Search results for "Spatial"

Nature et impacts des effets spatiaux sur les valeurs immobilières : le cas de l'espace urbanisé francilien

2013

International audience

NEIGHBORHOOD EFFECTS IN SPATIAL HOUSING VALUE MODELS. THE CASE OF THE METROPOLITAN AREA OF PARIS (1999)

2009

In hedonic housing models, the spatial dimension of housing values are traditionally processed by the impact of neighborhood variables and accessibility variables. In this paper we show that spatial effects might remain once neighborhood effects and accessibility have been controlled for. We notably stress on three sides of neighborhood effects: social capital, social status and social externalities and consider the accessibility to the primary economic center as describing the urban spatial trend. Using spatial econometrics specifications of the hedonic equation, we estimate whether spatial effects impact the housing values. Our empirical case concerns the Metropolitan Area (MA) of Paris i…

Spatial effects of urban public policies on housing values

2009

International audience; Problems of spatial segregation have often stressed on the social status and social capital of a neighbourhood as main driving forces behind housing price formation. In this paper, it is assumed that spatial effects are additional variables worth considering since the impact of urban policies such as social housing policies and urban regeneration policies may permeate outside the areas where they are implemented. Our case study is of the urban area of Dijon (France), where these two types of urban policies have been implemented in the last three decades. Spatial effects are introduced in the hedonic model and a spatial error model is estimated, revealing a positive a…

Dominància i ocupació de l'espai en grups de primats no-humans: un model basat en conducta adaptativa

2007

L'estructura jeràrquica és una de les característiques fonamentals de les societats de primats, que condiciona en gran mesura el comportament dels individus que conviuen al grup. Quines lleis regeixen la formació i l'estructura d'aquestes jerarquies? Per què en determinats grups els subjectes més dominants se situen al centre del grup i en uns altres de la mateixa espècie no? En el camp de la conducta animal s'han proposat múltiples hipòtesis, però no n'hi ha cap que siga totalment satisfactòria, ja que a causa de les múltiples variables que hi infl ueixen, és difícil desplegar una teoria que explique tota la complexitat que s'observa empíricament. La nostra proposta d'estudi es basa en l'e…

The Evolution of Territorial Occupation:

2012

International audience; The analysis of territorial changes over time raises many methodological questions. Despite a very frequent use of spatial analysis methods, few works underline their methodological shortcomings. This paper considers a comparison and discussion of exploratory statistical methods (notably Ripley's K function and its derivatives). It is worth noting three parameters in archaeological spatial analysis: scale, quality and quantity of input data. Archaeological data are intrinsically heterogeneous. Therefore, our approach proposes a multiscalar process integrating heterogeneous data. We describe a range of methods for the description and analysis of heterogeneous spatial …

Yrjö Blomstedtin ja Victor Sucksdorffin Kainuu

2016

Hyperspectral Image Classification with Kernels

2007

The information contained in hyperspectral images allows the characterization, identification, and classification of land covers with improved accuracy and robustness. However, several critical problems should be considered in the classification of hyperspectral images, among which are (a) the high number of spectral channels, (b) the spatial variability of the spectral signature, (c) the high cost of true sample labeling, and (d) the quality of data. Recently, kernel methods have offered excellent results in this context. This chapter reviews the state-of-the-art hyperspectral image classifiers, presents two recently proposed kernel-based approaches, and systematically discusses the specif…

Studying The Hydrological Response Of Urban Catchments Using A Semi-Distributed Linear Non-Linear Model

2000

A conceptual rainfall-runoff model for urban catchment, which incorporates, semi-distributed modelling concepts has been developed. In the proposed model, the catchment is divided in external sub-catchments connected to the drainage network. Each external sub-catchment is modelled as two separate conceptual linear elements, a reservoir and a channel, one for the pervious part, the other for the impervious part of the drainage area. The drainage network is schematised as a cascade of non-linear cells and the flood routing is simplified in the form of kinematic wave and represented as a flux transfer between adjacent cells. Tests carried out using data from the Parco d'Orleans experimental ca…

Representation of Autonomous Automata

2001

An autonomous automaton is a finite automaton with output in which the input alphabet has cardinality one when special reduced. We define the transition from automata to semigroups via a representation successful if given two incomparable automata (neither simulate the other), the semigroups representing the automata are distinct. We show that representation by the transition semigroup is not successful. We then consider a representation of automata by semigroups of partial transformations. We show that in general transition from automata to semigroups by this representation is not successful either. In fact, the only successful transition presented is the transiton to this semigroup of par…

Conflict in Somalia: impact on child undernutrition

2017

Background: In Somalia, protracted conflict and persistent drought have caused population displacement and livelihood destruction. As a result, there is widespread child malnutrition. We aimed to determine the effects of conflict on wasting and stunting among children aged 6-59 months in Somalia 2007–2010.\ud \ud Methods: Data were from household nutritional surveys from 2007 to 2010, with 1,066 clusters covering 73,778 children, the Armed Conflict Location and Event Data (ACLED) project and remote sensing. We used Bayesian hierarchical spatial-temporal regression methods to examine the effects of conflict on wasting and stunting. A preliminary model included individual, household and envir…