Search results for "ECs"
showing 10 items of 2721 documents
Evaluating the effect of organization and context on technical efficiency: a second-stage DEA analysis of Italian hospitals
2022
Objective: the purpose of this study was to compare the technical efficiency of Italian hospitals at a regional level and to examine if differences could be explained by organisational and contextual factors. Technical efficiency was defined as the ability of the operating units evaluated to use optimal resource levels for their level of output.Methods: the effect of external factors was explored through a second stage Data Envelopment Analysis (DEA). Efficiency scores were calculated for each hospital using the DEA method (Stage I). Through Tobit regression analysis, the estimated efficiency scores were regressed against a set of organisational and contextual characteristics beyond manager…
A semi-parametric stochastic generator for bivariate extreme events
2017
The analysis of multiple extreme values aims to describe the stochastic behaviour of observations in the joint upper tail of a distribution function. For instance, being able to simulate multivariate extreme events is convenient for end users who need a large number of random replications of extremes as input of a given complex system to test its sensitivity. The simulation of multivariate extremes is often based on the assumption that the dependence structure, the so-called extremal dependence function, is described by a specific parametric model. We propose a simulation method for sampling bivariate extremes, under the assumption that the extremal dependence function is semiparametric. Th…
Six Sigma in small- and medium-sized enterprises: a Black Belt project in the Swedish steel industry
2014
Many big companies around the world have solid Six Sigma infrastructures and it is easy to find in literature successful case studies. Conversely, small and medium-sized enterprises (SMEs) generally suffer lower attention in the literature. This happens because SMEs have only recently approached the methodology; they have weaker connection with the academia; or they do not rigorously pursue the frameworks. This paper is based on a Six Sigma project in a Swedish medium-sized company that produces steel tubes mainly for hydraulic applications. The project focused on the improvement of warehouse activities related to cutting processes. This Black Belt project was part of a Six Sigma education …
Blockchain e criptovalute: strumento di democratizzazione imprenditoriale o bolla speculativa?
2018
L’obiettivo di questo lavoro (che costituisce il primo step di un più articolato percorso di ricerca) è di fornire un quadro teorico di riferimento utile alla comprensione delle possibili conseguenze che l’avvento della blockchain e delle criptovalute può avere sul contesto imprenditoriale e strategico-competitivo. Nello specifico, si vuole indagare se l’utilizzo della tecnologia blockchain possa rappresentare un effettivo strumento di “democratizzazione imprenditoriale” e di enfatizzazione del personal power dei singoli attori oppure sia il driver di una bolla speculativa basata sulle criptovalute.
The Complex System Theory for the Analysis of Inter-Firm Networks: A Literature Overview and Theoretic Framework
2011
In this paper we discuss the body of knowledge known as complex system theory and its relevance to the analysis of inter-firm networks. We start by addressing the development of systems thinking. Through a literature overview, we point out the main elements for the development of systemic thought from its beginning, through its application in business sciences, to the birth of Complex Systems Theory (CST). With these initial annotations we provide an introduction to the concepts of the complex systems theory. We will underscore those aspects of CST that can be useful to analyze inter-firm networks, in order to highlight the evolutionary dynamics of the networks and to clarify the logical li…
Book Review: Viable Systems Approach (VSA): Governing Business Dynamics
2015
This book introduces for the first time in English (and thus for an international readership) the Viable Systems Approach (VSA). The VSA is a novel systemic approach developed in Italy over a period of about thirty years by Italian systemic scholars under the guidance of Gaetano Golinelli.A strictly holistic view of systemic thinking puts the focus on the whole, as opposed to the parts. Accepting this view means directing all research efforts towards the understanding of the whole, without resorting to an analysis of the parts (Barile & Saviano, 2011). This perspective emerges in juxtaposition to the traditional analytical–reductionist approach, aiming to overcome its limits by moving towar…
Emergence of statistically validated financial intraday lead-lag relationships
2014
According to the leading models in modern finance, the presence of intraday lead-lag relationships between financial assets is negligible in efficient markets. With the advance of technology, however, markets have become more sophisticated. To determine whether this has resulted in an improved market efficiency, we investigate whether statistically significant lagged correlation relationships exist in financial markets. We introduce a numerical method to statistically validate links in correlation-based networks, and employ our method to study lagged correlation networks of equity returns in financial markets. Crucially, our statistical validation of lead-lag relationships accounts for mult…
Extropy: Complementary Dual of Entropy
2015
This article provides a completion to theories of information based on entropy, resolving a longstanding question in its axiomatization as proposed by Shannon and pursued by Jaynes. We show that Shannon's entropy function has a complementary dual function which we call "extropy." The entropy and the extropy of a binary distribution are identical. However, the measure bifurcates into a pair of distinct measures for any quantity that is not merely an event indicator. As with entropy, the maximum extropy distribution is also the uniform distribution, and both measures are invariant with respect to permutations of their mass functions. However, they behave quite differently in their assessments…