Adding one more method:

glm(y~ x1 + x2 + x3 - 1, family = gaussian(link = "inverse"), data = mydata)

will fit the exact model (including the desired error structure). The default GLM starting values usually work OK, but it is true that inverse-links can sometimes be more finicky than more typical links.

On 2023-08-19 6:48 p.m., John Fox wrote:
Dear John, John, and Paul,

In this case, one can start values by just fitting

 > lm(1/y ~ x1 + x2 + x3 - 1, data=mydata)

Call:
lm(formula = 1/y ~ x1 + x2 + x3 - 1, data = mydata)

Coefficients:
      x1       x2       x3
0.00629  0.00868  0.00803

Of course, the errors enter this model differently, so this isn't the same as the nonlinear model, but the regression coefficients are very close to the estimates for the nonlinear model.

Best,
  John


______________________________________________
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Reply via email to