Results 21 to 30 of about 21,802,969 (303)
Conditionally unbiased estimation in phase II/III clinical trials with early stopping for futility [PDF]
, 2013 Seamless phase II/III clinical trials combine traditional phases II and III into a single trial that is conducted in two stages, with stage 1 used to answer phase II objectives such as treatment selection and stage 2 used for the confirmatory analysis ...
Todd, Susan C. +6 more
core +1 more source
Two-Stage Channel Estimation for Semi-Passive RIS-Assisted Millimeter Wave Systems
Sensors, 2022 In a reconfigurable intelligent surface (RIS) assisted millimeter Wave (mmWave) communication system, the channel coefficient increases exponentially with the number of RIS elements which results in expensive pilot overhead.
Chengzuo Peng +5 more
doaj +1 more source
The Robust Variance Estimator for Two-stage Models [PDF]
The Stata Journal: Promoting communications on statistics and Stata, 2002 This article discusses estimates of variance for two-stage models. We present the sandwich estimate of variance as an alternative to the Murphy–Topel estimate. The sandwich estimator has a simple formula that is similar to the formula for the Murphy–Topel estimator, and the two estimators are asymptotically equal when the assumed model distributions ...
openaire +2 more sources
Estimation of Tropical Cyclone Intensity via Deep Learning Techniques from Satellite Cloud Images
Remote Sensing, 2023 Estimating the intensity of tropical cyclones (TCs) is usually involved as a critical step in studies on TC disaster warnings and prediction. Satellite cloud images (SCIs) are one of the most effective and preferable data sources for TC research. Despite
Biao Tong +5 more
doaj +1 more source
Millimeter-Wave Based Localization Using a Two-Stage Channel Estimation Relying on Few-Bit ADCs
IEEE Open Journal of the Communications Society, 2021 Benefiting from the high resolution in beamspace, millimeter wave (mmwave) communication has been regarded as a high-accuracy localization solution, where the location information is embedded in the channel via angle and time delay, for example.
Kunlun Li +2 more
doaj +1 more source
Two-stage re-estimation adaptive design: a simulation study
Epidemiology, Biostatistics and Public Health, 2022 Background: adaptive clinical trial design has been proposed as a promising new approach to improve the drug discovery process. Among the many options available, adaptive sample size re-estimation is of great interest mainly because of its ...
Francesca Galli, Luigi Mariani
doaj
Estimation in Two‐Stage Models with Heteroscedasticity
International Statistical Review, 2006 SummaryA surprising number of important problems can be cast in the framework of estimating a mean and variance using data arising from a two‐stage structure. The first stage is a random sampling of “units” with some quantity of interest associated with the unit.
openaire +3 more sources
Two-Stage Limited-Information Estimation for Structural Equation Models of Round-Robin Variables
StatsWe propose and demonstrate a new two-stage maximum likelihood estimator for parameters of a social relations structural equation model (SR-SEM) using estimated summary statistics (Σ^) as data, as well as uncertainty about Σ^ to obtain robust inferential ...
Terrence D. Jorgensen +2 more
doaj +1 more source
A Novel Two-Stage Illumination Estimation Framework for Expression Recognition
The Scientific World Journal, 2014 One of the critical issues for facial expression recognition is to eliminate the negative effect caused by variant poses and illuminations. In this paper a two-stage illumination estimation framework is proposed based on three-dimensional representative ...
Zheng Zhang, Guozhi Song, Jigang Wu
doaj +1 more source
Solid Pseudopapillary Neoplasm of the Pancreas in Children and Adolescents: Expert Recommendations
Pediatric Blood &Cancer, EarlyView.ABSTRACT Solid pseudopapillary neoplasm of the pancreas (SPN) is a rare low‐grade malignant exocrine pancreatic tumor, mostly discovered during the second decade of life in females, with a very good prognosis, provided microscopically complete surgical excision is achieved.
Sabine Irtan +18 more
wiley +1 more source