Just 100 years ago, very few statistical tools were available and the field was largely unknown. Since then, there has been an explosion in available tools, as well as ever-increasing awareness and use of statistics.

Although most readers of this column are looking to pick up new tools or improve their use of commonly applied ones, I thought it would be worth stepping back and talking about one that was used before we had so many options at our disposal: the i-test.

Like most early analysis tools, the i-test had to be simple to calculate because computers weren’t available. It returned a binary response—“pass” or “fail” in most cases—that was usually meant to confirm or deny some prior assumption. This equates to what we call the null and alternative hypotheses today.

However, even without a calculator or computer, in most cases this test was lightning-fast to use and virtually any employee had it at their disposal, unlike current statistical tools.

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