Search results for "interaction models"
showing 8 items of 8 documents
Muons in air showers at the Pierre Auger Observatory: Measurement of atmospheric production depth
2014
The surface detector array of the Pierre Auger Observatory provides information about the longitudinal development of the muonic component of extensive air showers. Using the timing information from the flash analog-to-digital converter traces of surface detectors far from the shower core, it is possible to reconstruct a muon production depth distribution. We characterize the goodness of this reconstruction for zenith angles around 60° and different energies of the primary particle. From these distributions, we define Xμmax as the depth along the shower axis where the production of muons reaches maximum. We explore the potentiality of Xμmax as a useful observable to infer the mass compositi…
Interactions, spillovers de connaissance et croissance des villes européennes. Faut-il préférer la géographie, le climat institutionnel ou les réseau…
2013
Knowledge spillovers within urban economies are also sources of spillovers between cities. We examine how knowledge spillovers influenced the economic growth of 82 European metropolises over the 1990-2005 period. We model knowledge spillovers between cities on the basis of five specific interaction patterns based on geography, networks of multinational firms in advanced services, institutional climate and two combinations of these factors. Spatial models are estimated to detail the effects of growth factors in terms of spillovers and externalities. We show that spillovers are local rather than global and that interactions among cities accelerate the convergence process based on gross value …
Productivity analysis of Latvian companies using ORBIS database
2021
International audience; This research study uses ORBIS microdata at the company level to analyse productivity of 167 thousand economically active Latvian companies over 2011-2018. The aim of the study is twofold-to find factors consistently associated with productivity at the company level; and to recommend possible criteria for companies to receive a state support (from the view of enhancing aggregate productivity in the long term). Our research results show that productivity of Latvian companies is positively related to their size, age, as well as location closer to Riga and other big cities. However, there is a substantial within-group variation in productivity between companies. Multiva…
Disentangling Housing Supply to Shift towards Smart Cities: Analysing Theoretical and Empirical Studies
2022
The search for a pleasant home has concerned people ever since. Paradoxically, people are facing strong difficulties in finding a decent place to settle their lives in cities. As such, the housing market regained momentum in connection with the development of Smart Cities, where life quality of residents is strongly emphasized. Well-being in the metropolis is affected by a wide variety of factors with housing supply being among the most important, hence stirred by financing costs, construction costs, vacancy rate, sales delay, inflation rate, housing stock, price of agricultural land, and regulation. The present article reviews empirical studies on housing supply for a better understanding …
Muons in air showers at the Pierre Auger Observatory
2015
We present the first hybrid measurement of the average muon number in air showers at ultrahigh energies, initiated by cosmic rays with zenith angles between 62° and 80°. The measurement is based on 174 hybrid events recorded simultaneously with the surface detector array and the fluorescence detector of the Pierre Auger Observatory. The muon number for each shower is derived by scaling a simulated reference profile of the lateral muon density distribution at the ground until it fits the data. A 1019eV shower with a zenith angle of 67°, which arrives at the surface detector array at an altitude of 1450 m above sea level, contains on average (2.68±0.04±0.48(sys))×107 muons with energies large…
Bacheliers, étudiants et jeunes diplômés : quels systèmes migratoires régionaux ?
2006
Since French Society enters the so-called “Economy of knowledge”, migrations of young people, especially these concerning higher education graduates, are of most interests. Despite the fact that it could help to understand relations between University and work market and ways regions can evolve, the study of migrations of young people was not yet done. A set of results highlights first the main role of French capital region. It shows also main similarities and differencies of migratories' behavior.
Development of silent reading fluency and reading comprehension across grades 1 to 9 : unidirectional or bidirectional effects between the two skills?
2022
Purpose This study examines the developmental interplay between silent reading fluency and reading comprehension from Grade 1 to Grade 9 (age 7 to 15) in a large Finnish sample (N = 2,518). Of particular interest was whether the associations are bidirectional or unidirectional. Methods Children’s silent reading fluency and reading comprehension skills were assessed using group-administered tests, at seven time points, in Grades 1, 2, 3, 4, 6, 7, and 9. A random intercept cross-lagged panel model with latent factors was used to identify between- and within-person associations between silent reading fluency and reading comprehension. The use of latent factors allowed for the controlling of me…
Simulating and assessing prospective scenarios
2008
The first part of the paper is centered on the phenomena of urban growth, in order to set the rules for a sustainable scenario of urban development. Then we enter the core of the paper that is the comparison of models. For each of the three compared models, we describe its main theoretical characteristics, the chosen parameters, and the obtained results. In section 6, heterogeneity of the produced results is discussed, and we highlight the points of interest and the lacks of the three models. Here we show that results we obtained feed debates about urban growth management. Finally, concluding remarks at the end of the paper address the general topic of the evaluation of the quality of simul…