The functions dLOGITNO
, pLOGITNO
, qLOGITNO
and rLOGITNO
define the density, distribution function, quantile function and random
generation for the logitnormal distribution.
The function LOGITNO
can be used for fitting the distribution in gamlss()
.
1 2 3 4 5 
mu.link 
the link function for mu 
sigma.link 
the link function for sigma 
x,q 
vector of quantiles 
mu 
vector of location parameter values 
sigma 
vector of scale parameter values 
log, log.p 
logical; if TRUE, probabilities p are given as log(p). 
lower.tail 
logical; if TRUE (default), probabilities are P[X <= x], otherwise, P[X > x] 
p 
vector of probabilities. 
n 
number of observations. If 
The probability density function in LOGITNO
is defined as
f(ymu,sigma)=(1/(y*(1y)*sqrt(2*pi)*sigma))*exp(0.5*((log(y/(1y))log(mu/(1mu))/(sigma))^2)
for 0<y>1, mu=(0,1) and σ>0.
LOGITNO()
returns a gamlss.family
object which can be used to fit a logitnormal distribution in the gamlss()
function.
Mikis Stasinopoulos, Bob Rigby
Rigby, R. A. and Stasinopoulos D. M. (2005). Generalized additive models for location, scale and shape,(with discussion), Appl. Statist., 54, part 3, pp 507554.
Stasinopoulos D. M., Rigby R.A. and Akantziliotou C. (2006) Instructions on how to use the GAMLSS package in R. Accompanying documentation in the current GAMLSS help files, (see also http://www.gamlss.org/).
Stasinopoulos D. M. Rigby R.A. (2007) Generalized additive models for location scale and shape (GAMLSS) in R. Journal of Statistical Software, Vol. 23, Issue 7, Dec 2007, http://www.jstatsoft.org/v23/i07.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18  # plotting the d, p, q, and r functions
op<par(mfrow=c(2,2))
curve(dLOGITNO(x), 0, 1)
curve(pLOGITNO(x), 0, 1)
curve(qLOGITNO(x), 0, 1)
Y< rLOGITNO(200)
hist(Y)
par(op)
# plotting the d, p, q, and r functions
# sigma 3
op<par(mfrow=c(2,2))
curve(dLOGITNO(x, sigma=3), 0, 1)
curve(pLOGITNO(x, sigma=3), 0, 1)
curve(qLOGITNO(x, sigma=3), 0, 1)
Y< rLOGITNO(200, sigma=3)
hist(Y)
par(op)

Questions? Problems? Suggestions? Tweet to @rdrrHQ or email at ian@mutexlabs.com.
All documentation is copyright its authors; we didn't write any of that.