distilling big data into insight. Therefore, this dissertation identifies some of the potential and pitfalls associated with new sources of big SI data. It also evaluates methods for modeling SI to investigate the relationships that drive SI processes in order to focus on human behavior rather than data description. A critical review of the existing SI modeling paradigms is first presented, which also highlights features of big data that are particular to SI data. Next, a simulation experiment is carried out to evaluate three different statistical modeling frameworks for SI data that are supported by different underlying conceptual frameworks. Then, two approaches are taken to identify the potential and pitfalls associated with two newer sources of data from New York City - bike-share cycling trips and taxi trips. The first approach builds a model of commuting behavior using a traditional census data set and then compares the results for the same model when it is applied to these newer data sources. The second approach examines how the increased temporal resolution of big SI data may be incorporated into SI models. Several important results are obtained through this research. First, it is demonstrated that different SI models account for different types of spatial effects and that the Competing Destination framework seems to be the most robust for capturing spatial structure effects. Second, newer sources of big SI data are shown to be very useful for complimenting traditional sources of data, though they are not sufficient substitutions. Finally, it is demonstrated that the increased temporal resolution of new data sources may usher in a new era of SI modeling that allows us to better understand the dynamics of human behavior. / Dissertation/Thesis / Doctoral Dissertation Geography 2017
15

Implementace prostorových interakčních modelů v prostředí GIS / Implementation of spatial interaction models in GIS environment

Mattern, Tomáš January 2015 (has links)
The main aim of this paper is to propose a methodology for implementation of spatial interaction models in the GIS environment. This methodology is then verified by creating functional tool for calculating potential accessibility model. The first part summarizes the available literature about those issues. The second part presents the source data and analysis methodology. ESRI ArcGIS and Python are main technologies used. Subsequently, a description of creation tool itself. In conclusion the test analyses and results are described and discussed. Powered by TCPDF (www.tcpdf.org)
16

Exploring affordances of tangible user interfaces for interactive lighting

Bijman, Nicolaas Peter January 2019 (has links)
This paper explores interaction with lighting through a tangible user interface (TUI). In a TUI the physical object and space around it are part of the interface. A subset of tangible interaction called spatial interaction is the main focus of this paper. Spatial interaction refers to translation, rotation or location of objects or people within a space. The aim of this paper is to explore the relation between spatial inputs and lighting outputs based on different design properties. A user test is set up to explore the effect that design properties of a TUI have on the lighting output that participants map to spatial inputs. The results of the conducted user test indicate that communicating affordances to the user is an important factor when designing couplings between spatial inputs and lighting outputs. The results further show that the shape of the interface plays a central role in communicating those affordances and that the overlap of input and output space of the interface improves the clarity of the coupling. / Den här studien utforskar gripbar (tangible) interaktionsdesign med fokus på ljus och belysning. Vid användning av ett gripbart (tangible) gränssnitt används den fysiska miljön som gränssnitt. Detta skiljer sig till stor del från interaktion med ett grafiskt användargränssnitt, där alla interaktioner sker och begränsas av en skärms egenskaper. Denna studie fokuserar på rumslig (spatial) interaktionsdesign, vilket är en del av gripbar interaktionsdesign. Rumslig interaktion refererar till översättning, rotation eller plats av objekt eller människor i ett utrymme. Ett användartest har utförts för att testa vad för effekt olika rumsliga indata och designegenskaper har på förväntad utdata för ljus och belysning. Resultatet från användartestet visar att starka affordances och begränsningar, tillsammans med överlappningen av rumslig indata och utdata för ljus och belysning, är de viktigaste egenskaperna för att designa tydliga övergångar.
17

Modeling Politics Among Nations as Spatial Interaction: Explaining the Diplomatic Relations of the United States 1980-2000 with Spatial Regression

Xierali, Imam M. January 2006 (has links)
No description available.
18

Examining Commuting Patterns and Spatial Mismatch by Occupation and Gender: Disaggregate Journey-to-Work Model

Sang, Sunhee 11 February 2009 (has links)
No description available.
19

Barriers to cross-region research and development collaborations in Europe. Evidence from the fifth European Framework Programme

