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I was buying a used book through Amazon this evening. Three resellers offered the book at essentially the same price. Here were their ratings: 94% positive out of 85,193 reviews 98% positive out of 20,785 reviews 99% positive out of 840 reviews Which reseller is likely to give the best service? Before you assume it's
Testing whether a number is composite as an example of a zero knowledge proof. How ZKPs are used more generally.
There are two kinds of latitude: geocentric and astronomical. On a perfect sphere, they're the same, but on an oblate spheroid like Earth they're different.
The word "kayak" is a palindrome, but it isn't visually symmetric. The word "bud" is visually symmetric, but not a palindrome.
Where do you stand in order to minimize the expected distance to walk to catch the first elevator that arrives? Maybe not where you think.
Why does lining up two scales of a slide rule let you multiply numbers?
The soft maximum approximates the maximum function, and approaches it in the limit, but is easier to work with.
How would you allocate money to a set of independent assets with to minimize volatility if some assets are more volatile than others?
During WWII, statistician Abraham Wald told the RAF to add armor where it didn't seem planes needed it. But he was right.
Some problems simply have no solution. Some problems have no simple solution. Some problems have many solutions. ...
The ability to quick estimates is still valuable, maybe more valuable than it used to be.
The notation [x] reigned for nearly two centuries before being replaced by ⌊x⌋. Why the latter is much better and what else we might learn from its inventor.
The snowball strategy says to pay off your smallest debt first, then the next smallest, and so on until you're out of debt. When I first heard of this I thought it was silly. Clearly the optimal strategy is to pay off the debt with the highest interest rate first. That assessment is mathematically correct,
How can you tell whether a number is divisible by 7? Almost everyone knows how to easily tell whether a number is divisible by 2, 3, 5, or 9. A few less know tricks for testing divisibility by 4, 6, 8, or 11. But not many people have ever seen a trick for testing divisibility