February, 2008

Mechanical Turk

A few months ago, on a different blog I posted a method for reading books for free on Amazon. Hopefully they didn’t take offense to this but rather saw it for what I did which was a way to get people interested in a book enough to want to purchase it. But just in case Amazon has any hard feelings, I will make amends here by plugging one of their little-known but extremely powerful services called Mechanical Turk.

Mechanical Turk is matchmaker between people who have spare time do to tasks that humans are good at and people (or organizations) that need such tasks done. These HITs (Human Intelligence Tasks) range from doing research to giving opinions for a survey to beta testing a website to giving advice on a travel destination to whatever you can dream up.

If you want a task done, you simply post a HIT description, determine how many different people you want to respond and how much

What is a Gene?

Not having had any serious biological training I have to go to Wikipedia and Google to learn the basics. And I’m often surprised to find that concepts everyone uses don’t have good consensus amongst scientists. When reading the Wikipedia entry for “gene”, it occurs to me that if the concept didn’t predate the discovery of DNA, it would not exist.

At the very least, it would look much different than “a locatable region of genomic sequence, corresponding to a unit of inheritance” (call this the “standard definition”).

Gerstein’s definition, “a union of genomic sequences encoding a coherent set of potentially overlapping functional products,” while more accurate, is not really a useful definition. It just says there is structure to the information on a DNA sequence which corresponds to higher level function in the cell or organism. But we knew that already, it doesn’t tell us anything about the structure or how it relates to function.

The standard definition is a stronger claim, but

Parrondo's Paradox and Poker

Parrondo’s paradox is the well-known counterintuitive situation where individually losing strategies or deleterious effects can combine to win…. Over the past ten years, a number of authors have pointed to the generality of Parrondian behavior, and many examples ranging from physics to population genetics have been reported. In its most general form, Parrondo’s paradox can occur where there is a nonlinear interaction of random behavior with an asymmetry, and can be mathematically understood in terms of a convex linear combination.

From Developments in Parrondo’s Paradox (Derek Abbott)

One of my new favorite pastimes is identifying real world scenarios that I think are examples of Parrondo’s Paradox (PP). Here are some from the world of poker:

  • Morton’s Theorem describes situations during the play of hands wherein you may employ a strategy that is losing against two individual opponents, but against both simultaneously it’s a winning strategy.
  • There is a related scenario that exists in tournament poker known as

Complex Links: Cancer