create.qqplot.fit.confidence.interval {BoutrosLab.plotting.general}

Create the confidence bands for a one-sample qq plot

Description

Returns the values of constructing the confidence bands for a one-sample qq plot

Usage

create.qqplot.fit.confidence.interval(x, distribution = qnorm, conf = 0.95,
    conf.method = "both", reference.line.method = "quartiles");

Arguments

x

A numeric vector

distribution

A quantile function that takes a vector of probabilities as argument and produces the corresponding quantiles from a theoretical distribution, defaults to "qnorm", that is normal distribution.

conf

Confidence level, default to 0.95

conf.method

Methods used to draw confidence bands and must be one of "simultaneous", "pointwise", "both"(default).

reference.line.method

Methods used to draw reference line and must be one of "quartiles"(default), "diagonal", "robust".

Value

Returns the values of creating the upper and lower bands for the qq plot.

Warning

Note that this function works only for a single panel qq plot, not for grouped data and multi-qq plot.

Author(s)

Ying Wu

Examples

tmp.x <- rnorm(100);

tmp.confidence.interval <- create.qqplot.fit.confidence.interval(tmp.x);

qqnorm(tmp.x);
qqline(tmp.x);
lines(tmp.confidence.interval$z, tmp.confidence.interval$upper.pw, lty = 2, col = "brown");
lines(tmp.confidence.interval$z, tmp.confidence.interval$lower.pw, lty = 2, col = "brown");
lines(tmp.confidence.interval$z[tmp.confidence.interval$u], 
    tmp.confidence.interval$upper.sim, lty = 2, col = "blue");
lines(tmp.confidence.interval$z[tmp.confidence.interval$l], 
    tmp.confidence.interval$lower.sim, lty = 2, col = "blue");

legend(1, -1.5, c("simultaneous", "pointwise"), col = c("blue", "brown"), lty = 2, bty = "n");