Knowing all these sorting algorithms should come in handy next time you decide to alphabetize your bookshelf. Like President Obama, you’ll know not to use Bubble Sort. Instead, a good strategy—ratified by human and machine librarians alike—is to Bucket Sort until you get down to small enough piles that Insertion Sort is reasonable, or to have a

If a randomly generated tweak to our travel route results in an improvement, then we always accept it, and continue tweaking from there. But if the alteration would make thing a little worse, there’s still a chance that we go with it anyway (although the worse the alteration is, the smaller the chance).

overfitting poses a danger any time we’re dealing with noise or mismeasurement—

The takeaways are several. For one, be wary of cases where public information seems to exceed private information, where you know more about what people are doing than why they’re doing it, where you’re more concerned with your judgments fitting the consensus than fitting the facts.

However, in a Vickrey auction, the winner ends up paying not the amount of their own bid, but that of the second-place bidder. That is to say, if you bid $25 and I bid $10, you win the item at my price: you only have to pay $10. To a game theorist, a Vickrey auction has a number of attractive properties. And to an algorithmic game theorist in

These two principles are called responsiveness and throughput: how quickly you can respond to things, and how much you can get done overall. Anyone who’s ever worked in an office environment can readily appreciate the tension between these two metrics. It’s part of the reason there are people whose job it is to answer the phone: they are responsive

And it gives a remarkably straightforward solution to the problem of how to combine preexisting beliefs with observed evidence: multiply their probabilities together.

any optimal stopping problem, the crucial dilemma is not which option to pick, but how many options to even consider.

these decreases are “the result of lifelong selection processes by which people strategically and adaptively cultivate their social networks to maximize social and emotional gains and minimize social and emotional risks.” What Carstensen and her colleagues found is that the shrinking of social networks with aging is due primarily to “pruning”