Displaying 10 results from an estimated 10 matches for "fm1dnase1".
2009 Nov 09
1
Parameter info from nls object
...ental data I thought it to be interesting
to check the information provided by
the summary method programmatically.
Still I could not find out which method to
use to get to those data.
Example (not my real world data, but to show the point):
[BEGIN]
> DNase1 <- subset(DNase, Run == 1)
> fm1DNase1 <- nls(density ~ SSlogis(log(conc), Asym, xmid, scal), DNase1)
> summary(fm1DNase1)
Formula: density ~ SSlogis(log(conc), Asym, xmid, scal)
Parameters:
Estimate Std. Error t value Pr(>|t|)
Asym 2.34518 0.07815 30.01 2.17e-13 ***
xmid 1.48309 0.08135 18.23 1.22e-10 **...
2004 Jul 16
1
Does AIC() applied to a nls() object use the correct number of estimated parameters?
I'm wondering whether AIC scores extracted from nls() objects using
AIC() are based on the correct number of estimated parameters.
Using the example under nls() documentation:
> data( DNase )
> DNase1 <- DNase[ DNase$Run == 1, ]
> ## using a selfStart model
> fm1DNase1 <- nls( density ~ SSlogis( log(conc), Asym, xmid, scal ),
DNase1 )
Using AIC() function:
> AIC(fm1DNase1)
[1] -78.41642
Using number of estimable coefficients (including residual error):
> -2*logLik(fm1DNase1) + 2*(length(coef(fm1DNase1))+1)
[1] -76.41642
attr(,"df")
[1] 3
at...
2017 Apr 01
6
Intervalos de confianza de la varianza de los residuos en un modelo no lineal.-
Hola amigos,
Supongamos que se quiere ejecutar un modelo no lineal con nls. Pensemos en
el ejemplo de la ayuda:
DNase1 <- subset(DNase, Run == 1)
fm1DNase1 <- nls(density ~ SSlogis(log(conc), Asym, xmid, scal), DNase1)
summary(fm1DNase1)
Aquí se está modelando la densidad óptica de un ensayo relacionada de forma
no lineal (logística) con (el logaritmo) de la concentración de una
proteína.
¿Sabe alguien si existe una función que sirva para calcula...
2006 Jul 18
4
How can I extract information from list which class is nls
Hello!
I work with :
R : Copyright 2006, The R Foundation for
Statistical Computing
Version 2.3.1 (2006-06-01)
On Windows XP Professional (Version 2002) SP2.
At this moment I use the function "nls" combined
with a selfStar model (SSmicmen, related to
Michaelis-Menten equation, and provided by the
"stats" package).
When I realise the following operation (cf. p 59
of the
2012 Sep 19
0
Discrepancies in weighted nonlinear least squares
Dear all,
I encounter some discrepancies when comparing the deviance of a weighted and
unweigthed model with the AIC values.
A general example (from 'nls'):
DNase1 <- subset(DNase, Run == 1)
fm1DNase1 <- nls(density ~ SSlogis(log(conc), Asym, xmid, scal), DNase1)
This is the unweighted fit, in the code of 'nls' one can see that 'nls'
generates a vector wts <- rep(1, n).
Now for a weighted fit:
fm2DNase1 <- nls(density ~ SSlogis(log(conc), Asym, xmid, scal), D...
2013 Feb 12
0
Deviance and AIC in weighted NLS
Dear All,
I encounter some discrepancies when comparing the deviance of a weighted and
unweigthed model with the AIC values. A general example (from 'nls'):
DNase1 <- subset(DNase, Run == 1)
fm1DNase1 <- nls(density ~ SSlogis(log(conc), Asym, xmid, scal), DNase1)
Now for a weighted fit:
fm2DNase1 <- nls(density ~ SSlogis(log(conc), Asym, xmid, scal),
DNase1, weights = rep(1:8, each = 2))
in which I assign increasing weights for each of the 8 concentrations with 2
repli...
2004 Jul 16
0
Does AIC() applied to a nls() object use the correctnumber of estimated parameters?
...ects using
> > AIC() are based on the correct number of estimated parameters.
> >
> > Using the example under nls() documentation:
> >
> > > data( DNase )
> > > DNase1 <- DNase[ DNase$Run == 1, ]
> > > ## using a selfStart model
> > > fm1DNase1 <- nls( density ~ SSlogis( log(conc), Asym,
> xmid, scal ),
> > DNase1 )
> >
> > Using AIC() function:
> >
> > > AIC(fm1DNase1)
> > [1] -78.41642
> >
> > Using number of estimable coefficients (including residual error):
> >
> &...
2006 Apr 18
1
Nonlinear Regression model: Diagnostics
Hi,
I am trying to run the following nonlinear regression model.
> nreg <- nls(y ~ exp(-b*x), data = mydf, start = list(b = 0), alg = "default", trace = TRUE)
OUTPUT:
24619327 : 0
24593178 : 0.0001166910
24555219 : 0.0005019005
24521810 : 0.001341571
24500774 : 0.002705402
24490713 : 0.004401078
24486658 : 0.00607728
24485115 : 0.007484372
2003 May 21
2
Access Object's Objects HELP
Dear WizaRds,
A run of nls produces the following concise summary:
> summary(cs.wt)
Formula: 0 ~ wt.MM(conc, time, A1, a1, A2, a2)
Parameters:
Estimate Std. Error t value Pr(>|t|)
A1 4.814e+02 2.240e+01 21.495 0.0296 *
a1 7.401e-01 7.435e-02 9.956 0.0637 .
A2 1.613e+02 1.738e+01 9.280 0.0683 .
a2 1.770e-02 7.324e-03 2.417 0.2497
2008 Sep 10
3
writing simple function through script
Hi all,
I try to write a simple function in a script. The script is as follows
yo<-function(Xdata)
{
n<-length(Xdata[,1])
Lgm<-nls(formula=LgmFormula,
data=Xdata,
start=list(a=1500,b=0.1),weights=Xdata$Qe)
return(Lgm)
}
After the execution of the script, when I call the function yo on data
called NC60.DATA I get an error.
#yo(NC60.DATA)
Erreur dans eval(expr, envir, enclos)