選別精度の表示法に関する考察

空気動ジグの選別能力の研究 (第5報)

抄録

Author has been made the calculation and observation for regression lines and coefficient of correlation of 430 examples of Tromp's distribution curves which is obtained from the results of experiment for 53 Nos. of Jig. washers being used in industrial operation.
Basing on these results, author has been observed the statistical testing for distribution of these coefficient of correlation.
As the result of this testing, it is proved that the distribution of coefficient of correlation is subjected to logarithmic normal distribution with size constitution range (Rd) is less than 1.15, where, Rd= (Max. size-Min. size)/average size.
Beside, Ep (Terra coefficient) is represent quartile deviation of logarithmic normal distribution will be represented in the formula [log (D₇₅-1)-log (D₅₀-1)].
Ep will not be representable figure to show the width of distribution for Tromp's curve. I value will be representable value showing the width of distribution, but the absolute figure is completely differ from the Ep value for normal distribution and not be reasonable method representing the separation accuracy.
As a conclusion, author propose a method representing the separation accuracy with standard deviation figure or quartile deviation figure of Tromp's curve.
The appraisement of separating result in case of Rd>1.15 should be calculated by average random variable obtainable from the composited Tromp's curve within Rd<1.15.