Results 291 to 300 of about 142,506 (314)

Restricted stratified random sampling

International Journal of Mineral Processing, 1989
Abstract A method of sampling is described which is a compromise between systematic sampling and stratified random sampling. It has less potential for bias than systematic sampling and also avoids the practical problems associated with stratified random sampling.
Geoffrey K. Robinson, Geoffrey K. Robinson, Ian W. Saunders, Ian W. Saunders   +3 more
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Significance tests with restricted randomization design

Biometrika, 1983
In an experiment comparing the effectiveness of two treatments, A and B, subjects arrive at an experimental site sequentially and must be assigned immediately to one of the two treatment groups. The complete randomization scheme, tossing a fair coin each time independently to decide which treatment will be used for the next subject, has been widely ...
R. T. Smythe, L. J. Wei
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Restricted Randomization: A Practical Example

Journal of the American Statistical Association, 1987
Abstract A method of restricted randomization, which avoids bad patterns in the treatments but retains validity in the analysis, is demonstrated on an example that exhibits many features of real agricultural experiments, such as untidy treatment structure and uncertainty about blocking. The method uses permutation groups.
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Use and reporting of restricted randomization: a review

Journal of Evaluation in Clinical Practice, 2015
AbstractRationale, aims and objectivesRestricted randomization, such as blocking or minimization, allows for the creation of balanced groups and even distribution of covariates, but it increases the risk of selection bias and technical error. Various methods are available to reduce these risks but there is limited evidence about their current usage ...
Yvonne Birks, Puvan Tharmanathan, Ruchi Higham   +2 more
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Restricted random walks on graphs

Theoretica Chimica Acta, 1995
In the first part of this contribution we outline the construction of a novel matrix associated with a graph, the entries of which give the probability of a random walk over the graphG starting at sitei to reach sitej inD ij steps. HereD ij is the distance between verticesi, j.
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Interval Estimation with Restricted Randomization Rules

Biometrika, 1989
SUMMARY In comparing two treatments in a clinical trial, suppose that patients are assigned sequentially to treatments by a restricted randomization rule. Exact and approximate confidence intervals for treatment difference are derived without assuming that the study subjects were obtained by random sampling from a well-defined population. We show that,
R. T. Smythe, L. J. Wei, Cyrus R. Mehta
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Classification by restricted random walks

Pattern Recognition, 2003
We define a random walk in a data set of a metric space. In order that the random walk depends on the pattern of the data, restrictions are imposed during its generation. Since such a restricted random walk investigates only a local subset of the data, a series of random walks has to be realized for describing the entire data set.
Joachim Schöll, Elisabeth Schöll-Paschinger   +1 more
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Random Mappings with Restricted Preimages [PDF]

, 2012
In this paper we refer to finite endofunctions where each image has at most r preimages as r-mappings. Probabilistic analysis of these mappings provides heuristics for problems arising in cryptography which involve similar but more complicated classes of mappings.
Andrew MacFie, Daniel Panario
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Restricted Random Reinforcement in Probability Learning

Psychological Reports, 1965
An exact frequency ratio of 3:1 was maintained between reinforcing events over successive blocks of 4, 8, 16, or 128 trials in a two-choice verbal conditioning situation. No effect of such restricted randomization was found upon the mean learning curves, total number of responses, or variance in total number of responses.
Harry L. Madison, Marcia D. Johns
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Normalized Restricted Random Testing

2003
Restricted Random Testing (RRT) is a new method of testing software that improves upon traditional random testing (RT) techniques. This paper presents new data in support of the efficiency of RRT, and presents a variation of the algorithm, Normalized Restricted Random Testing (NRRT).
Kwok-Ping Chan, Dave Towey, Tsong Yueh Chen   +2 more
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