Chi-square distribution plot

Hi All,

I want to plot the chi square distribution which I have computed. I have the below code which returns me the parameters but am unable to plot the distribution.

[h,p,st]= chi2gof(Id,'NBins',nBins,'Alpha',0.05)

h =

       0

p =

      0.2530

st = 

      chi2stat: 129.9011
            df: 120
         edges: [1x124 double]
             O: [1x123 double]
             E: [1x123 double]

Id is 1x2000 vector. nBins for me ~278. Please let me know how to plot the distribution. Thanks a lot!!

Answer 1

[dpb]

Because chi2gof returns bin edges, need to convert to centers --

x=filter([0.5 0.5],1,st.edges); x=x(2:end);  % average successive edges for centers
bar(x,[st.O;st.E]','grouped')                % put the two groups together for bar
legend('Observed','Expected')                % tell who's who...