Industrial Experimentation

The present Monograph is based on an earlier Memorandum produced by the Directorate of Ordnance Factories (Explosives) for the use, primarily, of those concerned with pilot plant and plant scale experiments on chemical manufacturing processes in the Royal Ordnance Factories (Explosives). Much work of this type was being carried out and it had become evident that it was desirable for the results of such experiments to be subjected to critical tests of significance. A convenient account of the straightforward tests of significance, written from the point of view of the individual who has to apply them in practice without necessarily a full knowledge of their theoretical background, was not readily available, and an attempt was therefore made to prepare one. It was evident that to apply tests of significance conveniently and economically the experiments had to be planned in appropriate forms. It is considered that the methods outlined should be as much a standard tool of the industrial experimenter as a chemical balance is of the laboratory experimenter. In carrying out an industrial experiment the choice is not between using a statistical design with the application of the appropriate tests of significance or the ordinary methods: the choice is between correct or incorrect methods. Even the simplest experiment requires an estimate of the significance of its results. The practice sometimes followed of consulting the statistician only after the experiment is completed and asking him "what he can make of the results" cannot be too strongly condemned. It is essential to have the experiment in a form suitable for analysis and in general this can only be attained by designing the experiment in consultation with the statistician, or with due regard to the statistical principles involved. The present Monograph, therefore, is intended to be a guide to both the planning and the interpretation of experiments on the industrial scale, and it is hoped that the methods described will become part of the everyday technique to those who carry out such experiments. R. C. BOWDEN, Director of Ordnance Factories (Explosives) Ministry of Supply