The Nature of Computation - Intellects Vast and Warm and Sympathetic: "I hand you a network or graph, and ask whether there is a path through the network that crosses each edge exactly once, returning to its starting point. (That is, I ask whether there is a 'Eulerian' cycle.) Then I hand you another network, and ask whether there is a path which visits each node exactly once. (That is, I ask whether there is a 'Hamiltonian' cycle.) How hard is it to answer me?" (via) [more inside]
posted by kliuless on Dec 1, 2012 - 19 comments

"Normal" human pregnancies last 40 weeks, right? Well, no; they can vary quite a bit by the mother's race, age, number of previous children, family history of delivering early or late, home state, work habits, and even the fetus' HLA type. So where does that "40 week" thing come from? Oh, dear. So check out this super-nerdy pregnancy statistics website, from an engineer mom who is collecting data from the public (see the raw data and auto-generated graphs, and read the FAQ about the survey, with more cool graphs). Looking for day-by-day probabilities on when that baby's due? This would be your stats table with daily prediction (adjust dates at top of page as needed). Of course, you could always shut up your constantly inquiring relatives and friends another way.
posted by Asparagirl on Dec 16, 2010 - 45 comments

It has applications in Economics, Biology, Pharmaceuticals, and is rooted in State Space Modeling, which with Kalman Filtering (paper, breakdown [warning: long]) was used in the Apollo program. Dynamic Linear Models are gaining in popularity. There exists an R package, and both a short doc and a really great (read: worth buying) book (sorry, not a download, but here's chapter 2) by Giovanni Petris, Sonia Petrone, and Patrizia Campagnoli with its own little website.
posted by JoeXIII007 on Jul 30, 2010 - 14 comments

World Clock SWF application showing the time of day expressed in actual time, the number of species passed into extinction, barrels of oil produced, the temperature of the earth, prison population, world population, and deaths by various causes. Because, y'know, you weren't depressed enough already. Site also offers a number of free games, calculators and applications for your own site.
posted by psmealey on Jun 30, 2007 - 36 comments