I am using armax model to describe the relationship between two signals. I have used matlab armax function with different model orders.
To evaluate the efficiency of the model I pulled the value from Report.Fit.FitPercent expecting that it will tell how well the model fits the experimental data. As it is fitpercent I would expect it to be between 0-100%. My results range from ~ -257 to 99.99.
I couldn't find on the mathworks or other websites how this value is calculated and how to interpret it. It would be great if you could explain how to understand the fitPercent value.
The code I used is very simple and it generates FitPercent for different model structures (orders).
opt = armaxOptions;
opt.InitialCondition = 'auto';
opt.Focus = 'simulation';
j=1; %number of dataset for analysis
i=1;
nk=0;
for na=1:1:6
for nb=1:1:6
for nc=1:1:6
m_armax = armax(data(:,:,:,j), [na nb nc nk], opt);
fit(i) = m_armax.Report.Fit.FitPercent
struct(:,i) = [na;nb;nc];
i=i+1
end
end
end