Perhaps we are 75% sure that our conclusion is correct and that a campaign against eggplant would save a thousand American lives per year. But there’s also a 25% chance our conclusion is wrong; and if it’s wrong, we’ve induced many people to give up what might be a favorite vegetable, leading them to eat a less healthy diet overall, and causing, let’s say, two hundred excess deaths annually.* As always, we obtain the expected value by multiplying the result of each possible outcome by the corresponding probability, and then adding everything up. In this case, we find that 75% × 1000 + 25%
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