ppPositions {ppcc}

Plotting Point Positions

Description

Calculates plotting point positions according to different authors

Usage

ppPositions(
  n,
  method = c("Gringorton", "Cunane", "Filliben", "Blom", "Weibull", "ppoints")
)

Arguments

n

numeric, the sample size

method

a character string naming a valid method (see Details)

Details

The following methods can by selected:

"Gringorton" the plotting point positions are calculated as

m_i = \left(i - 0.44\right) / \left(n + 0.12\right)

"Cunane" the plotting point positions are calculated as

m_i = \left(i - 0.4\right) / \left(n + 0.2\right)

"Blom" the plotting point positions are calculated as

m_i = \left(i - 0.3175\right) / \left(n + 0.25\right)

"Filliben" the order statistic medians are calculated as:

m_i = \left\{ \begin{array}{l l} 1 - 0.5^{1/n} & i = 1 \\ \left(i - 0.3175\right)/\left(n + 0.365\right) & i = 2,\ldots, n - 1 \\ 0.5^{1/n} & i = n \\ \end{array}\right.

"ppoints" R core's default plotting point positions are calculated (see ppoints).

Value

a vector of class numeric that contains the plotting positions