Search results for "Sample"
showing 10 items of 2270 documents
Determination of quality parameters of beers by the use of attenuated total reflectance-Fourier transform infrared spectroscopy
2005
Abstract The estimation of important quality parameters of beers, such as original and real extracts and alcohol content, has been evaluated by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) using a partial least square (PLS) calibration approach. Two sample populations, one consisting of 24 samples and other of 21 samples, obtained from the Spanish market and covering different types of beer were used. The first set was used for building and validating the model, whereas the second, measured 6 months after, was used for evaluating its robustness. The spectral range and the size of the calibration set and its suitability for building the PLS model have been …
Computing Sum of Products about the Mean with Pairwise Algorithms
1997
We discuss pairwise algorithms, a kind of computational algorithm which can be useful in dynamically updating statistics as new samples of data are collected. Since test data are usually collected through time as individual data sets, these algorithms would be profitably used in computer programs to treat this situation. Pair-wise algorithms are presented for calculating the sum of products of deviations about the mean for adding a sample of data (or removing one) to the whole data set.
Differences in Life Expectancy Between Self-Employed Workers and Paid Employees when Retirement Pensioners: Evidence from Spanish Social Security Rec…
2021
The aim of this paper is to examine differences in life expectancy (LE) between self-employed (SE) and paid employee (PE) workers when they become retirement pensioners, looking at levels of pension income using administrative data from Spanish social security records. We draw on the Continuous Sample of Working Lives (CSWL) to quantify changes in total life expectancy at age 65 (LE(65)) among retired men over the longest possible period covered by this data source: 2005–2018. These changes are broken down by pension regime and initial pension income level for three periods. The literature presents mixed evidence, even for the same country–for Japan and Italy, for example–with some studies …
The interaction between social media, knowledge management and service quality: A decision tree analysis
2020
The existing literature fails to identify to which extent the utilization of social media could be relevant for increasing the effectiveness of knowledge management, in respect to overall business operations. In order to shed some light on this area we define three goals. Firstly, we investigate to what extent the different activities of clients on social media (SM), are important to the processes of knowledge management (KM) in companies. Secondly, we examine to what extent KM functions can be relevant in attaining the quality of IT services. Thirdly, we analyze to what extent KM mediates between SM and the quality of IT services, that is, which client activities on SM should be formalised…
A ML Estimator of the Correlation Dimension for Left-hand Truncated Data Samples
2002
— A maximum-likelihood (ML) estimator of the correlation dimension d 2 of fractal sets of points not affected by the left-hand truncation of their inter-distances is defined. Such truncation might produce significant biases of the ML estimates of d 2 when the observed scale range of the phenomenon is very narrow, as often occurs in seismological studies. A second very simple algorithm based on the determination of the first two moments of the inter-distances distribution (SOM) is also proposed, itself not biased by the left-hand truncation effect. The asymptotic variance of the ML estimates is given. Statistical tests carried out on data samples with different sizes extracted from populatio…
Osseointegration of miniscrews: a histomorphometric evaluation.
2007
SUMMARY Mini-implants and miniscrews are commonly used in orthodontics to provide additional temporary intraoral anchorage. Partial osseointegration represents a distinct advantage in orthodontic applications, allowing effective anchorage to be combined with easy insertion and removal. This article reports the histomorphometric fi ndings of the osseointegration of bracket screw bone anchors (BSBAs). In an experimental animal study, four BSBAs were inserted in the alveolar process of the lower jaw in each of fi ve male beagle dogs, aged 6.5 months from the same mother. Eleven screws were lost during the study, nine of them due to lack of primary stability. One screw was removed at the end of…
Dependency in consumer media relations: an application to the case of teleshopping
2006
This paper analyses the teleshopping issue in terms of the Media Dependency Theory. The objective is to verify whether dependency relations between television shoppers and the television medium and television shopping are key variables to explain watching and buying behaviour. A model is proposed that integrates the dependency-viewing-purchase relation, tested on a sample of Spanish television shoppers. The results of the study confirm the direct relationship between the antecedents of dependency, dependency and future intentions of behaviour. Copyright © 2006 John Wiley & Sons, Ltd.
PERSONAL AND SITUATIONAL DETERMINANTS OF RELATIONSHIP-SPECIFIC PERCEPTIONS OF SOCIAL SUPPORT
2004
This study explores personal (self-esteem, perceived stress, and depressive mood) and situational (undesirable life events) variables as determinants of relationship-specific perceptions of social support. Structural equation analyses from two-wave panel data (N = 583) of adult participants from a community-based urban sample revealed that, after controlling for initial levels of perceived social support, psychological characteristics (high levels of stress and depression, and low levels of self-esteem) and situational determinants (number of undesirable life events) were both negatively related to perceived social support from specific significant relationships over time. Multigroup analys…
Familia, profesorado e iguales: claves para el apoyo a las víctimas de acoso escolar
2011
ResumenEl objetivo del presente estudio fue analizar las diferencias en ajuste psicológico en víctimas de acoso escolar en función de la calidad de sus relaciones con padres, profesores e iguales. En concreto, se compararon cuatro indicadores de ajuste psicológico (autoestima, ánimo depresivo, soledad y percepción de estrés) en víctimas con buena o mala comunicación con la madre, buena o mala comunicación con el padre, alta o baja percepción de ayuda del profesor, y alta o baja identificación con su grupo de iguales. La muestra inicial estuvo compuesta por 1795 adolescentes, entre 11 y 18 años (M=14.2, DT=1.68). Los resultados indicaron que las víctimas que mantenían mejores relaciones soci…
Assessing individual differences in driving inattention: Adaptation and validation of the Attention-Related Driving Errors Scale to Spain
2013
The Attention-Related Driving Errors Scale (ARDES) is a self-reported questionnaire to assess individual differences in the proneness to make attentional errors while driving. The aims of the current work are to adapt the original Argentinean version of the ARDES to the culture, language, traffic regulations and driving habits of Spain and provide new validity evidence of the cross-cultural equivalence of the scale. In the first step of the validation process, five external independent experts reviewed the original ARDES-Argentina and proposed modifications, adapted to the culture, language, traffic regulations and driving habits in Spain. Secondly, a sample of 320 drivers completed the ada…