Displaying 1 result from an estimated 1 matches for "laptop_sale".
2012 Nov 28
1
Problems with nls
The problem is badly scaled -- parameters from very small to very big.
nlmrt package manages a bit better, but scaling would likely make it and
nls both happier. nlxb insists on having its data in a data frame.
Here's my code
rm(list=ls())
Laptop_sale <- c(1405,
1863,2027,2669,2938,5275,6595,6943,8621,10905,12420,22400,32380,31600,34900,43163,47838,47592)
CuSale <- Laptop_sale
time <- seq_along(Laptop_sale)
Bass.Model <- Laptop_sale ~ m * ((p + q)^2/p) * (exp(-(p + q) * time)/((q /
p) * exp(-(p + q) * time) + 1)^2)
Bass.Fit <- nls...