Not everything is to be had for a dollar, but rarely is anything priced above $10. But there is a cost. Dollar General’s aggressive pricing drives locally owned grocery stores out of business, replacing shelves stocked with fresh fruit, vegetables and meat with the kinds of processed foods underpinning the country’s obesity and diabetes crisis. Above: Burton, Kansas, where the last food shop closed 20 years ago.

Gosset published his most important paper, The Probable Error of a Mean, under the pseudonym “Student” in the journal Biometrika in 1908.