Search results for "Statistical"

showing 10 items of 4960 documents

The Dimensions of Facebook Addiction as Measured by Facebook Addiction Italian Questionnaire and Their Relationships with Individual Differences

2017

Abstract The studies reported analyze the factorial structure of Facebook Addiction Italian Questionnaire (FAIQ), a variant of 20-item Young's Internet Addiction Test (IAT). In Study 1, we tested FAIQ psychometric properties using exploratory factor analysis (EFA). In Study 2, we performed a confirmatory factor analysis (CFA) to verify the FAIQ factorial structure identified through EFA. Results from CFA confirm the presence of a four-factor model accounting for 58 percent of total variance, plus a general higher order factor that best fits the data. Further relationships between FAIQ factor scores, personality, and Facebook usage have been explored.

Settore M-PSI/01 - Psicologia GeneraleAdultMaleFacebookInternet addictionAdolescentPsychometricsSocial Psychologymedia_common.quotation_subjectIndividuality050801 communication & media studies050109 social psychologyYoung Adult0508 media and communicationsInternet addiction testSurveys and QuestionnairesHumansPersonalityTranslations0501 psychology and cognitive sciencesComputingMilieux_MISCELLANEOUSApplied PsychologyAgedmedia_commonAged 80 and overSettore INF/01 - Informaticasocial networkingCommunicationAddiction05 social sciencesGeneral MedicineMiddle AgedExploratory factor analysisConfirmatory factor analysisComputer Science ApplicationsBehavior AddictiveHuman-Computer InteractionItaly[SCCO.PSYC]Cognitive science/PsychologyFemaleFactor Analysis StatisticalPsychologySocial MediaPersonalityClinical psychologyCyberpsychology, Behavior, and Social Networking
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Sequentially Forecasting Economic Indices Using Mixture Linear Combinations of EP Distributions

2021

This article displays an application of the statistical method moti- vated by Bruno de Finetti's operational subjective theory of probability. We use exchangeable forecasting distributions based on mixtures of linear com- binations of exponential power (EP) distributions to forecast the sequence of daily rates of return from the Dow-Jones index of stock prices over a 20 year period. The operational subjective statistical method for comparing distributions is quite different from that commonly used in data analysis, because it rejects the basic tenets underlying the practice of hypothesis test- ing. In its place, proper scoring rules for forecast distributions are used to assess the values o…

Settore MAT/06 - Probabilita' E Statistica MatematicaLogarithmDow-Jones index exponential power distributions fat tails logarithmic scoring rule mixture distributions partial exchangeability proper scoring rules subjective probability subjectivist statistical methods.Scoring ruleStatistical parameterExponential functionNormal distributionSettore SECS-S/06 -Metodi Mat. dell'Economia e d. Scienze Attuariali e Finanz.StatisticsEconometricsSettore SECS-S/01 - StatisticaLinear combinationMathematicsStatistical hypothesis testingJournal of Data Science
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Diffusion modeling of COVID-19 under lockdown

2021

Viral immune evasion by sequence variation is a significant barrier to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine design and coronavirus disease-2019 diffusion under lockdown are unpredictable with subsequent waves. Our group has developed a computational model rooted in physics to address this challenge, aiming to predict the fitness landscape of SARS-CoV-2 diffusion using a variant of the bidimensional Ising model (2DIMV) connected seasonally. The 2DIMV works in a closed system composed of limited interaction subjects and conditioned by only temperature changes. Markov chain Monte Carlo method shows that an increase in temperature implicates reduced virus diffusi…

Settore MED/17 - Malattie InfettiveCoronavirus disease 2019 (COVID-19)Fitness landscapeSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2)virusesComputational Mechanicsmedicine.disease_cause01 natural sciencesSettore MED/01 - Statistica Medica010305 fluids & plasmassymbols.namesakeARTICLES0103 physical sciencesmedicineStatistical physicsDiffusion (business)010306 general physicsCoronavirusFluid Flow and Transfer ProcessesPhysicsDiffusion modelingBiofluid MechanicsMechanical EngineeringMarkov chain Monte CarloCondensed Matter PhysicsDiffusion modeling COVI 19Mechanics of MaterialssymbolsIsing modelPhysics of Fluids
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Scritti in onore di Pellegrino Capaldo

