Numb3rs
This is a blog where a professor from Northeastern University's Math department posts mathematical comments on the television show "Numb3rs". To comment, write to bridger@neu.edu.
Unique visitors since 6/14/2005: 
October 29, 2006
Parimutuel betting, which was part of the theme of last Friday's Numb3rs, is basically a very simple and arguably progressive (at least in the sphere of gambling) idea. Instead of the odds on a race (and hence the payoff) being set by professional gamblers, they are determined by the people who do the betting. The more money that is bet on a particular horse, the shorter (more favorable) the odds on that horse, hence the smaller the payoff should that horse win. Here's a simple example... continued »
October 26, 2006
Music players have a setting that allows them to play the tracks on a media item in some random or scrambled or shuffled order. I'd like to discuss how this works.
Suppose, for simplicity, that there are only 3 tracks: 1, 2 and 3. There are six ways of arranging them for play:
[1,2,3], [1,3,2], [3,2,1], [2,1,3], [3,1,2], [2,3,1]
The device must pick one of these 6 arrangements --- they're called permutations --- at random... continued »
October 25, 2006
In last Friday's (October 20) episode, there was a lot of talk about randomness and a sequence of events being "too random." What's this about?
First of all, a sequence of items is simply a list of things, where the order makes a difference... continued »
October 21, 2006
In last night's episode, both Charlie and Amita try to analyze traffic flow mathematically by applying the "partial differential equations" of fluid dynamics. This is a topic I discussed last May; please see the blog
Fluid Dynamics (5/13/06) .
That blog noted that even though liquids are made of individual discrete atoms, they behave "continuously" as fluids... continued »
October 20, 2006
On this show there was also a reference to messages hidden in pictures. I discussed this in a previous blog about a year ago:
Steganography (11/19/05).
October 17, 2006
The thighbone or femur can pivot (within limits) around the hip. The other end of the femur meets the knee, so the knee can trace (roughly) a part of a circle around the hip. On the other hand, the knee itself is a joint around which the tibia or shin bone can pivot. The other end of the tibia is the ankle. Thus, the ankle can trace a part of a circle around the knee while the the knee can trace part of a circle around the hip... continued »
October 15, 2006
The past episode ("Mole") referred to all sorts of mathematics.
There was a reference, once again, to face recognition algorithms... continued »
October 10, 2006
It is not surprising the mathematics can be used to detect art fraud. It is clear that different artists have different painting/drawing techniques, even when they belong to the same "school" (classicism, impressionism, cubism, abstract-expressionism etc.) It is similar in music. I am not an expert, but in many cases I can hear an unfamiliar work and have a pretty good idea who composed it... continued »
October 1, 2006
As I mentioned in the last blog, the path of the police in chasing a smuggler (or "rum-runner" or trawler) must have the property that its distance from the island at any time is the same as the distance of the smuggler... continued »
