This question was just migrated to stackoverflow (well, an hour ago).
As far as I can see a great deal of it's pretty solidly on topic here.
"What is this function called?" is not a SO question, it's a CV question.
"Is this function linearizable?" --- there's no way that's an SO question. It's a stats question. How are SO people to be expected to talk about the fact that it depends on how the error enters the model?
"How do I estimate the parameters?" (paraphrasing) is a statistics question.
Those are right in the title.
There's code in the question, but the code related parts are not central to the statistical aspects, and the existence of code -- or even a question about code -- doesn't mean the statistical aspects don't belong here. At most I think the OP could have been encouraged to separate some aspects of the question off, but we have no business sending stats questions to SO.
Anyone involved, please take a look at my answer, and explain to me how a question which has an answer like that belongs anywhere but here -- because if that's our standard, I clearly have no clue whatever how any of this works.
Please help me understand the basis for this choice. I really don't understand how those questions at least don't belong here.
(I happen to feel that some of the remainder also belongs here, because it also contains some statistical aspects, but the parts I mentioned should be sufficient.)