B_05_qq {lattice} | R Documentation |

## Quantile-Quantile Plots of Two Samples

### Description

Quantile-Quantile plots for comparing two Distributions

### Usage

```
qq(x, data, ...)
## S3 method for class 'formula'
qq(x, data, aspect = "fill",
panel = lattice.getOption("panel.qq"),
prepanel, scales, strip,
groups, xlab, xlim, ylab, ylim, f.value = NULL,
drop.unused.levels = lattice.getOption("drop.unused.levels"),
...,
lattice.options = NULL,
qtype = 7,
default.scales = list(),
default.prepanel = lattice.getOption("prepanel.default.qq"),
subscripts,
subset)
## S3 method for class 'data.frame'
qq(x, data = NULL, formula = data, ...)
```

### Arguments

`x` |
The object on which method dispatch is carried out. For the |

`data` |
For the |

`formula` |
The formula to be used for the |

`f.value` |
An optional numeric vector of probabilities, quantiles corresponding
to which should be plotted. This can also be a function of a single
integer (representing sample size) that returns such a numeric
vector. A typical value for this argument is the function
f.value = function(n) ppoints(n, a = 1) This has the effect of including the minimum and maximum data values
in the computed quantiles. This is similar to what happens for
For large |

`panel` |
A function, called once for each panel, that uses the packet (subset
of panel variables) corresponding to the panel to create a display.
The default panel function |

`qtype` |
The |

`aspect` |
See |

`prepanel` |
See |

`scales` |
See |

`strip` |
See |

`groups` |
See |

`xlab` , `ylab` |
See |

`xlim` , `ylim` |
See |

`drop.unused.levels` |
See |

`lattice.options` |
See |

`default.scales` |
See |

`subscripts` |
See |

`subset` |
See |

`default.prepanel` |
Fallback prepanel function. See |

`...` |
Further arguments. See corresponding entry in |

### Details

`qq`

produces Q-Q plots of two samples. The default behaviour of
`qq`

is different from the corresponding S-PLUS function. See the
entry for `f.value`

for specifics.

This and all other high level Trellis functions have several
arguments in common. These are extensively documented only in the
help page for `xyplot`

, which should be consulted to learn more
detailed usage.

### Value

An object of class `"trellis"`

. The
`update`

method can be used to
update components of the object and the
`print`

method (usually called by
default) will plot it on an appropriate plotting device.

### Author(s)

Deepayan Sarkar Deepayan.Sarkar@R-project.org

### See Also

`xyplot`

, `panel.qq`

,
`qqmath`

, `Lattice`

### Examples

```
qq(voice.part ~ height, aspect = 1, data = singer,
subset = (voice.part == "Bass 2" | voice.part == "Tenor 1"))
```

*lattice*version 0.22-6 Index]