Distribution of angles between unit vectors and the multiple comparison problem for unit vectors

We suppose that L x i = Fq(μi, KiK) for i=1,...,p, where the independent Fisher distributions on the unit sphere in Rq have modal vectors μi and known concentrations KiK, where K will be large—in fact, to obtain asymptotic distributions, we will let K tend to infinity. The term x'iXj=cos 0ij estimates cos 0ij= μiμy. The asymptotic joint distribution of the terms will be studied when all the vectors μi μ are distinct, and for the special case when all the vectors μi=μ, so that all the terms are zero. These very different results have a variety of applications as well as being interesting in themselves. One of these applications is the 'multiple comparisons problem' for unit vectors. However, it was found necessary to give here a different way of solving this problem.     

A New Look at Half-normal Plots for Assessing the Significance of Contrasts for Unreplicated Factorials

The visual inspection of a half-normal plot is a popular procedure for interpreting data from unreplicated factorial experiments. As this technique is somewhat subjective, the plot should preferably be supplemented with a more formal procedure. However, despite the improvements proposed by Zahn, the formal method using the half-normal plot suggested by Daniel seems to be rarely used. We investigate this procedure by using simulations and real data and suggest a modification to improve its acceptability. We also present corrected critical values for a procedure proposed by Lenth which was found to be miscalibrated.     

Bayesian sample-size determination for one and two Poisson rate parameters with applications to quality control

We formulate Bayesian approaches to the problems of determining the required sample size for Bayesian interval estimators of a predetermined length for a single Poisson rate, for the difference between two Poisson rates, and for the ratio of two Poisson rates. We demonstrate the efficacy of our Bayesian-based sample-size determination method with two real-data quality-control examples and compare the results to frequentist sample-size determination methods.     

A scientist's viewpoint on promoting effective use of experimental design: Ten things a scientist wants to know about experimental design

This paper tackles the practical application of statistical tools. Chemical development is a rich area for collaboration between statisticians and chemists, but most statisticians encounter difficulties in promoting the tools to this client group. This paper, presented from a chemist's perspective, is intended to help bridge the gap between the two professions. The paper explores differences in uptake and attitudes towards adopting these techniques and suggests what has hindered or helped the process of effective application of experimental design. Copyright © 2003 John Wiley & Sons, Ltd.     

Relationship,Language and Pre-Understanding in the Reflecting Processes

This article discusses whether the concepts ‘relationship’, ‘expressing oneself’ and ‘pre-understanding’ might be better starting points to describe and understand ‘the therapeutic process’ than the traditional concepts ‘theory’ and ‘method’. The discussion has emerged from participation in, and will itself clarify, theso-called “reflecting processes”.