Density function, distribution function, quantile function and
random generation for the reverse (or negative) Weibull
distribution with location, scale and shape parameters.
Location, scale and shape parameters (can be
given as vectors).
log
Logical; if TRUE, the log density is returned.
lower.tail
Logical; if TRUE (default), probabilities
are P[X <= x], otherwise, P[X > x]
Details
The reverse (or negative) Weibull distribution function with parameters
code{loc} = a, code{scale} = b and
code{shape} = s is
G(x) = exp{-[-(z-a)/b]^s}
for z < a and one otherwise, where b > 0 and
s > 0.
Value
drweibull and dnweibull give the density function,
prweibull and pnweibull give the distribution function,
qrweibull and qnweibull give the quantile function,
rrweibull and rnweibull generate random deviates.
Note
Within extreme value theory the reverse Weibull distibution (also
known as the negative Weibull distribution) is often referred to
as the Weibull distribution.
We make a distinction to avoid confusion with the three-parameter
distribution used in survival analysis, which is related by a
change of sign to the distribution given above.