Description Usage Arguments Value References Examples

View source: R/ellipse-functions.R

Draws a (1-`alpha`

)100% confidence ellipse (two dimensional) for a
multivariate normal distribution using the eigendecomposition of the
covariance matrix.

1 2 3 4 5 6 7 8 9 10 11 12 13 |

`X.mean` |
a column matrix giving the mean of the two dimensions of the p-dimensional multivariate normal distribution. |

`eig` |
the eigenvalues and eigenvectors of the covariance matrix. This
should be of the same form as the output of |

`n` |
the number of observations. |

`p` |
the number of dimensions of the multivariate normal distribution. (The resulting graph will always be a two-dimensional confidence region for the two dimensions of a p-dimensional multivaraite normal distribution under consideration.) |

`xl` |
a vector giving the lower and upper limits of the x-axis for
plotting. If |

`yl` |
a vector giving the lower and upper limits of the y-axis for
plotting. If |

`axes` |
logical. If |

`center` |
logical. If |

`lim.adj` |
a value giving an adjustment to the x-axis and y-axis limits
computed if either |

`alpha` |
a value giving the value of alpha to be used when computing the
contour. Contours are drawn at the |

`...` |
other arguments to be passed to the graphing functions. |

None

Johnson, R. A., & Wichern, D. W. (2007). Applied multivariate statistical analysis (6th ed). Pearson Prentice Hall.

1 2 3 4 5 6 7 8 9 10 | ```
# 90% Confidence Ellipse for Reading and Vocab from ability.cov
x.bar <- ability.cov$center[5:6]
Sigma <- ability.cov$cov[5:6,5:6]
n <- ability.cov$n.obs
p <- length(ability.cov$center)
confidenceEllipse(X.mean = x.bar,
eig = eigen(Sigma),
n = n, p = p,
alpha = 0.10)
``` |

Embedding an R snippet on your website

Add the following code to your website.

For more information on customizing the embed code, read Embedding Snippets.