pc function

pc

Coefficient $p_c$ of eq. (15.15) in Eichner (2017).

pc(cc)

Arguments

• cc: Numeric vector.

Returns

Vector of same length and mode as cc.

Details

p_c = 1/5 * (3c^2 - 5) / (3 - c^2) * c^2.

For further details see p. 297 f. in Eichner (2017) and/or Eichner & Stute (2013).

Note

$p_c$ should be undefined for $c = \sqrt 3$, but pc

is here implemented to return Inf in each element of its return vector for which the corresponding element in cc

contains R's value of sqrt(3).

Examples

c0 <- expression(sqrt(5/3))
c1 <- expression(sqrt(3) - 0.01)
cgrid <- seq(1.325, 1.7, by = 0.025)
cvals <- c(eval(c0), cgrid, eval(c1))

plot(cvals, pc(cvals), xaxt = "n", xlab = "c", ylab = expression(p[c]))
axis(1, at = cvals, labels = c(c0, cgrid, c1), las = 2)