Search results for "STATISTICS"
showing 10 items of 7671 documents
A new sample of large angular size radio galaxies
2004
We present in this paper a detailed study of a new sample of large angular size FR I and FR II radio galaxies and compare the properties of the two classes. As expected, a pure morphology based distinction of FR Is and FR IIs corresponds to a break in total radio power. The radio cores in FR Is are also weaker than in FR IIs, although there is not a well defined break power. We find that asymmetry in the structure of the sample members must be the consequence of anisotropies in the medium where the lobes expand, with orientation playing a minor role. Moreover, literature data and our observations at kiloparsec scales suggest that the large differences between the structures of FR I and FR I…
Older people’s participation in political organizations: The role of generativity and its impact on well-being
2017
Aging population has increased a global concern to keep seniors active and healthy. Civic participation, in particular, has been highlighted for its social and community benefits and its impact on elders’ health and well-being. To date, however, most studies have explored volunteering; other types of civic activities, such as political participation, are largely overlooked. This study analyzes the relationship between older people’s active involvement in political organizations, generativity, and hedonic and eudaimonic well-being. We selected two samples of Spanish older people: a sample of elders actively involved in political organizations (n = 97) and a comparison group (n = 85). Measure…
Análisis de la distancia recorrida en pádel en función del nivel de juego y el número de puntos por partido (Analysis of distance covered in padel ba…
2020
La distancia que recorren los jugadores por partido supone una forma de cuantificar el volumen de carga externa del juego, y su estudio tiene una gran aplicación en la planificación del entrenamiento deportivo. El objetivo de este estudio fue analizar la distancia recorrida en diferentes fases del partido (activa y pasiva) y su relación con el número de puntos disputados y nivel de juego de los deportistas. La muestra estuvo compuesta por 108 jugadores federados de pádel (edad media = 33.81 ± 6.72 años). Se analizaron, a través de observación sistemática con el sistema SAGIT, un total 4406 puntos correspondientes a 27 partidos de pádel. Los partidos fueron divididos en tres niveles de compe…
Mobile Phone Data Statistics as Proxy Indicator for Regional Economic Activity Assessment
2019
The mobile data analysis is an authoritative source of information for problems solving in the fields of human activity recognition, population dynamics, tourism, transport planning, traffics measuring, public administration and other activities and could be the source for valuable information as a proxy indicator. One of the obstacles to user data from mobile operators is compliance to the General Data Protection Regulation, so the development of data analytics approach that protects personal data without a necessity to identify mobility of particular persons was developed, that still provides economically relevant data. In the present research, the method for the economic activity assessm…
Daily evapotranspiration assessment by means of residual surface energy balance modeling: A critical analysis under a wide range of water availability
2012
Summary An operational use of the actual evapotranspiration assessed by remote sensing approaches requires the integration of instantaneous fluxes to daily values. This is commonly achieved under the hypotheses of daytime self-preservation of evaporative fraction and negligible daily ground heat flux. The aim of this study is to evaluate the effect of these assumptions on estimate daily evapotranspiration over a full phenological cycle, including phases characterized by significant changes both in net radiation and vegetation cover. To assess the reliability of these hypotheses, the observations made by a flux tower, installed within a homogeneous field of cereal located in the valley part …
The Separating Role of Collateral Requirements in Credit Markets with Asymmetric Information
2001
In this paper we test Bester's (1985, 1987) prediction about the separating role of contracts that involve both interest rates and collateral requirements in credit markets. To test this prediction we use data from natural credit markets and controlled experiments. Using a sample of credits to small and medium size firms in Valencia, Spain, we relate two different types of contracts with the ex post risk type of the borrower and other relevant variables. We then design two incentive compatible contracts and analyze decisions under two different experimental treatments, one with moral hazard. Our empirical results confirm that borrowers of ex post lower risk choose contracts with higher coll…
A fuzzy ranking strategy for portfolio selection applied to the Spanish stock market
2007
In this paper we present a fuzzy ranking procedure for the portfolio selection problem. The uncertainty on the returns of each portfolio is approximated by means of a trapezoidal fuzzy number. The expected return and risk of the portfolio are then characteristics of that fuzzy number. A rank index that accounts for both expected return and risk is defined, allowing the decision-maker to compare different portfolios. The paper ends with an application of that fuzzy ranking strategy to the Spanish stock market.
Initial Enlargement in a Markov chain market model
2011
Enlargement of filtrations is a classical topic in the general theory of stochastic processes. This theory has been applied to stochastic finance in order to analyze models with insider information. In this paper we study initial enlargement in a Markov chain market model, introduced by Norberg. In the enlarged filtration, several things can happen: some of the jumps times can be accessible or predictable, but in the original filtration all the jumps times are totally inaccessible. But even if the jumps times change to accessible or predictable, the insider does not necessarily have arbitrage possibilities.
Combining Benford's Law and machine learning to detect money laundering. An actual Spanish court case.
2017
Abstract Objectives This paper is based on the analysis of the database of operations from a macro-case on money laundering orchestrated between a core company and a group of its suppliers, 26 of which had already been identified by the police as fraudulent companies. In the face of a well-founded suspicion that more companies have perpetrated criminal acts and in order to make better use of what are very limited police resources, we aim to construct a tool to detect money laundering criminals. Methods We combine Benford’s Law and machine learning algorithms (logistic regression, decision trees, neural networks, and random forests) to find patterns of money laundering criminals in the conte…
Personal Gains from Materials in Social Networks
2021
Importance of gains from social networks is analyzed in great extent in many countries by many researchers as social networks are reaching more and more importance. Research methods applied: analysis of scientific publications, survey of social network users on gains from materials in social networks. For evaluations by respondents in survey it was used evaluation scale 1–6 as it is used in grading system in Germany. Survey data results are analyzed by indicators of descriptive statistics – indicators of central tendency or location: arithmetic mean, median, mode and indicator of variability – standard deviation. In the research there were found differences by countries in use of social net…