Displaying 4 results from an estimated 4 matches for "nlsout".
2011 Jun 17
2
Non-linear Regression best-fit line
...01,13,20,24,37,42,48,61,72,86,90)
> lm(log(0-log(yy))~tt)
Call:
lm(formula = log(0 - log(yy)) ~ tt)
Coefficients:
(Intercept) tt
9.5029 -0.3681
However, when I plug those values into the nls function, I get an error message about the "getInitial" method
> nlsout<-nls(y~1*exp(-beta*exp(-gamma*t),start=c(beta=exp(9.5),gamma=.368)));summary(nlsout)
Error in getInitial.default(func, data, mCall = as.list(match.call(func, :
no 'getInitial' method found for "function" objects
Can anyone help clarify how I can find the parameters for a b...
2009 Oct 30
0
Interpreting gnls() output in comparison to nls()
...Memory 4.875197
21 24 T24-3 230.0 Memory 5.438079
22 48 T48-1 458.0 Memory 6.126869
23 48 T48-2 594.0 Memory 6.386879
24 48 T48-3 374.0 Memory 5.924256
>
------------------------------------
Now I fit nls() and gnls() to the data.
--------------------------------------
##Fit nls
> nlsOut =
+ nls(lnCount ~ log(C0[Type] + C1[Type] * Time + C2[Type]* Time^2),
+ start = list( C0 = c(exp(3.5), exp(3.5)), C1 = c(-0.01, -0.01), C2 =
c(0.01, 0.01)),
+ data = myPbmcData,
+ )
>
> summary(nlsOut)
Formula: lnCount ~ log(C0[Type] + C1[Type] * Time + C2[Type] * Time^...
2011 Sep 13
0
nls, the four parameter logisitc equation, and prediction band
...that contains the following two variables: time
(X value) and response (Y value). This is a fairly extensive file (with >
16000 entries). I have two questions:
1. I want to use the following equation to regress Y on X: Y-hat = min +
(max-min)/(1 + (X/EC50)^Hillslope).
Here is my R command:
nlsout <- nls(Y ~ (0 - (100-0)/(1 + (X/EC50)^hill)), start=c(EC50=125,
hill=-1))
However, I get the following error message:
Error in numericDeriv(form[[3L]], names(ind), env) :
Missing value or an infinity produced when evaluating the model
Could someone explain the error message to me, please, an...
2011 Sep 13
0
nls, the four parameter logistic equation, and prediction band
...ime
> (X value) and response (Y value). This is a fairly extensive file (with >
> 16000 entries). I have two questions:
>
> 1. I want to use the following equation to regress Y on X: Y-hat = min +
> (max-min)/(1 + (X/EC50)^Hillslope).
>
> Here is my R command:
>
> nlsout <- nls(Y ~ (0 - (100-0)/(1 + (X/EC50)^hill)), start=c(EC50=125,
> hill=-1))
>
> However, I get the following error message:
>
> Error in numericDeriv(form[[3L]], names(ind), env) :
> Missing value or an infinity produced when evaluating the model
> Could someone explain...