DNase1 <- DNase[ DNase$Run == 1, ]
## note that selfstarting models doesn't work yes % <<< FIXME !!!
##--- without conditional linearity ---
## classical
fm3DNase1 <- nls( density ~ Asym/(1 + exp(( xmid - log(conc) )/scal ) ),
data = DNase1,
start = list( Asym = 3, xmid = 0, scal = 1 ),
trace = TRUE )
summary( fm3DNase1 )
## robust
frm3DNase1 <- rnls( ~ density - Asym/(1 + exp(( xmid - log(conc) )/scal ) ),
data = DNase1, trace = TRUE,
start = list( Asym = 3, xmid = 0, scal = 1 ))
## FAILS (summary.nls): summary( frm3DNase1 )%% <<< FIXME
##--- using conditional linearity ---
## classical
fm2DNase1 <- nls( density ~ 1/(1 + exp(( xmid - log(conc) )/scal ) ),
data = DNase1,
start = c( xmid = 0, scal = 1 ),
alg = "plinear", trace = TRUE )
summary( fm2DNase1 )
## robust
if(FALSE) { # currently fails %% FIXME error in nls's nlsModel.plinear()
frm2DNase1 <- rnls( ~ density - 1/(1 + exp(( xmid - log(conc) )/scal ) ),
data = DNase1, start = c( xmid = 0, scal = 1 ),
alg = "plinear", trace = TRUE )
summary( frm2DNase1 )
} # not yet
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