Poisson regression and negative binomial regression have been widely used to model the road crashes and to predict crash frequency. Zero inflated models have been shown to be a powerful tool to predict crash frequency when crash data are characterized by preponderance of zero. This paper presents the research work aiming to correlate the road traffic crash rate with road geometry and traffic ch...

BACKGROUND Traditional statistical models often are based on certain presuppositions and limitations that may not presence in actual data and lead to turbulence in estimation or prediction. In these situations, artificial neural networks (ANNs) could be suitable alternative rather than classical statistical methods. STUDY DESIGN  A prospective cohort study. METHODS The study was conducted i...

This paper describes the frequency and number of Sphyrion laevigatum in the skin of Genypterus blacodes, an important economic resource in Chile. The analysis of a spatial distribution model indicated that the parasites tended to cluster. Variations in the number of parasites per host could be described by a negative binomial distribution. The maximum number of parasites observed per host was two.

BACKGROUND Physical activity (PA) typically decreases with aging, especially of moderate to vigorous level, and this change affects health outcomes of older adults. Age-related decline is not evenly distributed across elderly population and is attributed to psychosocial, physical, and environmental determinants. METHODS We selected a sample of 1000 elderly people from urban parts of Shiraz in...

We show how the rootogram – a graphical tool associated with the work of J. W. Tukey and originally used for assessing goodness of fit of univariate distributions – can help to diagnose and treat issues such as overdispersion and/or excess zeros in regression models for count data. Two empirical illustrations, from ethology and from public health, are included. The former employs a negative bin...

Abstract In recent years, direct seeding as a means of stand establishment has experienced revival. Among other things it allows for an undisturbed root development and is assumed to be cost-efficient. While success factors have been worked out through numerous experiments, sound overviews failure in practice are scarce. With the goals (i) quantifying proportion (ii) extracting associated influ...

OBJECTIVE To evaluate recurrent neural networks as a predictive technique for time-series in the health field. METHODS The study was carried out during a cholera epidemic which took place in 1993 and 1994 in the state of Ceará, northeastern Brazil, and was based on excess deaths having 'poorly defined intestinal infections' as the underlying cause (ICD-9). The monthly number of deaths with du...