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Normally this newsletter would be concerned with events in the wider world. But right now I just have to write about the shocking death — reportedly by suicide — of my former Princeton colleague, the economist Alan Krueger, at the age of 58.

I thought I knew Alan reasonably well and never saw a hint that something like this might be coming. But people’s lives often feel very different from the inside than they look on the outside.

What I can talk about is Alan’s work and why it mattered so much to other economists, myself very much included. For his research arguably did more to change how we view the economy than that of any other modern economist.

Alan’s most influential, paradigm-shifting work was his 1992 study with David Card on the effects of minimum-wage increases.