Results 31 to 40 of about 9,213,332 (293)

XMM-Newton study of the complex and variable spectrum of NGC 4051

, 2006
We study the X-ray spectral variability of the Narrow Line Seyfert 1 galaxy NGC 4051 as observed during two XMM-Newton observations. The data show evidence for a neutral and constant reflection component and for constant emission from photoionized gas ...
Cappi, M., Fabian, A. C., Iwasawa, K., Maraschi, L., Miniutti, G., Ponti, G.   +5 more
core   +3 more sources

Double Exponential Ratio Estimator of a Finite Population Variance under Extreme Values in Simple Random Sampling

Mathematics
This article presents an improved class of efficient estimators aimed at estimating the finite population variance of the study variable. These estimators are especially useful when we have information about the minimum/maximum values of the auxiliary ...
Umer Daraz, Jinbiao Wu, Olayan Albalawi
doaj   +1 more source

Improved class of estimators of finite population mean using sampling fraction and information on two auxiliary variables in sample surveys

Statistica, 2014
This paper suggested a generalized class of estimators using information on two auxiliary va-riables and sampling fraction in simple random sampling.
Housila P. Singh, Anjana Rathour, Ramkrishna S. Solanki   +2 more
doaj   +1 more source

A geoadditive Bayesian latent variable model for Poisson indicators [PDF]

, 2006
We introduce a new latent variable model with count variable indicators, where usual linear parametric effects of covariates, nonparametric effects of continuous covariates and spatial effects on the continuous latent variables are modelled through a ...
Fahrmeir, Ludwig, Steinert, Sven
core   +3 more sources

Optimizing Finite Population Mean Estimation Using Simulation and Empirical Data

Mathematics
Two-phase sampling is an effective sampling approach that is useful in sample surveys when prior auxiliary information is not available. When two variables have an association, the ranks of the auxiliary variable are proportional to the study variable ...
Abdulaziz S. Alghamdi, Fatimah A. Almulhim   +1 more
doaj   +1 more source

A Quality Improvement Initiative to Standardize Pneumocystis jirovecii Pneumonia Prophylaxis in Pediatric Patients With Solid Tumors

Pediatric Blood &Cancer, EarlyView.
ABSTRACT Background Pediatric patients with extracranial solid tumors (ST) receiving chemotherapy are at an increased risk for Pneumocystis jirovecii pneumonia (PJP). However, evidence guiding prophylaxis practices in this population is limited. A PJP‐related fatality at our institution highlighted inconsistent prescribing approaches and concerns about
Kriti Kumar, Denise M. Connolly, Ellen Kellington, Elyse Zelunka, Karla Kerrigan, Furqan Shaikh, Paul C. Nathan, Meredith S. Irwin, Sarah Cohen‐Gogo   +8 more
wiley   +1 more source

Enhanced estimation of population mean via exponential-type estimator using dual auxiliary inputs

Applied Mathematics in Science and Engineering
Without having to interview every person, we may draw conclusions about the whole population by estimating the population mean, a fundamental summary statistic that is obtained from a sample.
Poonam Singh, Pooja Maurya, Prayas Sharma   +2 more
doaj   +1 more source

A numerical study on impact and compression after impact behaviour of variable angle tow laminates [PDF]

, 2013
Recent developments of variable angled tow (VAT) technology have indicated that variable stiffness composite laminates offer a strong potential for structural tailoring.
Dang, Thi D., Hallett, Stephen R.
core   +2 more sources

Sickle Cell Disease Is an Inherent Risk for Asthma in a Sibling Comparison Study

Pediatric Blood &Cancer, EarlyView.
ABSTRACT Introduction Sickle cell disease (SCD) and asthma share a complex relationship. Although estimates vary, asthma prevalence in children with SCD is believed to be comparable to or higher than the general population. Determining whether SCD confers an increased risk for asthma remains challenging due to overlapping symptoms and the ...
Suhei C. Zuleta De Bernardis, Okeleji Olayinka, Mariam Z. Quraishi, Lakshmi V. Srivaths, Deborah L. Brown, Neethu M. Menon, Ricardo A. Mosquera, Ashwin P. Patel, James M. Stark, Aravind Yadav   +9 more
wiley   +1 more source

Evaluating methods for Lasso selective inference in biomedical research: a comparative simulation study

BMC Medical Research Methodology, 2022
Background Variable selection for regression models plays a key role in the analysis of biomedical data. However, inference after selection is not covered by classical statistical frequentist theory, which assumes a fixed set of covariates in the model ...
Michael Kammer, Daniela Dunkler, Stefan Michiels, Georg Heinze   +3 more
doaj   +1 more source