lndIChisq {bayesm} | R Documentation |

## Compute Log of Inverted Chi-Squared Density

### Description

`lndIChisq`

computes the log of an Inverted Chi-Squared Density.

### Usage

`lndIChisq(nu, ssq, X)`

### Arguments

`nu` |
d.f. parameter |

`ssq` |
scale parameter |

`X` |
ordinate for density evaluation (this must be a matrix) |

### Details

`Z = nu*ssq / \chi^2_{nu}`

with `Z`

`\sim`

Inverted Chi-Squared.

`lndIChisq`

computes the complete log-density, including normalizing constants.

### Value

Log density value

### Warning

This routine is a utility routine that does **not** check the input arguments for proper dimensions and type.

### Author(s)

Peter Rossi, Anderson School, UCLA, perossichi@gmail.com.

### References

For further discussion, see Chapter 2, *Bayesian Statistics and Marketing* by Rossi, Allenby, and McCulloch.

### See Also

### Examples

```
lndIChisq(3, 1, matrix(2))
```

[Package

*bayesm*version 3.1-6 Index]