Search results for "Statistic"

Analisi statistica delle serie temporali di dati provenienti dalla rete di stazioni permanenti dell’UNIPA

2010

In questo lavoro ci si è proposti di verificare la qualità dei dati provenienti dalle stazioni permanenti appartenenti alla rete dell’Università di Palermo, creata nell’ambito del progetto PRIN2005 dal titolo: “Reti di stazioni permanenti GPS per il rilievo in tempo reale in impieghi di controllo e emergenza” e gestita dal Dipartimento di Rappresentazione. Attualmente sono disponibili serie temporali di soluzioni giornaliere. Queste permettono di individuare fenomeni ed eventi di varia natura come quella geofisica, geologica, metereologica e, proprio in virtù della numerosità di questi dati si possono rilevare fenomeni di rumore più o meno complessi che possono essere apparentemente di natu…

Culture as an influence on sexting attitudes and behaviors: A differential analysis comparing adolescents from Spain and Colombia

2020

Abstract This study analyses the prevalence of sexting and the reasons and attitudes associated with its practice in adolescents with different cultural backgrounds (Colombia and Spain). The sample is made up of 489 Spaniards and 510 Colombians aged between 13 and 18 years. The results show that sexting is strongly influenced by gender and the country, in favor of men and Colombians respectively. The interaction between gender and country establishes that in Spain women and men practice sexting equally, while in Colombia men practice much more sexting than women. Although the practice of sexting increases progressively with age, the levels are higher among Colombian adolescents, especially …

Modeling of the Shear Connection Capacity of Hybrid Steel Trussed Composite Beams

2019

Hybrid Steel Trussed Composite Beams represent a technical solution in use in numerous countries since many years. They are able to join the advantages of prefabrication with those of cast in place structures: they are easy to manufacture, fast to realize, monolithic and with no need of formwork. The behavior of these beams has been recently topic of discussion in the scientific community because the knowledge both related to the reinforced concrete structures and that of composite constructions cannot be straightforwardly extended to this typology, which is intermediate between one and another technology. This paper provides a contribution towards a better understanding of the mechanism of…

ESTIMATING SOIL PARTICLE-SIZE DISTRIBUTION FOR SICILIAN SOILS

2009

The soil particle-size distribution (PSD) is commonly used for soil classification and for estimating soil behavior. An accurate mathematical representation of the PSD is required to estimate soil hydraulic properties and to compare texture measurements from different classification systems. The objective of this study was to evaluate the ability of the Haverkamp and Parlange (HP) and Fredlund et al. (F) PSD models to fit 243 measured PSDs from a wide range of 38 005_Bagarello(547)_33 18-11-2009 11:55 Pagina 38 soil textures in Sicily and to test the effect of the number of measured particle diameters on the fitting of the theoretical PSD. For each soil textural class, the best fitting perf…

Corrigendum: ExGUtils: A Python Package for Statistical Analysis With the ex-Gaussian Probability Density

2018

Testing and implementing a new approach to estimating interregional output multipliers using input-output data for South Korean regions

2020

Flegg's location quotient (FLQ) is a useful tool for estimating intraregional output multipliers. This paper uses it as one component when estimating interregional multipliers. Using statistical information criteria and official data for 16 South Korean regions, it is found that the best approach is to combine the FLQ with a simple trade model. The paper explains how the proposed procedure can be implemented for both multiple and individual regions, and also how a region-specific value for the unknown parameter δ in the FLQ formula can be determined. Finally, an illustrative case study of one of the regions is carried out.

Self-employment duration in urban and rural locations

2009

Previous research has shown that local environment is important for self-employment. Self-employment dynamics varies between areas characterized by different labour market conditions, entrepreneurial tradition and other structural factors. Alternation between different labour market states (self-employment, paid-employment, non-employment) is also likely to increase if employment opportunities remain low in local labour market markets. This paper analyses the factors influencing the duration of self-employment spells in Finland with a large registered-based data set from the period of 1987-2002. It is evident that rates of exit out of self-employment and the length of self-employment spells…

A Multi-Projector Calibration Method for Virtual Reality Simulators with Analytically Defined Screens

2017

The geometric calibration of projectors is a demanding task, particularly for the industry of virtual reality simulators. Different methods have been developed during the last decades to retrieve the intrinsic and extrinsic parameters of projectors, most of them being based on planar homographies and some requiring an extended calibration process. The aim of our research work is to design a fast and user-friendly method to provide multi-projector calibration on analytically defined screens, where a sample is shown for a virtual reality Formula 1 simulator that has a cylindrical screen. The proposed method results from the combination of surveying, photogrammetry and image processing approac…

Two‐sample problems in statistical data modelling

2010

A common problem in mathematical statistics is to check whether two samples differ from each other. From modelling point of view it is possible to make a statistical test for the equality of two means or alternatively two distribution functions. The second approach allows to represent the two‐sample test graphically. This can be done by adding simultaneous confidence bands to the probability‐probability (P — P) or quantile‐quantile (Q — Q) plots. In this paper we compare empirically the accuracy of the classical two‐sample t‐test, empirical likelihood method and several bootstrap methods. For a real data example both Q — Q and P — P plots with simultaneous confidence bands have been plotted…

Singular (p, q)-equations with superlinear reaction and concave boundary condition

2020

We consider a parametric nonlinear elliptic problem driven by the sum of a p-Laplacian and of a q-Laplacian (a (Formula presented.) -equation) with a singular and (Formula presented.) -superlinear reaction and a Robin boundary condition with (Formula presented.) -sublinear boundary term (Formula presented.). So, the problem has the combined effects of singular, concave and convex terms. We look for positive solutions and prove a bifurcation-type theorem describing the changes in the set of positive solutions as the parameter varies.