Stopping rules

By contrast, the frequentist view is often contrary to common sense and common scientific practice. The classic example of this is the stopping rule problem [42]. If I am... 

I. Bondarenko, H. Van Malderen, B. Treiger, P. Van Espen and R. Van Grieken, Hierarchical cluster analysis with stopping rules built on Akaike s information criterion for aerosol particle classification based on electron probe X-ray microanalysis. Chemom. Intell. Lab. Syst., 22 (1994) 87-95. 

In this example, two principal components are arbitrarily selected. More or fewer may be necessary, and this is a function of a predetermined stopping rule for extraction of principal components from X. In SIMCA method, a cross validation technique (2) is used. 

Defining stopping rules in advance is undoubtedly difficult in 1998 Suter wrote that Step 6 of the DQO process had never been completed for an ecological risk assessment. Unless this obstacle can be overcome, frequent consultation between risk assessors and managers will be needed during each assessment to avoid over-refining it (ECOFRAM 1999). 

Mojena, R. Hierarchical grouping methods and stopping rules An evaluation. The Computer Journal, 1977,20,359-363. 

A trial may need to be stopped early if a treatment has serious adverse effects, or if there is clear benefit. However, as is seen in Fig. 18.1, the chance fluctuations during the early stages of a trial can easily reach statistical significance at the p = 0.05 level. If the stopping rule is based on a p value of 0.05, it is quite possible that the trial will be stopped early, and the wrong conclusions drawn. Stopping rules should be based on significance levels ofp < 0.01... 

Costanza, M.C. and A.A. Afifi. 1979. Comparison of stopping rules in forward stepwise discrimination analysis./. Am. Stat. Assoc. 74 777-785. 

Stopping rule, for regression, 184 Student r-distribution, 7 Sums of products, 209 Sums of squares, 209... 

The main differences between the diverse designs encountered in drug development are related to the dose-escalation scheme, the number of patients per level, and the stopping rule definition. The oldest and most frequently used dose-escalation method for the last 20 years is the well known standard method based on Fibonacci series. Because of the limitations of this method, more sophisticated approaches have been developed, namely ... 

Modified CRM Because of ethical considerations, several modifications have been proposed with the objectives of reducing the risk for a patient to receive a toxic dose and of shortening the length of the trial. They concern the starting dose, the dose-escalation scheme, the stopping rules, and the parameterization of the dose-response model using more than one parameter. 

J. O Quigley and E. Reiner, A stopping rule for the continual reassessment method. Biometrika 85 741-748 (1998). 

S. Zohar and S. Chevret, The continual reassessment method comparison of Bayesian stopping rules for dose-ranging studies. Stat Med 20 2827-2843 (2001). 

S. Zohar, A. Latouche, M. Taconnet, and S. Chevret, Software to compute and conduct sequential Bayesian phase I or II dose-ranging clinical trials with stopping rules. Comput Methods Programs Biomed 72 117-125 (2003). 

F-to-remove values for the next candidate for elimination. This process continues until no variable can be removed since all i -to-remove values are greater than some specified maximum value. This is the stopping rule F-to-remove = 4 was employed here. 

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