2014

La qualità dei servizi è stata riconosciuta come un rilevante aspetto caratterizzante la performance dell’azienda pubblica, analogamente alla capacità di operare secondo criteri di efficienza e nel rispetto dei vincoli di bilancio. Sebbene sia possibile riscontrare alcuni significativi casi di adozione di politiche di customer satisfaction nelle amministrazioni pubbliche italiane, a tutt’oggi il tema presenta significative criticità, specialmente in ordine agli aspetti metodologici e agli strumenti operativi che consentano di integrare dette politiche nel sistema di programmazione e controllo delle aziende che erogano tali servizi. Il presente lavoro adotta una diversa prospettiva di analis…

Settore SECS-P/07 - Economia AziendaleQuality in delivering public services has been recognised as a major issue challenging performance in the public sector as well as the ability to operate effectively and within budget constraints. Empirical findings shown by the literature demonstrate that concrete efforts have been produced towards the evaluation and improvement of satisfaction levels of citizens and other Public Administration’s ‘customers’. However still today this issue portrays many unresolved criticalities particularly concerning the methodological approaches and operative tools to adopt in order to integrate ‘customer satisfaction’ programs with the wider organisational control system in each public administration. This paper adopts a non-conventional view of the ‘customer satisfaction’ concept. This is currently meant as a matter of social reporting or even statistical analysis based on the users’ perceptions on the level of provided services by a given (front office) unit in the public sector. Here an inter-institutional perspective is adopted with a view to map the overall value chain leading to the final product delivered to citizens or the community. Inside this chain tracking the underlying administrative products delivered by back-office units to their ‘internal clients’ in the public administration is recommended as a fundamental step to understand how to improve performance in satisfying citizens’ needs. This should also require a proper link between the administrative units’ goals and performance measures to the desired efficiency and effectiveness of processes leading to the attainment of administrative products providing the basis of the final services delivered to the private sector. Based on first empirical findings from field analysis in the Italian context the paper aims to outline an approach which could assist both politicians and managers to better assess and improve performance according to a customer satisfaction perspective.
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A Proposal to estimate the roaming–dog Total in an urban area through a PPSWOR spatial sampling with sample size greater than two

2018

Settore SECS-S/05 - Statistica SocialeDogs roaming in urban areas constitute an issue for public order hygiene and health. Proper planning of actions for health and security control and allocation of financial funds require the knowledge of the roaming–dog–population size in a given urban area. Unfortunately a reliable statistical procedure aimed to measure such population is not available yet in literature. This paper presents a simple reproducible survey sampling procedure to estimate the number of roaming dogs in an urban area through the description of a real study carried out on a restricted area of the city of Palermo in southern Italy. A sample of areas is drawn by means of a drawn–by–drawn spatial sampling with probabilities proportional to size and without replacement (PPSWOR). As inclusion probabilities are not available in closed form they are estimated by Monte Carlo approach which is of simple implementation and permits design–based variance estimation even when first–order inclusion probabilities are unknown.
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Statistically Validated Networks for assessing topic quality in LDA models

2022

Probabilistic topic models have become one of the most widespread machine learning technique for textual analysis purpose. In this framework, Latent Dirichlet Allocation (LDA) (Blei et al., 2003) gained more and more popularity as a text modelling technique. The idea is that documents are represented as random mixtures over latent topics, where a distribution overwords characterizes each topic. Unfortunately, topic models do not guarantee the interpretability of their outputs. The topics learned from the model may be only characterized by a set of irrelevant or unchained words, being useless for the interpretation. Although many topic-quality metrics were proposed (Newman et al., 2009; Alet…

