Search results for "regression"
showing 10 items of 2619 documents
Geographical spread of influenza incidence in Spain during the 2009 A(H1N1) pandemic wave and the two succeeding influenza seasons
2014
SUMMARYThe aim of this study was to monitor the spatio-temporal spread of influenza incidence in Spain during the 2009 pandemic and the following two influenza seasons 2010–2011 and 2011–2012 using a Bayesian Poisson mixed regression model; and implement this model of geographical analysis in the Spanish Influenza Surveillance System to obtain maps of influenza incidence for every week. In the pandemic wave the maps showed influenza activity spreading from west to east. The 2010–2011 influenza epidemic wave plotted a north-west/south-east pattern of spread. During the 2011–2012 season the spread of influenza was geographically heterogeneous. The most important source of variability in the m…
Is diversity of leisure-time sport activities associated with low back and neck–shoulder region pain? A Finnish twin cohort study
2019
This study investigates cross-sectional and longitudinal associations between the diversity of leisure-time sport activities and the frequencies of low back pain (LBP) and neck-shoulder region pain (NSP) in twins, including a cross-sectional within-pair design to adjust for potential familial confounding. Finnish twins born in 1975–79 (FinnTwin16 study) reported participation in leisure-time sport activities at the mean ages of 17 (1992–96) (n = 5096, 54% females) and 34 years (2010−12) (n = 3731, 57% females). Diversity assessed as the number of sport activities was categorized as 1, 2, 3, 4, and ≥ 5, excluding inactive individuals. The frequencies of LBP (n = 3201) and NSP (n = 3207), rep…
Modelling Inoculum Availability ofPlurivorosphaerella nawaein Persimmon Leaf Litter with Bayesian Beta Regression
2019
AbstractCircular leaf spot (CLS), caused byPlurivorosphaerella nawae, is a serious disease of persimmon (Diospyros kaki) inducing necrotic lesions on leaves, defoliation and fruit drop. Under Mediter-ranean conditions,P. nawaeforms pseudothecia in the leaf litter during winter and ascospores are released in spring infecting susceptible leaves. Persimmon growers are advised to apply fungicides for CLS control during the period of inoculum availability, which was defined based on ascospore counts under the microscope. A model of inoculum availability ofP. nawaewas developed and evaluated as an alternative to ascospore counts. Leaf litter samples were collected weekly in L’Alcúdia from 2010 to…
Transfers of care between healthcare professionals in obstetric units of different sizes across spain and in a hospital in Ireland: The midconbirth s…
2020
Background: In Europe, the majority of healthy women give birth at conventional obstetric units with the assistance of registered midwives. This study examines the relationships between the intrapartum transfer of care (TOC) from midwife to obstetrician-led maternity care, obstetric unit size (OUS) with different degrees of midwifery autonomy, intrapartum interventions and birth outcomes. Methods: A prospective, multicentre, cross-sectional study promoted by the COST Action IS1405 was carried out at eight public hospitals in Spain and Ireland between 2016&ndash
Population density and childhood leukaemia: results of the EUROCLUS study
1999
The EUROCLUS study assembled incidence data for 13,551 cases of childhood leukaemia (CL) diagnosed between 1980 and 1989 in 17 countries (or regions of countries). These were referenced by location at diagnosis to small census areas of which there were 25,723 in the study area. Population counts, surface area and, hence, population density were available for all these small areas. Previous analyses have shown limited extra-Poisson variation (EPV) of case counts within small areas; this is most pronounced in areas of intermediate population density (150-499 persons/km2). In this study, the data set was examined in more detail for evidence that variations in incidence and EPV of CL are associ…
Markers of Anemia in Children with Type 1 Diabetes
2018
Aim. The aim of the study was to assess markers of anemia in type 1 diabetes (T1D) children, compare them to results obtained in the control group, and estimate their relation to BMI SDS. Methods. 94 (59% ♀) T1D children without other autoimmune disorders, aged 12.5 ± 4.1 years, T1D duration: 4.2 ± 3.6 years, HbA1c 7.3 ± 1.5% (57 ± 12.6 mmol/mol). Sex- and age-matched controls (43 children). In all children, anthropometric measurements, the blood count, iron turnover parameters, and vitamin B12 concentration were taken. Results. T1DM children had significantly higher red cell distribution width (RDW) (13.6 versus 12.6%; p<0.001), hepcidin (0.25 versus 0.12 ng/ml; p<0.001), and vitamin…
Penalization and data reduction of auxiliary variables in survey sampling
2012
Survey sampling techniques are quite useful in a way to estimate population parameterssuch as the population total when the large dimensional auxiliary data setis available. This thesis deals with the estimation of population total in presenceof ill-conditioned large data set.In the first chapter, we give some basic definitions that will be used in thelater chapters. The Horvitz-Thompson estimator is defined as an estimator whichdoes not use auxiliary variables. Along with, calibration technique is defined toincorporate the auxiliary variables for sake of improvement in the estimation ofpopulation totals for a fixed sample size.The second chapter is a part of a review article about ridge re…
Estimation de la relation de salaires de Mincer : choix de specification et enjeux économétriques
2012
In the present doctoral thesis, we estimated Mincer’s (1974) semi logarithmic wage function for the French and Pakistani labour force data. This model is considered as a standard tool in order to estimate the relationship between earnings/wages and different contributory factors. Despite of its vide and extensive use, simple estimation of the Mincerian model is biased because of different econometric problems. The main sources of bias noted in the literature are endogeneity of schooling, measurement error, and sample selectivity. We have tackled the endogeneity and measurement error biases via instrumental variables two stage least squares approach for which we have proposed two new instrum…
Estimation of National Colorectal-Cancer Incidence Using Claims Databases
2012
Background.The aim of the study was to assess the accuracy of the colorectal-cancer incidence estimated from administrative data.Methods.We selected potential incident colorectal-cancer cases in 2004-2005 French administrative data, using two alternative algorithms. The first was based only on diagnostic and procedure codes, whereas the second considered the past history of the patient. Results of both methods were assessed against two corresponding local cancer registries, acting as “gold standards.” We then constructed a multivariable regression model to estimate the corrected total number of incident colorectal-cancer cases from the whole national administrative database.Results.The firs…
Network-Constrained Covariate Coefficient and Connection Sign Estimation
2020
Often, variables are linked to each other via a network. When such a network structure is known, this knowledge can be incorporated into regularized regression settings via a network penalty term. However, when the type of interaction via the network is unknown (that is, whether connections are of an activating or a repressing type), the connection signs have to be estimated simultaneously with the covariate coefficients. This can be done with an algorithm iterating a connection sign estimation step and a covariate coefficient estimation step. We develop such an algorithm and show detailed simulation results and an application forecasting event times. The algorithm performs well in a variet…