Search results for "Statistic"
showing 10 items of 12520 documents
Challenges in dental statistics: data and modelling
2022
The aim of this work is to present the reflections and proposals derived from the first Workshop of the SISMEC STATDENT working group on statistical methods and applications in dentistry, held in Ancona (Italy) on 28th September 2011. STATDENT began as a forum of comparison and discussion for statisticians working in the field of dental research in order to suggest new and improve existing biostatistical and clinical epidemiological methods. During the meeting, we dealt with very important topics of statistical methodology for the analysis of dental data, covering the analysis of hierarchically structured and over-dispersed data, the issue of calibration and reproducibility, as well as some…
Challenges in dental statistics: survey methodology topics
2022

 This paper gathers some contributions concerning survey methodology in dental research, as discussed during the first Workshop of the SISMEC STATDENT working group on statistical methods and applications in dentistry, held in Ancona on the 28th September 2011.
 The first contribution deals with the European Global Oral Health Indicators Development (EGOHID) Project which proposed a comprehensive and standardized system of epidemiological tools (questionnaires and clinical forms) for national data collection on oral health in Europe. The second contribution regards the design and conduct of trials to evaluate the clinical efficacy and safety of toothbrushes and mouthrinses. Final…
El afrontamiento del diagnóstico en pacientes y familiares oncológicos
2016
Introducción: La enfermedad oncológica produce un gran impacto emocional en nuestra población, no solo a los pacientes que las sufren sino a todo el entorno. Conocer el grado de afectación de la enfermedad tanto para los pacientes como a los familiares es primordial para el correcto cuidado por el personal sanitario. Pudiendo mejorar el afrontamiento de la enfermedad. Por tanto el presente estudio pretende conocer el grado de afectación del diagnóstico oncológico en pacientes como en familiares, así como conocer los aspectos que favorezcan el mismo.Metodología: Estudio descriptivo, observacional, transversal llevado a cabo en el Consorcio Hospitalario Provincial de Castellón, en 50 paciente…
A Preliminary Analysis of the Importance of Distance, Angle, and Insight When Soccer Referees Make Penalty Decisions
2021
Soccer referees move freely on the pitch to place themselves in the best location for making decisions. While Football Association UK (FA) highlights that a referee should never be more than 20 m away from the playing situation, previous studies have been inconsistent in indicating appropriate distance to a situation for increasing the likelihood of a correct decision. Further, appropriate angle and insight are also likely to influence the correctness of referees' decisions. The aim of this study was to provide an initial investigation of elite referees' positioning in the field (distance, angle, and insight) when making correct and erroneous decisions in potential penalty situations. An ex…
Why do female and male taekwondo athletes win the bout? An analysis based on the Olympic weight category and the result of the bout
2020
Combat sports such as taekwondo, where athletes compete against an opponent require control of technique and tactics, as well as knowing the optimal performance of opponents to win the bout. Therefore, the aim of the present study was to analyse the Olympic competitors (London Olympic Games), according to the weight category (fly, feather, light and heavy) and according to the performance in their fighting (winner vs. loser) in each gender. An observational methodology was used, following a nomothetic, follow-up and multidimensional design of 302 individual performances. The statistical analysis used an ANOVA and T Student test for comparing frequencies. The results obtained indicate signif…
The measurement invariance of Job Diagnostic Survey (JDS) across three university student groups
2016
Purpose: The main purpose of this study is to apply a multigroup confirmatory analysis to examine the measurement invariance (MI) of the adapted version of the Job Diagnosis Survey (JDS) as a measurement tool that analyses the relationship between the features of teaching methodologies with university students’ motivation and satisfaction across data collected on different degrees and academic years. Design/methodology/approach: Confirmatory factor analysis was carried out using a multigroup structural equation model, using the program EQS 6.1 to test the invariance of the adapted version of JDS in a sample constituted by 535 student of a Spanish public university. The assessment of invaria…
Determining the Number of Factors to Retain in EFA: An easy-to-use computer program for carrying out Parallel Analysis
2007
Parallel Analysis is a Monte Carlo simulation technique that aids researchers in determining the number of factors to retain in Principal Component and Exploratory Factor Analysis. This method provides a superior alternative to other techniques that are commonly used for the same purpose, such as the Scree test or the Kaiser's eigenvalue-greater-than-one rule. Nevertheless, Parallel Analysis is not well known among researchers, in part because it is not included as an analysis option in the most popular statistical packages. This paper describes and illustrates how to apply Parallel Analysis with an easy-to-use computer program called ViSta-PARAN. ViSta-PARAN is a user-friendly application …
Lead Excretion in Spanish Children with Autism Spectrum Disorder
2015
Among epigenetic factors leading to increased prevalence of juvenile neuropsychiatric disorders, including autism spectrum disorder, exposure to metals, such as lead (Pb) have led to conflicting results. The aim of the present study was to determine the levels of Pb in the urine of children with autism spectrum disorder (ASD) compared with typically developing children (TD) age- and sex-matched, and to analyze any association between core symptoms of ASD, special diets, supplements intake or prescription drugs and the concentration of Pb. The study was performed in a group of children with ASD (n = 35, average age 7.4 ± 0.5 years) and TD (n = 34, average age 7.7 ± 0.9 years). Measurement of…
Within-student variability in learning experiences, and teachers’ perceptions of students’ task-focus
2016
In order to advance models of educational processes (intraindividual, intensive longitudinal), we propose a model in which we specify state and trait constructs, and an intraindividual variability construct. In our ecological momentary assessment study, we investigated how trait-level and intraindividual variability of students’ learning experiences (intrinsic and extrinsic motivation, task difficulty, effort exertion, help-seeking and competence evaluations) converged with teacher-reported student task-focus. 285 primary school students’ (Years 5 and 6) completed the Learning Experience Questionnaire using handheld computers, on average 13.6 learning episodes during one week (SD = 4.6; Ran…
LASSO regression via smooth L1-norm approximation
2010
This paper discusses estimation of regression model with LASSO penalty when the L1-norm is replaced with its parametric smooth approximation. The resulting parameter estimators are more manageable than those from standard LASSO, standard errors are easy computed via a sandwich formula, and the model degrees of freedom may be computed straightforwardly. Moreover the resulting objective function may be minimized using usual optimization algorithms for regular models, for instance Newton-Raphson or iterative least squares.