MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi

Learn moreOpportunities for recent engineering grads.

Apply Today**New to MATLAB?**

Asked by seongwoo oh
on 18 Nov 2012

Hello

I have a set of x and y values that i want to plot the logistic regression of.

I was looking at glmft built in function but it seems to take more than inputs x and y

All i wanna do is to come up with logistic fit of the given x and y values on x y plane.

Any thoughts?

(I do have cf toolbox but the program needs to be self contained and i m looking for a built in function or a code that spits out coefficients for logistic model)

*No products are associated with this question.*

Answer by Tom Lane
on 19 Nov 2012

Here's a way to fit a logistic curve to continuous data using Curve Fitting:

>> x = rand(100,1); >> y = 1./(1+exp(-3*(x-.5))) + randn(size(x))/100; >> fit(x,y,'1./(1+exp(b1+b2*x))','start',[ -1 1]) ans = General model: ans(x) = 1./(1+exp(b1+b2*x)) Coefficients (with 95% confidence bounds): b1 = 1.517 (1.494, 1.54) b2 = -3.037 (-3.079, -2.996)

Lalit Patil
on 15 Dec 2012

Sir, i seen your answer, and i have done the same thing at below link using SVD.. Here i am getting four coefficients..

http://www.mathworks.in/matlabcentral/answers/54780-how-to-do-svd-without-function

So, can i do the same thing with your method to find the coefficients..?

## 0 Comments