MATLAB: Extract model’s p-value from fitnlm

Question

Dear all,

I am using the Statistical Toolbox (Matlab2013b) to perform a regression analysis. Using apply different regression functions to my dataset (linear,quadratic,exponential) using "fitnlm". I want to choose the best function based on R^2 and p-value. The R^2 is found in the model's output fields. The overall p-value I can't find though it is displayed in the command window: Nonlinear regression model, e.g.:

    y ~ b1*x1^2 + b2*x1 + b3
Estimated Coefficients:
          Estimate    SE          tStat       pValue  
    b1     0.02495    0.010583      2.3575    0.027708
    b2    -0.75062      1.0529    -0.71294     0.48337
    b3      14.633      24.854     0.58877     0.56201

Number of observations: 25, Error degrees of freedom: 22 Root Mean Squared Error: 8.27 R-Squared: 0.897, Adjusted R-Squared 0.887 F-statistic vs. constant model: 95.5, p-value = 1.43e-11

My tool should extract the model p-value = 1.43e-11 automatically (not the individual coefficients' pValue in the table). How can I do this?

Thanks!

Answer 1

In 2016a, this information is accessible via: mdl.Coefficients.pValue (assuming that mdl is the structure returned by fitnlm).