Joint Density of Bivariate Gaussian Random Variables
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This Demonstration shows a 3D plot and a plot of a bivariate Gaussian (normal) density with zero means. You can drag the sliders for the standard deviations 
and 
and correlation coefficient 
for the random variables.
Contributed by: John M. Shea (March 2011)
Open content licensed under CC BY-NC-SA
Snapshots
Details
Some things to try:
1. Start with the default variances of 1 and note the effect of changing the correlation coefficient. What are the possible angles of the major axis of the ellipses you create?
2. Now set the correlation coefficient to a value close to 
. Then adjust the standard deviations for the two random variables. What are the possible angles of the major axis of the ellipses you create?
3. Now set the correlation coefficient to a value close to 
. Then adjust the standard deviations for the two random variables. What are the possible angles of the major axis of the ellipses you create?
Permanent Citation
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