Description Usage Arguments Details Value ACKNOWLEDGEMENT Author(s) References See Also Examples

Draws a normal quantile-quantile plot using symbols whose sizes are proportional to the probabilities that the associated observations were generated by the associated components of the model.

1 2 |

`object` |
An object of class |

`xlim` |
A numeric vector of length two, giving
the limits on the |

`ylim` |
A numeric vector of length two, giving
the limits on the |

`shape` |
The shape of the plotting symbol. May be abbreviated to the first
letter, i.e. |

`ngon` |
The "disc" shape is actually a regular polygon; ngon specifies how many sides it should have; ignored if shape is not equal to "disc". |

`size` |
A scale factor to change the absolute sizes of the plotting symbols; values larger than 1 make the symbols larger than the default; values less than 1 make them smaller. |

`...` |
Additional arguments to be passed to the polygon function which actually draws the plotting symbols. |

The plot produced is visually assessed by ignoring or discounting small symbols.

None. This function is called for its side effect of drawing a normal quantile-quantile plot.

The idea of creating residual plots for regression mixtures by making the symbol size proportional to the associated probability is due to Prof. Adrian Baddeley who was, at the time (2000) at the University of Western Australia. He is now (2021) at Curtin University.

Rolf Turner r.turner@auckland.ac.nz

T. Rolf Turner (2000). Estimating the rate of spread of a
viral infection of potato plants via mixtures of regressions.
*Applied Statistics* **49** Part 3, pp. 371 – 384.

`ncMcTest()`

,`cband()`

, `covMix()`

,
`mixreg()`

, `plot.cband()`

,
`plot.mixresid()`

, `qqMix()`

,
`residuals.mixreg()`

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 | ```
# Aphids.
fita <- mixreg(plntsInf~aphRel,ncomp=2,seed=42,data=aphids)
resa <- residuals(fita,std=TRUE)
qqMix(resa,size=2,shape="l")
qqMix(resa,shape="n",pch=7,cex=1.5)
# Kilns.
thStrt <- list(list(beta=c(26.1,48800),sigsq=0.58,lambda=0.33333333),
list(beta=c(23.5,32400),sigsq=0.58,lambda=0.33333333),
list(beta=c(-0.06,20760),sigsq=0.58,lambda=0.33333333))
fitk <- mixreg(y ~ x,ncomp=3,data=kilnAoneOut,thetaStart=thStrt)
## Not run: # Takes too long
resk <- residuals(fitk,std=TRUE)
qqMix(resk,shape="s")
qqMix(resk,shape="s",xlim=c(-0.25,0.9),ylim=c(-3,3))
qqMix(resk,shape="n")
## End(Not run)
``` |

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.