I was able to solve this problem by going back to nls and obtaining the
initial parameter estimates through optim. When I used nlsList with my
dataset, it took 2 minutes to solve and was not limited by the bounds. Now I
have the bounds working and it takes 45 seconds to solve. Here is the new
I adapted a selfStart function and the lower bounds are not working. The
parameter b is negative, whereas I would like the lower bound to be zero.
Any ideas? Thanks.
Here is my code (I am still figuring out how to easily make replicable
examples):
A-1.75
mu-.2
l-2
b-0
x-seq(0,18,.25)
I tested the optim function and that is returning non-negative parameter
values (meaning they are bound by the lower limits), but I think those are
the starting estimates for the nlsList model which is then finding negative
values for the solution.
-
In theory, practice and theory are the
I ran the code again and got an error saying that the x was unknown. I
don't know why I hadn't seen that error before. Anyway, I made the edits to
func1 so instead of x, it is xy$x.
#function to optimize
func1 - function(value) {
A.s - value[1]
mu.s - value[2]
l.s - value[3]
b.s-
4 matches
Mail list logo
