Search results for "value"
showing 10 items of 5321 documents
A computational proposal for a robust estimation of the Pareto tail index: An application to emerging markets
2022
Abstract In this work, we backtest and compare, under the VaR risk measure, the fitting performances of three classes of density distributions (Gaussian, Stable and Pareto) with respect to three different types of emerging markets: Egypt, Qatar and Mexico. We also propose a new technique for the estimation of the Pareto tail index by means of the Threshold Accepting (TAVaR) and the Hybrid Particle Swarm Optimization algorithm (H-PSOVaR). Furthermore, we test the accuracy and robustness of our estimates demonstrating the effectiveness of the proposed approach.
Missing Value Estimation for Microarray Data by Bayesian Principal Component Analysis and Iterative Local Least Squares
2013
Published version of an article from the journal: Mathematical Problems in Engineering. Also available from Hindawi: http://dx.doi.org/10.1155/2013/162938 Missing values are prevalent in microarray data, they course negative influence on downstream microarray analyses, and thus they should be estimated from known values. We propose a BPCA-iLLS method, which is an integration of two commonly used missing value estimation methods-Bayesian principal component analysis (BPCA) and local least squares (LLS). The inferior row-average procedure in LLS is replaced with BPCA, and the least squares method is put into an iterative framework. Comparative result shows that the proposed method has obtaine…
Corruption, political discretion and entrepreneurship
2018
Purpose While common sense suggests that corruption will likely have a negative impact on the economy as it raises the cost of doing business, research on the topic showed inconsistent results (positive, negative and neutral). This paper aims to verify whether corruption has a “grease” or “sand” effect on the wheels of entrepreneurial rates and under which conditions corruption will have stronger or weaker effects. Design/methodology/approach Using institutional theory as the basis for the hypotheses, generalized least squares estimation is conducted to empirically examine the role of corruption and political discretion in entrepreneurship in a sample of 93 countries. Findings Countries wi…
Alcohol boosts pheromone production in male flies and makes them sexier
2020
The attraction of Drosophila melanogaster towards byproducts of alcoholic fermentation, especially ethanol, has been extensively studied 1–4. However, the adaptive value of this behavior has not been elucidated. Previous studies have suggested anthropomorphic interpretations of D. melanogaster behavior towards alcohols 5,6. Here, we instead assert that there exists a simple yet vital biological rationale for alcohol contact and consumption by these insects. We show that exposure to alcohols, especially methanol, results in an immediate amplification of fatty acid ester pheromone levels, which in turn elevates the probability that a male will successfully compete for a female during courtshi…
Indicadores de calidad para analizar la información televisiva sobre grupos minoritarios. El caso de “El ángel rubio”
2015
Este estudio propone una evaluación de la calidad periodística utilizando indicadores interculturales y códigos deontológicos. Para ello se observa la cobertura televisiva internacional, ofrecida por las televisiones públicas europeas BBC, TF 2 France, RAI 1 y TVE 1 en el período del 19 al 22 de octubre de 2013, de la historia conocida mediáticamente como “el ángel rubio”: la aparición de una niña en un campamento gitano en Grecia, en un presunto caso de tráfico de menores o de un secuestro. Se constata que la información se aleja de los estándares de calidad y contribuye a la estigmatización de los gitanos y a la etnificación del delito.
Diving into the uncertainties of open innovation: A systematic review of risks to uncover pertinent typologies and unexplored horizons
2023
The open innovation paradigm has created substantial new opportunities for firms in various sectors. However, scholars have long expressed concern that open innovation also entails a dark side, which can result in value co-destruction. This concern highlights the importance of devoting attention to the perils of pursuing open innovation. Existing scholarship has given due credence to these perils by examining various associated risks and uncertainties. We observe that the extant literature is siloed and unorganized, which impedes future research. Positing that an endeavor to organize existing studies may enhance the pace of research in the area, we attempt to address this gap by reviewing t…
A study on spectral optimisation in partial response CPM signals
1995
An optimisation technique for the minimisation of the effective bandwidth in partial response CPM signals is described. The minimum Euclidean distance is used as optimisation constraint because the bit error probability is a function of this parameter for high values of signal to noise ratio. The procedure has been implemented for a correlation length corresponding to two signalling intervals. The optimisation problem leads to a system of two nonlinear differential equations for the pulse shape, together with some boundary conditions. Numerical solution of the differential equations has been performed; initial conditions have been adjusted, to satisfy the boundary conditions using an iterat…
Data Mining Algorithms for Knowledge Extraction
2020
In this paper, we study the methods, techniques, and algorithms used in data mining, and from the studied algorithms, we emphasized the clustering algorithms, more precisely on the K-means algorithm. This algorithm was first studied using the Euclidean distance, then modifying the distance between the clusters using the distances Mahalanobis and Canberra. After implementing the algorithms in C/C++, we compared the clustering of the three algorithms, after which we modified them and studied the distance between the clusters.
Corporate spin-offs value creation : parent & spin-off view
2015
Corporate spin-offs have gained popularity over the past few years. Despite of this in Finnish media and university teaching this phenomenon has gained little attention. This study aims to fulfill this knowledge gap. Spin-off is a restructuring procedure where company splits into two separate legal entities via pro-rata transaction basis. I researched this phenomenon by event-study methodology which has been quite popular also in earlier studies. I have com-pared parent and spin-off stock performance in order to reveal potential value gains for investors. Parent company is analyzed also from the announcement period where we find strong positive abnormal returns associated with announcement …
Hacia un modelo de neuro-responsabilidad: una perspectiva de la responsabilidad social desde el desarrollo humano
2011
The rise of neuroscience's study, based on the technological development that allows to investigate brain processes by neuroimaging, has led to a new research area which after the neuro prefix covers studies such as neuroeconomics, neuromarketing and social neuroscience . This paper provides a review based on different research projects with the aim of presenting social responsibility, often conceptually linked to organizational paradigms, as an evolutionary trend of neurological human development, which could be called Neuro-responsibility El auge del estudio desde la neurociencia, con base en el desarrollo tecnológico que permite investigar los procesos cerebrales mediante la neuro-imágen…