Standard Errors of Differences

Abstract

Because of our feeling that standard errors should be closely associated with the statistics to which they pertain, this book was so arranged as to make it practicable to place the chapter on Statistical Inference near the beginning of the text—after only a few statistics (X̄, Mdn, s, and AD) had been presented. Subsequently, as new statistical terms were introduced they were usually accompanied by their standard errors. From these standard errors, it was a very simple matter to determine confidence limits whenever they were needed. And from these limits we could find out whether or not our sample statistic differed significantly from any hypothesized population parameter. But such parameters were always fixed points, not figures subject to variation, as the sample statistics were.