MacBrownian Cocoa for Mac

From John Johnson:

MacBrownianMotion is a small educational tool aimed at helping you understand one of the most widely used "noise" models--Brownian motion. Brownian motion is used to model anything from the movement of amoebas to stock market prices.

Brownian motion is perhaps described as follows: stand at a point and flip a coin. If you get heads, then walk one foot left. If you get tails, then walk one foot to the right. Wait one second and repeat. This is called a random walk.

Now imagine that, instead of the above, you waited a half second and walked only a half foot in either direction. You are getting closer to Brownian motion. Now cut the time to a quarter second, and walk only a quarter foot. And so forth. Each time you cut the time and distance, you get something that looks more like Brownian motion.

Instead of wearing out your feet, try this program instead. It also simulates reflected Brownian motion (imagine bouncing off a wall--ouch!) and 2D Brownian motion (to model those amoebas).

If you use it and like it, then send me an email.