ABSTRACT
This chapter deals with corroboration of results or verification that the changes made are effective. There are a few simple tools that can accomplish this simple but important step: Which includes Simple charts, Comparison of five before and five after samples and Comparison of twin sets. The chapter discusses a few simple methods that deal with the corroboration of results that do not require understanding of complicated statistical studies, aids, or analysis. It summarizes three easy methods that can be utilized to show (prove) that corrective changes that were made were effective. First, a presentation of a simple chart can be made by plotting the historic problem condition versus the correction history data. The second method consists of comparisons of five revised and five previous samples tested to the same test bogie. The third method is the use of a comparison of twin sets to describe data that cannot be visually or numerically expressed effectively.
