\(\begin{bmatrix}x_i \\ y_i\end{bmatrix} \sim \mathcal{N}\left( \begin{bmatrix}\mu_x \\ \mu_y \end{bmatrix}, \mathbf{\Sigma} = \begin{bmatrix}\sigma_x^2 & \rho \sigma_x \sigma_y \\ \rho \sigma_y \sigma_x & \sigma_y^2 \end{bmatrix} \right) \)

Pairs of observations \(x_i, y_i\) are drawn from a bivariate normal distribution with means \(\mu_x, \mu_y\) and variance-covariance matrix \(\mathbf{\Sigma}\).

\(\rho\)
"rho", correlation coefficient
\(\sigma_x\)
"sigma x", standard deviation of x
\(\sigma_y\)
"sigma y", standard deviation of y
\(\mu_x\)
"mu x", mean of x
\(\mu_y\)
"mu y", mean of y
plot
darker rings = greater probability; points are 100 random x,y pairs
math
math behind the simulation
code
R code for simulation

\(\rho\)
"rho", correlation coefficient
\(\sigma_x\)
"sigma x", standard deviation of x
\(\sigma_y\)
"sigma y", standard deviation of y
\(\mu_x\)
"mu x", mean of x
\(\mu_y\)
"mu y", mean of y

simulating bivariate data

A web app created in d3.js by Dale J. Barr

source code at github