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I have a linear but complex function in R, let's say

estimate.value <- function(x, y, z)

Now I have an output value and I want to estimate the input parameters one or two at a time. How do I do that?

e.g. I know that output value is 5 and and x=2, y=3 then how do I estimate z? or I know output value is 5 and only know x=2, how do I estimate x and y?

ZombieCoder
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  • Your question is not clear at all: first you assume that your function is linear. So it writes simply f(x) = t(u) %*% x , where u and x are vectors (u is fixed) and t is the transpose operator ? – Colonel Beauvel Dec 03 '14 at 15:32
  • What do you mean "linear but complex"? Is it linear in the variables, e.g. `f = a*x+b*y+c*z`, or is it linear in the parameters, e.g. `f = a*exp(x)+b*cos(x)+c*log(x)`. Best to just show the function in your question. – jlhoward Dec 03 '14 at 17:11

1 Answers1

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Your question essentially relates to inverting a function. You could do this by employing root-finding. Look here for an answer on SO regarding this.

Community
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Kees Mulder
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