Results 101 to 110 of about 5,006 (131)

Tests Conditional on Imbalance with Biased Coin Designs.

1986
Abstract : Distributional properties of the treatment assignment variables T sub 1, ..., T sub n under Efron's (1971) biased coin design are derived. These properties are conditional on the terminal imbalance of the treatment allocation. Recursive procedures are presented for obtaining the conditional moments of T sub 1, ..., T sub n.
Edsel Pena, Myles Hollander
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Doubly adaptive biased coin designs with heterogeneous responses

Journal of Statistical Planning and Inference, 2009
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Duan, Liangliang, Hu, Feifang
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Adaptive biased-coin designs for clinical trials with several treatments

Discussiones Mathematicae Probability and Statistics, 2023
Summary: Adaptive designs are used in phase III clinical trials for skewing the allocation pattern towards the better treatments. We use optimum design theory to provide a skewed biased-coin procedure for sequential designs with continuous responses.
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An optimal response adaptive biased coin design with k heteroscedastic treatments

Journal of Statistical Planning and Inference, 2011
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Gwise, Thomas E., Zhou, Jianhui, Hu, Feifang   +2 more
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Balance and randomness in sequential clinical trials: the dominant biased coin design

Pharmaceutical Statistics, 2014
AbstractEfron's biased coin design (BCD) is a well‐known randomization technique that helps neutralize selection bias, while keeping the experiment fairly balanced for every sample size. Several extensions of this rule have been proposed, and their properties were analyzed from an asymptotic viewpoint and compared via simulations in a finite setup. The
BALDI ANTOGNINI, ALESSANDRO, ZAGORAIOU, MAROUSSA   +1 more
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Dose Finding Using the Biased Coin Up‐and‐Down Design and Isotonic Regression

Biometrics, 2002
Summary.We are interested in finding a dose that has a prespecified toxicity rate in the target population. In this article, we investigate five estimators of the target dose to be used with the up‐and‐down biased coin design (BCD) Introduced By Durham and Flournoy (1994,Statistical Decision Theory and Related Topics).These estimators are derived using
Stylianou, Mario, Flournoy, Nancy
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Covariate-adjusted inference for doubly adaptive biased coin design

Statistical Methods in Medical Research
Randomized controlled trials (RCTs) are pivotal for evaluating the efficacy of medical treatments and interventions, serving as a cornerstone in clinical research. In addition to randomization, achieving balances among multiple targets, such as statistical validity, efficiency, and ethical considerations, is also a central issue in RCTs.
Fuyi Tu, Wei Ma
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Asymptotic Properties of Biased Coin Designs for Treatment Allocation

2004
Biased coin designs (BCD) are a special type of randomized sequential experiments. A common feature of several BCD’s is their Markov property, which allows a direct study of the design asymptotics. Possible criteria for comparing different biased coin designs are discussed with reference to particular cases.
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On inferences from Wei's biased coin design for clinical trials

Biometrika, 1990
Wei (1988) analyzed data from a clinical trial in which an urn-sampling model was used to allocate patients to treatments. The trial resulted in 11 patients being allocated to the experimental treatment, all successes, and with one patient allocated to the control treatment, a failure.
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An adaptive biased coin design for the behrens-fisher problem

Sequential Analysis, 1990
Wei(1978) introduced the adaptive biased coin design to reduce experimenter bias and offer a compromise between perfect balance and complete randomization. In situations such as the Behrens-Fisher problem, balance is not necessarily desired and the optimal ratio of sample sizes is unknown.
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