goodmath

You might remember my post last week about [conservatives who can't subtract][subtract]: in particular, about how a conservative blogger who goes by "Captain Ed" attacked John Edwards for saying there are 37 million people in poverty in the US. It turned out that good ol' Ed wasn't capable of doing…

*(This post has been modified to correct some errors and add some clarifications in response to comments from alert readers. Thanks for the corrections!)* Today, we're going to take a brief diversion from category theory to play with some logic. There are some really neat connections between…

There's been a bunch of discussion here at ScienceBlogs about whether or not mathematicians are qualified to talk about evolution, triggered by [an article by ID-guy Casey Luskin][luskin]. So far, [Razib at Gene Expression][gnxp], [Jason at][evblog1][EvolutionBlog][evblog2], and [John at Stranger…

Over at fellow SBer {Worlds Fair][worldsfair}, they've put up an unofficial "Ask a ScienceBlogger" question, about childrens books: Are there any children's books that are dear to you, either as a child or a parent, and especially ones that perhaps strike a chord with those from a science…

Via [Migrations][migrations], I've found out about a really beautiful computational biology paper that very elegantly demonstrates how, contrary to the [assertions of bozos like Dembski][dembski-nfl], an evolutionary process can adapt to a fitness landscape. The paper was published in the PLOS…

In real life, I'm not a mathematician; I'm a computer scientist. Still a math geek, mind you, but what I really do is very much in the realm of applied math, researching how to build systems to help people program. One of my pathological obsessions is programming languages. Since I first got…

Last night, a reader sent me a link to *yet another* wretched attempt to argue for the existence of God using Bayesian probability. I *really* hate that. Over the years, I've learned to dread Bayesian arguments, because *so many* of them are things like this, where someone cobbles together a pile…

Longtime readers of GM/BM will remember [this post][homeland], where I discussed the formula used by the Department of Homeland Security for allocating anti-terrorism funds. At the time, I explained: >It turns out that the allocation method was remarkably simple. In their >applications for…

One of the questions that a ton of people sent me when I said I was going to write about category theory was "Oh, good, can you please explain what the heck a *monad* is?" The short version is: a monad is a category with a functor to itself. The way that this works in a programming language is that…

This is a repost from GM/BMs old home; the original article appeared [here][old]. I'm reposting because someone is attempting to respond to this article, and I'd rather keep all of the ongoing discussions in one place. I also think it's a pretty good article, which some of the newer readers here…

This has been written about [elsewhere][lf], but I can't let such a perfect example of the fundamental innumeracy of so many political pundits pass me by without commenting. Captain Ed of [Captains Quarters][cq] complains about a speech by John Edwards in which Edwards mentions 37 million people…

So, at last, we can get to Yoneda's lemma, as I [promised earlier][yoneda-promise]. What Yoneda's lemma does is show us how for many categories (in fact, most of the ones that are interesting) we can take the category C, and understand it using a structure formed from the functors from C to the…

Today's contribution on category theory is going to be short and sweet. It's an example of why we really care about [natural transformations][nt]. Remember the trouble we went through working up to define [cartesian categories and cartesian closed categories][ccc]? As a reminder: a [functor][…

Via [Feministe][feministe], we see a wingnut named Tim Worstall [trying to argue something about sexual education][worstall]. It's not entirely clear just what the heck he thinks his argument is; he wants to argue that sexual education "doesn't work"; his argument about this is based on abortion…

Just so folks know: ScienceBlogs is experimenting with some new anti-spam stuff, which should do away with the need for typekey. I've disabled typekey for Goodmath/Badmath, and we'll how it goes. If you've got cookies or cached data for the site, you might have a bit of trouble with comments for a…

About 10 days ago, I wrote a post about a group of bozos who believe they've found a secret code in the bible, and that according to them, there was going to be a nuclear attack on the UN building in NYC by terrorists. This was their fourth attempt to predict a date based on their oh-so-marvelous…

Or at least his financial advisers can. Kiplinger's, via MSN Money, are [reporting that Dick Cheney is betting that the economy is going to tank][cheney-invest]. When you take a look at the numbers: the deficit, the state of the dollar, the price of energy, stagnant wages, and the way that the…

It's friday again, so it's time for a random ten. So out comes my iPod, and the results are: 1. **Bela Fleck and the Flecktones, "Latitude"**: mediocre tune off of the latest Flecktones album. This album was a 3-CD set. Unfortunately, it really should have been a single CD; they just didn't bother…

As you can see, there's a new site banner. I got about a dozen submissions this time. They were all terrific, but something about this one just really grabbed me; it was absolutely exactly what I wanted. It was designed by Josh Gemmel. So Josh gets immortalized in the "about" tab of the blog. Any…

We're almost at the end of this run of category definitions. We need to get to the point of talking about something called a *pullback*. A pullback is a way of describing a kind of equivalence of arrows, which gets used a lot in things like interesting natural transformations. But, before we get to…

As lots of folks around SB have been commenting today, Nature magazine has come up with a list of the top 50 science blogs, based on technorati ratings. According to them, GM/BM is the number 45 science blog in the world. Even if it is a screwy way of figuring out what science blogs are most widely…

In comments to [my recent post about Gilder's article][gilder], a couple of readers asked me to take a look at a [DI promoted][dipromote] paper by Albert Voie, called [Biological function and the genetic code are interdependent][voie]. This paper was actually peer reviewed and accepted by a journal…

As several [other][panda] [folks][pz] have mentioned, George Gilder has written a [new anti-evolution article][gilder-article] which was published in the National Review. [panda]: http://www.pandasthumb.org/archives/2006/07/the_technogeek.html [pz]: http://scienceblogs.com/pharyngula/2006/07/…

As you may have noticed, there's a site banner up there now. I only received one submission back when I requested people to submit banners. , and it just didn't quite work for me. (Bit too dark, and I didn't like the hint of a blurring effect on the letters.) Since no one else sent me anything, I…

What's a subset? That's easy: if we have two sets A and B, A is a subset of B if every member of A is also a member of B. What's a subgroup? If we have two groups A and B, and the values in group A are a subset of the values in group B, then A is a subgroup of B. For any kind of thing **X**, what…

Earlier this week, I posted [a brief article][nyc-boom] about the ["True Bible Code"][tbc] folks who claimed that NYC was going to be hit by a terrorist nuclear weapon this weekend. I was looking at the rest of their site to see what their "true bible code" was. I was expecting something along…

It's that time of the week again, when I bore you with my bizzare taste in music. Quite an eclectic mix this week. Spock's Beard, "Thoughts". A track from an oldish Spock's Beard album. SB is an American neoprog band, which sounds something like a blend of old Genesis, Kansas, and Rush. Very good…

This is the last time I'm going to bug folks to remind them to donate to the SB challenges. The DonorsChoose fundraiser here at ScienceBlogs is just about over. Three more days for you to help some kids get a good education in math and science. The GoodMath/BadMath challenge is here; and Janet has…

Dishonest Dembski:the Universal Probability Bound One of the dishonest things that Dembski frequently does that really bugs me is take bogus arguments, and dress them up using mathematical terminology and verbosity to make them look more credible. An example of this is Dembski's *universal…

As I've frequently said, statistics is an area which is poorly understood by most people, and as a result, it's an area which is commonly used to mislead people. The thing is, when you're working with statistics, it's easy to find a way of presenting some value computed from the data that will…