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3D Normal Distribution

3D Normal Distribution

A teaching tool to show how a 3D normal function depends on the correlation coefficient between the two variables. The applet also realizes a Virtual Reality environment, i.e. the user can look at the function changing the point of view and the distance from the graph cliking the left button of the mouse wherever on the background.


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David Krider
David Krider (null)
20 years ago
Excellent use of three dimensions. This is an excellent manner in which to visualize the correlation parameter in a bivariate normal distribution
Dale Mead
Dale Mead (Student)
20 years ago
Very instructive Applet that will be even more valuable once perfected. This certainly does what it's intended to do. I'm having a little trouble with it on my computer, a Macintosh 5500/175 with OS 8.1 using Netscape 3.01. It refreshes about twice a second, which is too fast to be able to really look at it. The scroll bar on the right disappears and only partially reappears as it's being adjusted. The graphic itself might benefit from some representation of the coefficient the user is adjusting. Although the value of r changes in the bar below the image, if some line or bar could be seen changing within or alongside the image - rotating as the curve rotates to keep the correct orientation - the number at the bottom might have more meaning. (You could also add space to the left of the ""r"" in the field.) You might also want to include the equation that generates the curve, with the values changing dynamically to match the slider adjustment and changing surface. This applet is 90% there. I can't wait to see this when it's perfected!