Search results for "quantile regression."

Penalized regression and clustering in high-dimensional data

The main goal of this Thesis is to describe numerous statistical techniques that deal with high-dimensional genomic data. The Thesis begins with a review of the literature on penalized regression models, with particular attention to least absolute shrinkage and selection operator (LASSO) or L1-penalty methods. L1 logistic/multinomial regression models are used for variable selection and discriminant analysis with a binary/categorical response variable. The Thesis discusses and compares several methods that are commonly utilized in genetics, and introduces new strategies to select markers according to their informative content and to discriminate clusters by offering reduced panels for popul…

University student talent: the real driver for performance?

2017

Investigation about the university student performance, and its measurement, are very crucial issues for any policy maker. Since the economic crisis, jobs market requires even higher skills and competences. Literature offers a lot of papers about the university student quality and performance, in order to identify the main determinants of them. Often, results are very different, and they seems to hold just in a specific context. This paper aims to investigate the role of a latent variable that can take into account the student motivation, aptitude, and abilities, here conveniently called talent. A random effect Quantile Regression on a new measure of Italian student performance has been ado…

US stock market sensitivity to interest and inflation rates: a quantile regression approach

2016

ABSTRACTThis article studies the sensitivity of the US stock market to nominal and real interest rates and inflation during the 2003–2013 period using quantile regression (QR). The empirical results show that the stock market has a significant sensitivity to changes in interest rates and inflation and finds differences across sectors and over time. Moreover, the effect of changes in both interest rates and inflation tends to be more pronounced during extreme market conditions, thus distinguishing expansion periods from recession periods.

Inflation shocks and income inequality

2019

Purpose The purpose of this paper is to analyze the effects of inflationary shocks on inequality, using data of selected countries of the Middle East and North Africa (MENA). Design/methodology/approach Inflationary shocks were measured as deviations from core inflation, based on a genetic algorithm. Bayesian quantile regression was used to estimate the impact of inflationary shocks in different levels of inequality. Findings The results showed that inflationary shocks substantially affect countries with higher levels of inequality, thus suggesting that the detrimental impact of inflation is exacerbated by the high division of classes in a country. Originality/value The study contributes t…

Spatial mismatch through local public employment agencies Answers from a French quasi-experiment Spatial Mismatch through Local Public Employment Age…

2015

Using the unanticipated creation of a new agency in the French region of Lyon as a quasi-natural experiment, we question whether distance to local public employment agencies (LPEAs) is a new channel for spatial mismatch. Contrary to past evidence based on aggregated data and consistently with the spatial mismatch literature, we find no evidence of a worker/agency spatial mismatch, which pleads for a resizing of the French LPEA network. However, echoing with the literature on the institutional determinants of the local public employment agencies' efficiency, we do find detrimental institutional transitory effects.

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…

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…

Quantile Regression Coefficients Modeling: a Penalized Approach

2018

Modeling quantile regression coefficients functions permits describing the coefficients of a quantile regression model as parametric functions of the order of the quantile. This approach has numerous advantages over standard quantile regression, in which different quantiles are estimated one at the time: it facilitates estimation and inference, improves the interpretation of the results, and is statistically efficient. On the other hand, it poses new challenges in terms of model selection. We describe a penalized approach that can be used to identify a parsimonious model that can fit the data well. We describe the method, and analyze the dataset that motivated the present paper. The propose…

Productivity, Ownership & National Chains: Evidence from the British Retail Sector

2008

This paper investigates whether foreign-owned retailers operating in the British retail sector perform differently than domestic-owned firms with diverse national presence. Using simultaneous quantile regression techniques we test for any sign of performance gaps. The findings suggest that foreign ownership turns out to be a weak explanatory factor of differences in performance across retailers. Only when firms in the upper quantiles of TFP are compared, the role of foreign ownership gains statistical significance, although with exceptions. On the other hand, firms able to expand their infrastructure across Great Britain possess a productivity advantage over more local retailers. This impli…