MATLAB: Gaussian psychometric curve fit

erfcgaussian

I have x = 1:5; y = [0.97 0.89 0.5 0.08 0.03]; how to find bias and slope using the function

Best Answer

Use the mldivide,\ function:

x = 1:5; 
y = [0.97 0.89 0.5 0.08 0.03];
P = [ones(size(x(:)))  x(:)]\y(:);
Bias = P(1)
Slope = P(2)
Bias =
    1.3010
Slope =
   -0.2690

Related Solutions

MATLAB: Gaussian psychometric curve fit to the data

This works:

x = 1:5; 
y = [0.97 0.89 0.5 0.08 0.03];
f = @(p,x) 1/2 * erfc ( (x - p(1)) ./ (p(2).*sqrt(2)) );
P = fminsearch(@(p) norm(y - f(p,x)), [1; 1]);
Bias = P(1)
Slope = P(2)
Bias =
    2.9815
Slope =
    0.7784

MATLAB: Skill with regexprep

This should get you started:

>> str = '5*0.02 0.02 0.04 0.08 0.15 0.3 0.5 1 2 3 30*5 30*10 30*20 30*40 30*60';
>> fun = @(n,c)repmat(sprintf(' %s',c),1,str2double(n)); % or JOIN rather than SPRINTF.
>> str = regexprep(str,'\s*(\d+)\*(\S+)','${fun($1,$2)}')
str =
 0.02 0.02 0.02 0.02 0.02 0.02 0.04 0.08 0.15 0.3 0.5 1 2 3 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60

https://www.mathworks.com/help/matlab/matlab_prog/dynamic-regular-expressions.html

If you use join then you can get rid of the leading \s*.

Best Answer

Related Solutions

MATLAB: Gaussian psychometric curve fit to the data

MATLAB: Skill with regexprep

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