نتایج جستجو برای: systematic error random error epid
تعداد نتایج: 790237 فیلتر نتایج به سال:
In this paper we first show that standard BP algorithm cannot yeild to a uniform information distribution over the neural network architecture. A measure of sensitivity is defined to evaluate fault tolerance of neural network and then we show that the sensitivity of a link is closely related to the amount of information passes through it. Based on this assumption, we prove that the distribu...
Classical variational data assimilation methods address the problem of optimally combining model predictions with observations in the presence of zero-mean Gaussian random errors. However, in many natural systems, uncertainty in model structure and/or model parameters often results in systematic errors or biases. Prior knowledge about such systematic model error for parametric removal is not al...
The present study is aimed at determination of accuracy of relocation of Gill-Thomas-Cosman frame during fractionated stereotactic radiotherapy. The study aims to quantitatively determine the magnitudes of error in anteroposterior, mediolateral and craniocaudal directions, and determine the margin between clinical target volume to planning target volume based on systematic and random errors. Da...
PURPOSE To describe an MR imaging quantification method for estimation of total volumes of both white and gray matter subcortical lesions and ventricular cerebrospinal fluid (CSF) in the living human brain, and to determine the method's reliability. METHODS In 12 subjects, total subcortical lesion and ventricular CSF volumes were estimated using systematic sampling. Systematic sampling was pe...
The systematic errors that are induced by a combination of human memory limitations and common survey design and implementation have long been studied in the context of egocentric networks. Despite this, little if any work exists in the area of random error analysis on these same networks; this paper offers a perspective on the effects of random errors on egonet analysis, as well as the effects...
With the increased use of data not originally recorded for research, such as routine care data (or 'big data'), measurement error is bound to become an increasingly relevant problem in medical research. A common view among medical researchers on the influence of random measurement error (i.e. classical measurement error) is that its presence leads to some degree of systematic underestimation of...
This paper considers the issue of document type diversity in the Comparative Manifestos Project (CMP). For many years the CMP has been collecting and coding a variety of documents, such as speeches, pamphlets, newspaper articles and leaflets, as manifesto proxies. By using previously unexplored archival material to perform controlled comparisons between different types of documents, this paper ...
OBJECTIVE To measure setup error of head and neck neoplasm in radiotherapy and discuss over effects of error on physical dose acting on target region and organs at risk of nasopharynx cancer (NPC) patients treated with intensity modulated radiation therapy (IMRT). METHODS A total of 152 patients who developed head and neck neoplasm and received IMRT were randomly selected. Through comparing d...
Background and Objectives: HBV DNA monitoring is important in management of chronic viral hepatitis B infection. HBV DNA measurements are carried out over period of months to years. So the analytical system must be stable and reproducible. The aim of this study was to determine the performance characteristics and to plan a statistical quality control system of a laboratory-developed real-tim...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید