Search results for " Statistics"

Tourism statistics and unobserved tourism: empirical evidences in Sicily

2013

Despite its strategic importance, accurately measuring visitor attendance has been a challenging and problematic exercise for tourism managers for decades. Consequently, the primary aim of tourism statistics of accurately quantify tourism flows has been only partially achieved; indeed at a lower territorial scale tourism statistics appear less precise and accurate. The aim of this paper is: to introduce the concept of unobserved tourism, by highlighting the main limits of official statistical systems (with a special focus on the European statistical system on tourism statistics; to formalize a theoretical model in which tourism nights and trips in a given destination are decomposed intoobse…

Tourism statistics and unobserved tourism: empirical evidences in Sicily

2013

Despite its strategic importance, accurately measuring visitor attendance has been a challenging and problematic exercise for tourism managers for decades. Consequently, the primary aim of tourism statistics of accurately quantify tourism flows has been only partially achieved; indeed at a lower territorial scale tourism statistics appear less precise and accurate. The aim of this paper is: to introduce the concept of unobserved tourism, by highlighting the main limits of official statistical systems (with a special focus on the European statistical system on tourism statistics; to formalize a theoretical model in which tourism nights and trips in a given destination are decomposed into obs…

Geostatistical computing of acoustic maps in the presence of barriers

2009

Acoustic maps are the main diagnostic tools used by authorities for addressing the growing problem of urban acoustic contamination. Geostatistics models phenomena with spatial variation, but restricted to homogeneous prediction regions. The presence of barriers such as buildings introduces discontinuities in prediction areas. In this paper we investigate how to incorporate information of a geographical nature into the process of geostatistical prediction. In addition, we study the use of a Cost-Based distance to quantify the correlation between locations.

Multivariate approaches to behavioral physiology

2017

Bone marrow-derived progenitors are greatly reduced in patients with severe COPD and low-BMI.

2009

Chronic obstructive pulmonary disease (COPD) patients have reduced circulating hemopoietic progenitors. We hypothesized that severity of COPD parallels the decrease in progenitors and that the reduction in body mass index (BMI) could be associated with more severe bone marrow dysfunction. We studied 39 patients with moderate to very severe COPD (18 with low-BMI and 21 with normal-BMI) and 12 controls. Disease severity was associated to a greater reduction in circulating progenitors. Proangiogenetic and inflammatory markers correlated with disease severity parameters. Compared to normal-BMI patients, low-BMI patients showed: greater reduction in circulating progenitors; higher VEGF-A, VEGF-C…

Can we ascertain that an archeological site contains intentional stellar alignments?

2021

We study the different parameters that support the presence of intentional stellar alignments on an archaeological site. We develop a rigorous criterion to quantify the probability of fortuitous orientation on a starrise or a starset. We show that the magnitude of the considered stars and the precision of the angular measurements are the two preponderant parameters. Our study aims at establishing the basis of reliable methods for archaeoastronomy.

Le score de propension : un guide méthodologique pour les recherches expérimentales et quasi expérimentales en éducation

2016

La méthode du score de propension devient de plus en plus populaire pour estimer les effets causaux d’un programme d’intervention. Si les applications empiriques de cette méthode sont encore rares dans les recherches en éducation, des exemples de son utilisation se trouvent aisément dans d’autres disciplines. Cependant, sa mise en place soulève plusieurs questions. L’objectif de cet article est de fournir des éléments de réponses guidant le chercheur et l’évaluateur du domaine de l’éducation pour l’estimation et l’utilisation du score de propension. Les différentes étapes de son application sont présentées pas à pas : évaluation du biais de sélection, construction du score de propension et …

Approche archéo-sociologique. Réseaux d'échanges

2012

A multivariate approach of the factors impacting a small arctic glacier, Austre Lovén-Spitsberg

2015

International audience; Arctic glaciers are good indicators of the ongoing climate change as their dynamics are strongly linked to it. This study is focused on the Austre Lovén glacier, on the Brøgger peninsula in Spitsbergen (Svalbard, 79°N). The aim is to understand how contrasted climate and snow conditions over the course of a year can lead to multiple consequences, sometimes unexpected, on mass balance. In 2014, a negative budget was expected, but data analysis has shown the first positive mass balance in 7 years. The objective here is to (i) identify and qualify the combination of factors affecting an arctic glacier mass balance. Three primary indicators seem to display the greatest i…

Évaluation de l'influence des facteurs climatiques sur le bilan de masse du glacier Austre Loven (Spitsberg, 79°N) par une approche multivariée

2016

Arctic is a region where a quick warming is ongoing. Effects are particularly visible on glaciers of which dynamics is very sensitive to climate change. The goal of this study is to identify and rank the main climatological and nivological factors influencing the mass balance of a small arctic glacier in Svalbard using a statistical approach. To highlight spatial differences, cartography were then used. Results show that positive degree-days play an important role in explaining mass balance contrary to liquid precipitations that had a marginal effect over the studied period (2007-2014). Moreover, years with very different climatic conditions can lead to a similar mass balance.