Settore SECS-S/06 -Metodi Mat. dell'Economia e d. Scienze Attuariali e Finanz.Settore SECS-S/01 - StatisticaTopic Model Topic Coherence LDA Statistically Validated Networks
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Statistically Validated Networks for evaluating coherence in topic models

2022

Probabilistic topic models have become one of the most widespread machine learning technique for textual analysis purpose. In this framework, Latent Dirichlet Allocation (LDA) gained more and more popularity as a text modelling technique. The idea is that documents are represented as random mixtures over latent topics, where a distribution over words characterizes each topic. Unfortunately, topic models do not guarantee the interpretability of their outputs. The topics learned from the model may be characterized by a set of irrelevant or unchained words, being useless for the interpretation. In the framework of topic quality evaluation, the pairwise semantic cohesion among the top-N most pr…

Settore SECS-S/06 -Metodi Mat. dell'Economia e d. Scienze Attuariali e Finanz.Text Mining Probabilistic Topic Models Topic coherence Statistically Validated NetworksSettore SECS-S/01 - Statistica
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MEASURING TOPIC COHERENCE THROUGH STATISTICALLY VALIDATED NETWORKS

2020

Topic models arise from the need of understanding and exploring large text document collections and predicting their underlying structure. Latent Dirichlet Allocation (LDA) (Blei et al., 2003) has quickly become one of the most popular text modelling techniques. The idea is that documents are represented as random mixtures over latent topics, where a distribution over words characterizes each topic. Unfortunately, topic models give no guaranty on the interpretability of their outputs. The topics learned from texts may be characterized by a set of irrelevant or unchained words. Therefore, topic models require validation of the coherence of estimated topics. However, the automatic evaluation …

Settore SECS-S/06 -Metodi Mat. dell'Economia e d. Scienze Attuariali e Finanz.topic model topic coherence LDA statistically validated networks.Settore SECS-S/01 - Statistica
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STRANIERI, MERIDIONALI O PROVINCIALI? I CONSUMI NEL TEMPO LIBERO DELLE SECONDE GENERAZIONI

2022

In this paper, we analyze consumption patterns of leisure time among young people belonging to the so-called “second generation” of immigrants in Italy. Leisure time consumption describes how young immigrants use cultural products and services. We analyze data collected by the ISTAT through the survey on the “second generations” (2015). A comparison of leisure consumption patterns between second-generation immigrants and their Italian peers does not show significant differences. Rather, differences in consumption styles are associated to gender (male/female), geographic area of residence (North/South), and size of the municipality (large municipality/small municipality) of residence.

Settore SPS/07 - Sociologia GeneraleYoung immigrants Leisure time consumption Social integration Statistically validated networks.
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<p>Clinical Phenotype and Response to Different Lines of Therapy in Elderly with Immune Thrombocytopenia: A Retrospective Study</p>

2020

Purpose Insufficient knowledge of primary immune thrombocytopenia purpura (ITP) in the elderly, together with a lack of clinical trial data, has resulted in wide variation in treatments. Here, we present a study focused on clinical characteristics of ITP in older subjects at diagnosis integrated with the subsequent course of the disease and treatment history. Methods In a retrospective monoinstitutional study, we evaluated >65-year-old patients with primary ITP. Clinical characteristics at the time of diagnosis were described and analyzed. We aimed to delineate whether subsequent lines of therapy influenced the number of relapses. In addition to initial regimens, we reported subsequent trea…

Severe bleedingmedicine.medical_specialtybusiness.industryRetrospective cohort studyHematologyDisease030204 cardiovascular system & hematologyImmune thrombocytopeniaClinical trial03 medical and health sciencesPurpura0302 clinical medicine030220 oncology & carcinogenesisStatistical significanceInternal medicineMedicinemedicine.symptombusinessClinical phenotypeJournal of Blood Medicine
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