Results 71 to 80 of about 7,731 (299)

Two Kantorovich-type inequalities and efficiency comparisons between the OLSE and BLUE

Journal of Inequalities and Applications, 2002
We first establish two matrix-determinant Kantorovich-type inequalities. Then we introduce two efficiency criteria and make efficiency comparisons between the ordinary least squares estimator and best linear unbiased estimator in linear models.
King Maxwell L, Liu Shuangzhe
doaj  

Remote Assessment of Ataxia Severity in SCA3 Across Multiple Centers and Time Points

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective Spinocerebellar ataxia type 3 (SCA3) is a genetically defined ataxia. The Scale for Assessment and Rating of Ataxia (SARA) is a clinician‐reported outcome that measures ataxia severity at a single time point. In its standard application, SARA fails to capture short‐term fluctuations, limiting its sensitivity in trials.
Marcus Grobe‐Einsler, Vivian Maas, Arian Taheri Amin, Jennifer Faber, Tamara Schaprian, Katharina Hill, Matthis Synofzik, Lisa H. Graf, Heike Jacobi, Manuela Lima, Ana F. Ferreira, Bart P. van de Warrenburg, Ilse H. J. Willemse, Dagmar Timmann, Andreas Thieme, Paola Giunti, Hector Garcia‐Moreno, Magda M. Santana, Jeannette Hübener‐Schmid, Elin H. Davies, Thomas Klockgether   +20 more
wiley   +1 more source

Comparing ols and rank-based estimation techniques for production analysis: An application to Ghanaian maize farms.

Apstract: Applied Studies in Agribusiness and Commerce, 2016
This paper introduces the rank-based estimation method to modelling the Cobb-Douglas production function as an alternative to the least squares approach.
Henry De-Graft Acquah
doaj   +1 more source

Consistent least squares fitting of ellipsoids

, 2004
A parameter estimation problem for ellipsoid fitting in the presence of measurement errors is considered. The ordinary least squares estimator is inconsistent, and due to the nonlinearity of the model, the orthogonal regression estimator is inconsistent ...
Van Huffel, S., Kukush, A., Markovsky, I.   +2 more
core  

Resurrecting weighted least squares [PDF]

, 2016
This paper shows how asymptotically valid inference in regression models based on the weighted least squares (WLS) estimator can be obtained even when the model for reweighting the data is misspecified.
Romano, Joseph P., Wolf, Michael; https://orcid.org/, Wolf, Michael, Michael Wolf, Romano, Joseph P, Joseph P. Romano   +5 more
core   +1 more source

Five‐Year Disease Progression in Synuclein Seeding Positive Sporadic Parkinson's Disease

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective To provide a comprehensive description of disease progression in synuclein seeding assay (SAA) positive sporadic Parkinson Disease participants, using Neuronal Synuclein Disease integrated biological and functional impairment staging framework.
Paulina Gonzalez‐Latapi, Caroline Gochanour, Seung Ho Choi, Hyunkeun Cho, Chelsea Caspell‐Garcia, Christopher Coffey, Michael Brumm, David‐Erick Lafontant, Yuge Xiao, Thomas Tropea, John Seibyl, Caroline Tanner, Charles S. Venuto, Karl Kieburtz, Lana M. Chahine, Kathleen L. Poston, Andrew Siderowf, Kenneth Marek, Tanya Simuni, The Parkinson's Progression Markers Initiative   +19 more
wiley   +1 more source

The Comparison Between Different Approaches to Overcome the Multicollinearity Problem in Linear Regression Models

Ibn Al-Haitham Journal for Pure and Applied Sciences, 2018
    In the presence of multi-collinearity problem, the parameter estimation method based on the ordinary least squares procedure is unsatisfactory. In 1970, Hoerl and Kennard insert analternative method labeled as estimator of ridge regression.
Hazim Mansoor Gorgees, Fatimah Assim Mahdi   +1 more
doaj   +1 more source

Maximum Score Type Estimators [PDF]

This paper presents maximum score type estimators for linear, binomial, tobit and truncated regression models. These estimators estimate the normalized vector of slopes and do not provide the estimator of intercept, although it may appear in the model ...
Marcin Owczarczuk
core  

Value of MRI Outcomes for Preventive and Early‐Stage Trials in Spinocerebellar Ataxias 1 and 3

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective To examine the value of MRI outcomes as endpoints for preventive and early‐stage trials of two polyglutamine spinocerebellar ataxias (SCAs). Methods A cohort of 100 participants (23 SCA1, 63 SCA3, median Scale for the Assessment and Rating of Ataxia (SARA) score = 5, 42% preataxic, and 14 gene‐negative controls) was scanned at 3T up ...
Thiago J. R. Rezende, Emilien Petit, Young Woo Park, Sophie Tezenas du Montcel, James M. Joers, Jonathan M. DuBois, H. Moore Arnold, Michal Povazan, Ipek Özdemir, Guita Banan, Romain Valabregue, Philipp Ehses, Jennifer Faber, Chiadi U. Onyike, Peter B. Barker, Jeremy D. Schmahmann, Eva‐Maria Ratai, Sub H. Subramony, Thomas H. Mareci, Khalaf O. Bushara, Henry Paulson, Thomas Klockgether, Alexandra Durr, Tetsuo Ashizawa, Christophe Lenglet, Gülin Öz, READISCA Investigators   +26 more
wiley   +1 more source

Performance Evaluation of Measures of Central Tendency (MCT) in Tackling Missing Data in Collinear Regressors: A Comparison of Linear Estimators [PDF]

The Egyptian Statistical Journal
The presence of missing data and multicollinearity in regression analysis poses significant challenges to the reliability and accuracy of model estimates.
Abass Taiwo, Oluwatobi Ogunnusi, Timothy Olatayo, Biodun Efuwape   +3 more
doaj   +1 more source