Search results for "regres"
showing 10 items of 2935 documents
A series expansion of the extended Debye-H�ckel equation and application to linear prediction of stability constants
1996
The Debye-Hückel semiempirical extended equation is frequently used to calculate activity coefficients of chemical species and equilibrium constants at ionic strengths different from those used in their experimental evaluation. A series expansion of the extended Debye-Hückel equation is proposed here and checked with experimental data taken from the literature. The expansion is linear in the ionic parameters and yields a geometrical series which converges rapidly and that enables the accurate calculation of interpolated and extrapolated activity coefficients and equilibrium constants by simple and multiple linear regression without previous knowledge of the ionic parameters.
Transpiration and Water Use of an Irrigated Traditional Olive Grove with Sap-Flow Observations and the FAO56 Dual Crop Coefficient Approach
2021
The SIMDualKc model was applied to evaluate the crop water use and the crop coefficient (Kc) of an irrigated olive grove (Olea europaea L.) located in Sicily, Italy, using experimental data collected from two crop seasons. The model applies the FAO56 dual Kc approach to compute the actual crop evapotranspiration (ETc act) and its components, i.e., the actual tree transpiration (Tc act), obtained through the basal crop coefficient (Kcb), and soil evaporation according to an evaporation coefficient (Ke). Model calibration was performed by minimizing the difference between the predicted Tc act and the observed daily tree transpiration measured with sap flow instrumentation (TSF field) acquired…
Linear and nonlinear interest rate exposure in Spain
2010
PurposeThis paper aims to carry out a comprehensive analysis of the influence of interest rate risk on Spanish firms at the industry level.Design/methodology/approachThe methodology employed has its origin in the two‐index linear regression model proposed by Stone. This traditional interest rate exposure model has been extended in this paper to allow for a nonlinear exposure component as well as the presence of asymmetric behaviour in the exposure pattern.FindingsInterest rate exposure is not homogeneous for all the Spanish industries. In line with other markets, highly leveraged industries (construction and real estate), regulated industries (electrical and utilities), and banking industry…
Participation in organized sports is associated with decreased likelihood of unhealthy lifestyle habits in adolescents
2018
Adolescence is a pivotal time for investing in both present and future health. Thus, it is important to identify arenas for promoting positive adolescent health behaviors and preventing negative ones. The aim of this study was to investigate the associations between organized sports participation (OSP) and a broad range of lifestyle habits in Norwegian adolescents. A comprehensive survey was completed by 13 269 junior high and high school students in southern Norway. Multivariable binary logistic regression models, adjusted for gender, age, and parental education, were used to investigate the associations between OSP and adolescent substance use, dietary habits, physical activity level, pas…
Prediction of embryo survival and live birth rates after cryotransfers of vitrified blastocysts
2020
Which pre-vitrification parameters are the most predictive of survival and live birth in vitrified-warmed blastocyst transfer cycles?A retrospective study including 11,936 warmed blastocysts. Pre-vitrification morphological parameters analysed for blastocysts included day of vitrification; blastocyst expansion degree; trophoectoderm grade (A, B and C); and inner cell mass grade (A, B and C). Univariate and multivariate generalized estimating equations models were used to analyse survival, clinical pregnancy and live birth rate. A stepwise regression analysis was conducted to select and classify by order which outcomes were the most predictive.The odds of survival increased almost twice for …
Outcomes for adults with anorexia nervosa who do not respond early to outpatient treatment
2021
Objective: To better understand those patients with anorexia nervosa who do not show early response to treatment and are likely to have poorer outcome. Method: From an existing data set of 187 patients with anorexia nervosa across 22 eating disorder outpatient services in the United Kingdom, participants who had started treatment and had at least one body mass index (BMI) observation in the first 6 weeks of treatment were eligible for these secondary analyses (N = 65), a latent class analysis of BMI change over the first 6 weeks of treatment. Fifty-six patients showed no early change in BMI. We used logistic regression to examine predictors of good outcome in the 40 participants who had 12-…
Can We Define the Risk of Lymph Node Metastasis in Early-Stage Cervical Cancer Patients? A Large-Scale, Retrospective Study
2017
BACKGROUND: Sentinel lymph node (SLN) biopsy has emerged as one of the most appreciated techniques for reducing the rate of complete lymph node dissection (LND) performed in patients with early-stage cervical cancer (ECC). However, its performances are still a matter of debate and, to improve them, international guidelines recommend performing at least unilateral LND in case of SLN mapping. In a prior study, we identified a group of patients without evidence of lymph node metastasis (LNM). Our objective is to define a precise risk of LNM for each ECC patient in order to significantly tailor surgery for ECC. METHODS: Clinical and pathological data of ECC patients were retrospectively collect…
Socio-demographic characteristics are related to the advanced clinical stage of oral cancer
2019
Background Social determinants may be associated with the onset and progression of the clinical stage of oral cancer. Aim: To evaluate the impact of socio-demographic characteristics on the prevalence of advanced clinical stage of oral cancer. Material and Methods Information about 51,116 cases of oral cancer, from all Brazilian states, between 2000 and 2012, was obtained from the Cancer Registry Information System. The clinical stage of oral cancer (dependent variable) was classified as initial (stages I and II) or advanced (stages III and IV). The relationship between the clinical stage of oral cancer and the following independent variables was analyzed: sex, age, schooling, marital statu…
Dosage individualization of erythropoietin using a profile-dependent support vector regression
2003
The external administration of recombinant human erythropoietin is the chosen treatment for those patients with secondary anemia due to chronic renal failure in periodic hemodialysis. The objective of this paper is to carry out an individualized prediction of the EPO dosage to be administered to those patients. The high cost of this medication, its side-effects and the phenomenon of potential resistance which some individuals suffer all justify the need for a model which is capable of optimizing dosage individualization. A group of 110 patients and several patient factors were used to develop the models. The support vector regressor (SVR) is benchmarked with the classical multilayer percept…
Normal values of M mode echocardiographic measurements of more than 2000 healthy infants and children in central Europe
2000
OBJECTIVE—To obtain normal M mode (one dimensional) echocardiographic values in a substantial sample of normal infants and children. DESIGN—Data were obtained over three years from a single centre in central Europe. PATIENTS—2036 healthy infants and children aged one day to 18 years. METHODS—In line with recommendations for standardising measurements from M mode echocardiograms, and using digital echocardiographic equipment, measurements were obtained of the following: right ventricular anterior wall thickness at end diastole, right ventricular end diastolic dimension, thickness of interventricular septum at end diastole and end systole, thickness of posterior wall of the left ventricle at …