Management requires prediction. However, when making predictions it is easy to torture the data until they surrender and tell you what you expect to hear. Even though this torture may be unintentional, it can keep you from hearing the story the data could tell. This column is about how to avoid torturing your data while making predictions.

A few years ago a correspondent sent me the data for the number of major North Atlantic hurricanes for a 65-year period. Major hurricanes are those that make it up to category 3 or higher. I have updated this data set to include the number of major hurricanes through 2021. The counts of these major hurricanes are shown in a histogram in figure 1. In what follows we shall look at two approaches to using these data to make predictions.

Figure 1: Major North Atlantic hurricanes per year, 1935–2021

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