mat.ncssvar {dae} | R Documentation |

## Calculates the variance matrix of the random effects for a natural cubic smoothing spline

### Description

Calculates the variance matrix of the random effects for a
natural cubic smoothing spline. It is the tri-diagonal matrix
`\bold{G}_s`

given by Verbyla et al., (1999) multiplied by
the variance component for the random spline effects.

### Usage

`mat.ncssvar(sigma2s = 1, knot.points, print = FALSE)`

### Arguments

`sigma2s` |
A |

`knot.points` |
A |

`print` |
A |

### Value

A `matrix`

containing the variances and covariances of the
random spline effects.

### Author(s)

Chris Brien

### References

Verbyla, A. P., Cullis, B. R., Kenward, M. G., and Welham, S. J. (1999).
The analysis of designed experiments and longitudinal data by using
smoothing splines (with discussion). *Journal of the Royal
Statistical Society, Series C (Applied Statistics)*, **48**, 269-311.

### See Also

### Examples

```
Gs <- mat.ncssvar(knot.points = 1:10)
```

*dae*version 3.2.28 Index]