Search results for "Statistic"
showing 10 items of 12520 documents
Il campionamento in campo turistico: le difficoltà di "fare" Statistica fra una malvasia e un'altra
2008
Externalizing Behaviors and Cigarette Smoking as Predictors for Use of Illicit Drugs: A Longitudinal Study Among Finnish Adolescent Twins
2010
We examined whether externalizing problem behaviors (hyperactivity–impulsivity, aggressiveness, and inattention) predict illicit drug use independently, or whether their associations with drug use are mediated through cigarette smoking. We used a prospective longitudinal design within theFinnTwin12-17study among Finnish adolescents with baseline at age 12 and follow-up surveys at ages 14 and 17. Path models were conducted withMplusand included 1992 boys and 2123 girls. The outcome was self-reported ever use of cannabis or other illicit drugs at age 17. The predictors were: externalizing behaviors (hyperactivity–impulsivity, aggressiveness, and inattention) assessed by teachers and parents (…
On the calculation of derived variables in the analysis of multivariate responses
1992
AbstractThe multivariate regression of a p × 1 vector Y of random variables on a q × 1 vector X of explanatory variables is considered. It is assumed that linear transformations of the components of Y can be the basis for useful interpretation whereas the components of X have strong individual identity. When p ≥ q a transformation is found to a new q × 1 vector of responses Y∗ such that in the multiple regression of, say, Y1∗ on X, only the coefficient of X1 is nonzero, i.e. such that Y1∗ is conditionally independent of X2, …, Xq, given X1. Some associated inferential procedures are sketched. An illustrative example is described in which the resulting transformation has aided interpretation.
Prevalence and factors associated with circadian blood pressure patterns in hypertensive patients.
2009
Comment in Timing of antihypertensive therapy and circadian blood pressure pattern. [Hypertension. 2009] Timing of antihypertensive therapy and circadian blood pressure pattern. Almirall J, Martínez-Ocaña JC, Comas L. Hypertension. 2009 Jun; 53(6):e41; author reply e42. Epub 2009 May 4. Dipping comes of age: the importance of nocturnal blood pressure. [Hypertension. 2009]. Dipping comes of age: the importance of nocturnal blood pressure. O'Brien E. Hypertension. 2009 Mar; 53(3):446-7. Epub 2009 Jan 26.Nondipping in patients with hypertension. [Hypertension. 2009] Ambulatory blood pressure (BP) monitoring has become useful in the diagnosis and management of hypertensive individuals. In addit…
Caries Severity, Decayed First Permanent Molars and Associated Factors in 6-7 Years Old Schoolchildren Living in Palermo (Southern Italy).
2023
To date, there are very few epidemiologic studies on caries disease in 6–7 year old children living in Sicily (Southern Italy). The first permanent molar (FPM) is the most commonly affected tooth in this target population, and a one-unit increase in the number of decayed FPMs is predictive of caries in other teeth and in adulthood. The primary aim of this research is to estimate the prevalence of caries in 6–7 year old schoolchildren living in Palermo and, as a secondary aim, to estimate the prevalence of affected FPMs. It was designed as a cluster cross-sectional survey on 995 children from 16 schools, selected based on their geographical location, in one of the eight city districts. Carie…
Reliability and Validity of The Finnish Version of The Boston Carpal Tunnel Questionnaire among Surgically Treated Carpal Tunnel Syndrome Patients
2019
Background and Aims: The Boston Carpal Tunnel Questionnaire is the most commonly used outcome measure in the assessment of carpal tunnel syndrome. The purpose of this study was to translate the original Boston Carpal Tunnel Questionnaire into Finnish and validate its psychometric properties. Materials and Methods: We translated and culturally adapted the Boston Carpal Tunnel Questionnaire into Finnish. Subsequently, 193 patients completed the Finnish version of the Boston Carpal Tunnel Questionnaire, 6-Item CTS Symptoms Scale, and EuroQol 5 Dimensions 12 months after carpal tunnel release. The Boston Carpal Tunnel Questionnaire was re-administered after a 2-week interval. We calculated cons…
Chi rimane e chi se ne va? Un’analisi statistica della mobilità universitaria dal Mezzogiorno d’Italia
2020
Nel 1999, il “Processo di Bologna” ha proposto la realizzazione dello spazio europeo di istruzione superiore (concretizzatosi nell’European Higher Education Area - EHEA) con l’intento di promuovere la conoscenza, la mobilità e la coesione culturale fra i paesi europei e il resto del mondo. Tali obiettivi sono stati ribaditi nel Comunicato di Bucarest (2012), approvato dai Ministri dell’Istruzione Superiore dei 47 membri dell’EHEA, in cui si mette l’accento sulla necessità di garantire, da un lato, il massimo livello possibile di finanziamento pubblico per l’istruzione superiore, come forma di investimento per il superamento della crisi finanziaria e, da un altro lato, un accesso paritario a…
Empirical analysis of daily cash flow time-series and its implications for forecasting
2019
Usual assumptions on the statistical properties of daily net cash flows include normality, absence of correlation and stationarity. We provide a comprehensive study based on a real-world cash flow data set showing that: (i) the usual assumption of normality, absence of correlation and stationarity hardly appear; (ii) non-linearity is often relevant for forecasting; and (iii) typical data transformations have little impact on linearity and normality. This evidence may lead to consider a more data-driven approach such as time-series forecasting in an attempt to provide cash managers with expert systems in cash management.
Does self-efficacy influence academic results? A separable-effect mediation analysis
2021
In causal mediation analysis, natural effects are identified only under strict assumptions involving cross-world counterfactuals. An alternative approach recently developed, called separable, allows for identification of mediational effects in a wide range of models, since it relies on weaker assumptions than those required by natural effects. In this paper, the separable-effect approach is revised and an application to data is presented.
Information Decomposition in Bivariate Systems: Theory and Application to Cardiorespiratory Dynamics
2015
In the framework of information dynamics, the temporal evolution of coupled systems can be studied by decomposing the predictive information about an assigned target system into amounts quantifying the information stored inside the system and the information transferred to it. While information storage and transfer are computed through the known self-entropy (SE) and transfer entropy (TE), an alternative decomposition evidences the so-called cross entropy (CE) and conditional SE (cSE), quantifying the cross information and internal information of the target system, respectively. This study presents a thorough evaluation of SE, TE, CE and cSE as quantities related to the causal statistical s…