Search results for "Statistic"

GPU accelerated Monte Carlo simulations of lattice spin models

2011

We consider Monte Carlo simulations of classical spin models of statistical mechanics using the massively parallel architecture provided by graphics processing units (GPUs). We discuss simulations of models with discrete and continuous variables, and using an array of algorithms ranging from single-spin flip Metropolis updates over cluster algorithms to multicanonical and Wang-Landau techniques to judge the scope and limitations of GPU accelerated computation in this field. For most simulations discussed, we find significant speed-ups by two to three orders of magnitude as compared to single-threaded CPU implementations.

Computational cluster validation for microarray data analysis: experimental assessment of Clest, Consensus Clustering, Figure of Merit, Gap Statistic…

2008

Abstract Background Inferring cluster structure in microarray datasets is a fundamental task for the so-called -omic sciences. It is also a fundamental question in Statistics, Data Analysis and Classification, in particular with regard to the prediction of the number of clusters in a dataset, usually established via internal validation measures. Despite the wealth of internal measures available in the literature, new ones have been recently proposed, some of them specifically for microarray data. Results We consider five such measures: Clest, Consensus (Consensus Clustering), FOM (Figure of Merit), Gap (Gap Statistics) and ME (Model Explorer), in addition to the classic WCSS (Within Cluster…

A PARTITION TYPE METHOD FOR CLUSTERING MIXED DATA

1990

In this paper, we propose a method for clustering mixed data. The method is a nonhierarchical one, and deals simultaneously with variables of three main kinds: numerical, ordinal, and nominal. It is based on the minimization of a particular criterion f(G。) over all the partitions G。of n entities in m distinct clusters. The criterion is founded on a peculiar kind of internal standardized mean diversity of the entities, according to the three types of variables. The algorithm to get the best partition is also presented: it starts from a non-random choice of the first partition; the results are compared with those obtained by a random assignment to a first partition. In order to show the usefu…

Multivariate statistical analysis of heavy metals and physico-chemical parameters in the groundwater of Karak District, Khyber Pakhtunkhwa, Pakistan

2021

Groundwater heavy metal pollution is a major concern all around the world. For the assessment of heavy metals and physico-chemical characteristics. groundwater samples were collected from different locations of the Karak District, Pakistan. With the help of the global information system device (GIS), groundwater samples were collected and studied from 47 locations. The present study focused on the water table (WT), water source depth (WSD), pH, electrical conductivity (EC), dissolved oxygen (DO), total dissolved solids (TDS), lead (Pb(II)), silver (Ag(I)), iron (Fe(II)) and chromium (Cr(VI)) parameters. Heavy metals were analyzed by the Atomic Absorption Spectrophotometer (AAS). The Pearson…

Upper limits on the isotropic gravitational-wave background from Advanced LIGO and Advanced Virgo's third observing run

2021

We report results of a search for an isotropic gravitational-wave background (GWB) using data from Advanced LIGO's and Advanced Virgo's third observing run (O3) combined with upper limits from the earlier O1 and O2 runs. Unlike in previous observing runs in the advanced detector era, we include Virgo in the search for the GWB. The results are consistent with uncorrelated noise, and therefore we place upper limits on the strength of the GWB. We find that the dimensionless energy density $\Omega_{\rm GW}\leq 5.8\times 10^{-9}$ at the 95% credible level for a flat (frequency-independent) GWB, using a prior which is uniform in the log of the strength of the GWB, with 99% of the sensitivity comi…

Hating Adolescents Test (HAT): a preliminary development of a measure to assess hating among adolescents

2020

The phenomenon of haters is becoming common among adolescents. The aims of the present research were to evaluate the preliminary psychometric properties of the Hating Adolescents Test (HAT), an ad hoc questionnaire created to evaluate online and offline hate (Study 1), and possible risk factors connected with hate (Study 2). Participants (202 female and 200 male) of this study completed the HAT, the How I Think Questionnaire, the Buss–Perry Aggression Questionnaire, and the Penn State Worry Questionnaire. Descriptive statistics were calculated, and exploratory factor analysis and confirmatory factor analysis were applied. Preliminary data suggest how males reported higher level of hate than…

A Non-Local Mode-I Cohesive Model for Ascending Thoracic Aorta Dissections (ATAD)

2018

This paper presents a non-local interface mechanical model to describe aortic dissection. In this regard, the mode-I debonding problem based on a cohesive zone modeling is endowed with non-local terms to include long-range interactions that are present in multi-layered biological tissue. Such non-local effects are related to the collagen fibers that transmit forces between non-adjacent elements. Numerical simulations are provided with different values of the non-local parameters in order to show the effect of the non-locality during the debonding processes.

LA STATISTICA PER LA MISURA DELLA BELLEZZA

2018

Abstract · Statistics to measure beauty · We would like to point out an experimentation performed in an italian school in the first year of a Professional School in Palermo (Fashion course).A lot of ideas, such as beauty, proportionality, perfection can be found in many professional subjects and also in basic ones (Maths, Italian language, English language, Sciences, etc.). We tried to adapt M@t.abel (E-learning basic Maths) materials and methods “L’uomo di Vitruvio” (Bartolomei et al., 2010), to a professional school. This didactic activity, organized by the Maths teacher, involved other three teachers and lasted for 50 hours, not taking into account the planning and presentation to the cl…

Competitività e attrattività della destinazione. Definizioni operative e percorsi di misurazione.

2012

Linear ViscoElastic (LVE) Behaviour of Pure Bitumen via Fractional Model

2012

AbstractBy fitting experimental data from static creep/recovery carried out on pure bitumen, it is shown that the fractional model proposed enables the description of both creep and recovery behaviour with fewer parameters than those needed by other models in the literature. In particular, the model is fitted to experimental data of complex modulus |G*| and phase angle δ° obtained from Dynamic Mechanical Analysis. Lastly, it is demonstrated that when the fractional model is used, complex modulus isotherms for a range of frequencies can be created simply starting from isochronals at f = 1Hz.