Search results for "ACCOUNTING"
showing 10 items of 1961 documents
On stability issues in deriving multivariable regression models
2014
In many areas of science where empirical data are analyzed, a task is often to identify important variables with influence on an outcome. Most often this is done by using a variable selection strategy in the context of a multivariable regression model. Using a study on ozone effects in children (n = 496, 24 covariates), we will discuss aspects relevant for deriving a suitable model. With an emphasis on model stability, we will explore and illustrate differences between predictive models and explanatory models, the key role of stopping criteria, and the value of bootstrap resampling (with and without replacement). Bootstrap resampling will be used to assess variable selection stability, to d…
Tests of Linearity, Multivariate Normality and the Adequacy of Linear Scores
1994
After some discussion of the purposes of testing multivariate normality, the paper concentrates on two different approaches to testing linearity: on repeated regression tests of non-linearity and on exploiting properties of a dichotomized normal distribution. Regression tests of linearity are used to examine the adequacy of linear scoring systems for explanatory variables, initially recorded on an ordinal scale. Examples from recent psychological and medical research are given in which the methods have led to some insight into subject-matter.
Distribucion final de referencia para el problema de Fieller-Creasy
1982
The problem of making inferences about the ratio of two normal populations is usually known as the Fieller-Creasy problem, and it gave rise to a controversy among fiducialists and confidence-intervalists. A Bayesian solution to such a problem when the two normal populations have the same unknown variance was presented by Bernardo (1977) using reference non-informative prior distributions. The solution to the case in which the variances are not assumed equal is obtained here. Some numerical results for artificial populations are given
Asymptotic efficiency of the calibration estimator in a high-dimensional data setting
2022
Abstract In a finite population sampling survey, auxiliary information is commonly used to improve the Horvitz-Thompson estimators and calibration has been extensively used by national statistical agencies over the last decades for that purpose. This method enables to make estimators consistent with known totals of auxiliary variables and to reduce variance if the calibration variables are explanatory for the variable of interest. Nowadays, it is not unusual anymore to have high-dimensional auxiliary data sets and adding too much additional calibration variables may increase the variance of calibration estimators. We study in this paper the asymptotic efficiency of the calibration estimator…
Efficient Estimation of Non-Linear Finite Population Parameters by Using Non-Parametrics
2013
Summary Currently, high precision estimation of non-linear parameters such as Gini indices, low income proportions or other measures of inequality is particularly crucial. We propose a general class of estimators for such parameters that take into account univariate auxiliary information assumed to be known for every unit in the population. Through a non-parametric model-assisted approach, we construct a unique system of survey weights that can be used to estimate any non-linear parameter that is associated with any study variable of the survey, using a plug-in principle. Based on a rigorous functional approach and a linearization principle, the asymptotic variance of the estimators propose…
GAMLSS for high-variability data: an application to liver fibrosis case
2020
In this paper, we propose management of the problem caused by overdispersed data by applying the generalized additive model for location, scale and shape framework (GAMLSS) as introduced by Rigby and Stasinopoulos (2005). The idea of using a GAMLSS approach for handling our problem comes from the idea of Aitkin (1996) consisting in the use of an EM maximum likelihood estimation algorithm (Dempster, Laird, and Rubin, 1977) to deal with overdispersed generalized linear models (GLM). As in the GLM case, the algorithm is initially derived as a form of Gaussian quadrature assuming a normal mixing distribution. The GAMLSS specification allows the extension of the Aitkin algorithm to probability d…
The Effects of Labor and Product Market Reforms: The Role of Macroeconomic Conditions and Policies
2018
The paper estimates the dynamic macroeconomic effects of labor and product market reforms on output, employment and productivity, and explores how these vary with prevailing macroeconomic conditions and policies. We apply a local projection method to a new dataset of major country- and country-sector-level reform shocks in various areas of labor market institutions and product market regulation covering 26 advanced economies over the past four decades. Product market reforms are found to raise productivity and output, but gains materialize only slowly. The impact of labor market reforms is primarily on employment, but it varies across types of reforms and depends on overall business cycle c…
Entstehen und Scheitern Strategischer Allianzen in der Telekommunikationsbranche
2001
Hungenberg (1998) has shown in this journal that strategic alliances have become an important strategic instrument in the telecommunications industry. Building up on this investigation we analyze the motives for the formation and failure of strategic alliances on the basis of a content analysis of the business newspaper “Handelsblatt” from 1995–1997. We show that in the telecommunications sector access to know-how and other resources as well as market access are the primary motives for the formation of strategic alliances. In contrast to other industries, cost and time advantages as motives are not relevant at all. The primary reason for the failure of strategic alliances was strategic reor…
A strategic needs perspective on operations outsourcing and other inter-firm relationships
2013
Abstract This paper considers two issues: the formation of inter-firm relationships, and the choice of governance form. These have been widely investigated in both the strategic management and operations management fields. This paper contributes to the literature in three ways. First, we address why firms enter inter-firm relationships by hypothesizing that managers enter them to pursue three strategic needs, that is: efficiency/effectiveness, knowledge/learning, and global market access. Our first contribution evidences the relationship between the above strategic needs and a number of operational objectives that managers normally pursue in an inter-firm relationship. Second, we hypothesiz…
Business agreements objectives and decisions: a field research
2013
PurposeMany research studies in operations management (OM) and strategic management (SM) investigate how different kinds of firm decisions regarding business relationships can positively affect a firm's operations performance, resource endowment, and competitive position. Very few studies exist, however, that have attempted to illuminate the actual behaviors of managers when making strategic decisions about their intercompany relationships; rather, most existing studies focus on normative theory. The purpose of this paper is to explore linkages between the “set” of strategic objectives that managers are willing to pursue, the “set” of networking decisions they make, and the “set” of busines…