Fichet de Clairfontaine, Aurélien, Fischer, Manfred M., Lata, Rafael, Paier, Manfred 11 1900 (has links) (PDF)
The focus of this paper is on cross-region R&D collaboration funded by the 5th EU Framework Programme (FP5). The objective is to measure distance, institutional, language and technological barrier effects that may hamper collaborative activities between European regions. Particular emphasis is laid on measuring discrepancies between two types of collaborative R&D activities, those generating output in terms of scientific publications and those that do not. The study area is composed of 255 NUTS-2 regions that cover the pre-2007 member states of the European Union (excluding Malta and Cyprus) as well as Norway and Switzerland. We employ a negative binomial spatial interaction model specification to address the research question, along with an eigenvector spatial filtering technique suggested by Fischer and Griffith (2008) to account for the presence of network autocorrelation in the origin-destination cooperation data. The study provides evidence that the role of geographic distance as collaborative deterrent is significantly lower if collaborations generate scientific output. Institutional barriers do not play a significant role for collaborations with scientific output. Language and technological barriers are smaller but the estimates indicate no significant discrepancies between the two types of collaborative R&D activities that are in focus of this study. (authors' abstract) / Series: Working Papers in Regional Science
20

Análise espacial da produção e das redes de colaboração científica no Brasil: 1990-2010 / Spatial analysis of scientific production and collaboration networks in Brazil: 1990-2010

Sidone, Otávio José Guerci 25 November 2013 (has links)
O crescimento acelerado da produção científica brasileira nos anos recentes foi acompanhado pela expansão das colaborações científicas domésticas. Neste estudo, olhamos mais atentamente esse assunto na tentativa pioneira de identificar padrões espaciais da produção e colaboração científica no Brasil, e avaliar o papel da proximidade geográfica na determinação das interações entre os pesquisadores brasileiros. Por meio de uma base única composta por mais de um milhão de pesquisadores registrados na Plataforma Lattes e de sete milhões de publicações científicas, coletamos e consolidamos informações sobre as colaborações científicas inter-regionais em termos de redes de coautorias entre 1.347 municípios brasileiros ao longo do período compreendido entre 1990 e 2010, o que permitiu uma abrangência de dados e perspectiva de análise inéditas na literatura. Os efeitos da distância geográfica nas redes de colaboração são mensurados para as diferentes áreas do conhecimento por meio da estimação de modelos de interações espaciais. Os principais resultados sugerem fortes evidências de um processo de desconcentração espacial da produção científica nos últimos anos associado à expansão das redes de colaboração e ao aumento da participação de autores das regiões cientificamente menos tradicionais, tais como Sul e Nordeste. Ademais, também encontramos evidência de que a distância ainda desempenha papel crucial na determinação da intensidade dos fluxos de conhecimento nas redes de colaboração científica no Brasil, embora a magnitude do efeito varie entre as redes das diferentes áreas do conhecimento. Por exemplo, verificamos que o distanciamento de 200 quilômetros entre dois pesquisadores implica na redução média de 22% ou 45% na probabilidade de haver colaboração entre eles, caso eles sejam de Linguística, Letras e Artes ou Ciências Exatas e da Terra, respectivamente. / Recent years have witnessed an accelerated growth of Brazilian scientific production that was accompanied by an expansion of domestic research collaboration. In this paper we look more closely at this issue in a pioneering attempt to identify spatial patterns of research production and collaboration in Brazil, and to measure the role of geographical proximity in determining interaction between Brazilian researchers. Using a unique database comprised of over one million researchers registered in the Brazilian Lattes Platform and seven million scientific publications, we collect and consolidate information on interregional research collaboration in terms of co-authorship networks among 1,347 Brazilian cities over the period between 1990 and 2010, which enabled a range of data and analysis perspective unprecedented in literature. The effects of geographical distance on research collaboration are measured for different knowledge areas under the estimation of spatial interaction models. The main results suggest strong evidence of spatial de-concentration of scientific production in the last years with expansion of research collaboration networks and an increased participation of authors in scientifically less traditional regions, such as South and Northeast. Moreover, we also find evidence that distance still plays a crucial role in determining the intensity of knowledge flows in scientific collaboration networks in Brazil, although the magnitude of such effects varies among networks of different knowledge areas. For instance, we found that the distancing of 200 kilometers between two researchers implies an average reduction of 22% or 45% on probability of collaboration among them, if they are of Linguistics, Letters and Arts or Exact and Earth Sciences, respectively.

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