plot.qqline {sma} | R Documentation |

## Add Line Going Through the Quantiles of a Q-Q Plot

### Description

This function adds a line to a quantile-quantile plot which passes
through user defined quantiles. This function is similar to, but
more general than, `qqline`

because the reference
distribution need not be the standard normal distribution and the
quantiles need not be the first and third quartiles.

Graphical parameters may be given as arguments to `plot.qqline`

.

### Usage

plot.qqline(x, y, a=0.25, ...)

### Arguments

`x` |
the reference (first) sample for the Q-Q plot, for a normal Q-Q
plot this would be the quantiles of a N(0,1) random sample. |

`y` |
the data. |

`a` |
a number between 0 and 1. A line is drawn which connects the
`a` and `1-a` quantile points. The default line passes
through the first and third quantiles. |

`...` |
graphical parameters may also be supplied as arguments
to the function (see `par` ). |

### See Also

`qqplot`

, `qqnorm`

, `qqline`

.

### Examples

data(MouseArray)
# mouse.setup <- init.grid()
# mouse.data <- init.data() ## see \emph{init.data}
# mouse.lratio <- stat.ma(mouse.data, mouse.setup)
## Calculation of t-statistics
## cl <- c(rep(1,3), rep(2,3))
## mouse.t2 <- stat.t2(mouse.lratio, cl)
## Diagnostic plots
plot.qq(mouse.t2$t, "Mouse")
## Using the QQline function
q <- quantile(rnorm(1000))
plot.qqline(q, mouse.t2$t)

[Package

*sma* version 0.5.15

Index]