Property 1: Given samples {x1, …, xn} and {y1, …, yn} and let ŷ = αeβx, then the value of α and β that minimize (yi − ŷi)2 satisfy the following equations:
Proof: The minimum is obtained when the first partial derivatives are 0. Let
Thus we seek values for α and β such that and
; i.e.
Property 2: Under the same assumptions as Property 1, given initial guesses α0 and β0 forα and β, let F = [f g]T where f and g are as in Property 1 and
Now define the 2 × 1 column vectors Bn and the 2 × 2 matrices Jn recursively as follows
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Then provided α0 and β0 are sufficiently close to the coefficient values that minimize the sum of the deviations squared, then Bn converges to such coefficient values.
Proof: Now
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Thus
The proof now follows by Property 2 of Newton’s Method.


Hi Charles:
Regarding Question 1, it is standing no more. I thought it was the Fcrit, but instead it is like the p-value, then it does have the value you presented. Sorry for my confusion.
Question 2 still stands.
All the best.
Hi Charles:
I find your site very interesting and useful. Thanks for the great effort !!!
In your “Exponential Regression using Newton’s Method” page, it does not have a “Leave a Reply” at the end, so I am posting here. Sorry for any inconvenience.
Question 1. In Figure 3. Which is the formula for “Significance F”…is it “=F.INV(0.05, 1, 9)”? If that is the case, Excel gives the result of 0.00416, but you have 1.175E-06.
Question 2. Which is the rationale to have the formulas in cells Q25 and Q26, for the standard error of a and b (alfa and beta)? I mean, why you take values from the JTJ-1 matrix? Please clarify the reason.
Thanks in advance for the clarifications.
Jorge,
Question 2: This is how Newton’s Method works. See the following webpage:
https://real-statistics.com/matrices-and-iterative-procedures/newtons-method/
Charles