statisticalAnalysis.m

function [resp] = statisticalAnalysis(gpaGroup1, gpaGroup2, dispOpt)
    % applies statistical test on group1 and group2 in order to determine 
    % if they come from the same distribution. If data is normal then ANOVA is used, 
    % if not then some other test.
    %
    % input: gpaGroup1, gpaGroup2 = vectors or rows of numbers
    %        dispOpt = 'on' or 'off' - plot BoxPlot of Anova (or other test)
    % return: 0 - data comes from the same distribution
    %         1 - data comes from different distribution
    resp = 0;

    if nargin<3
      dispOpt='off';
    end 

    if isrow(gpaGroup1)
        gpaGroup1 = gpaGroup1';
    end
    if isrow(gpaGroup2)
        gpaGroup2 = gpaGroup2';
    end

    g1normal = checkNormality(gpaGroup1, 2);
    g2normal = checkNormality(gpaGroup2, 2);

    data = [gpaGroup1 gpaGroup2];

    if g1normal==1 && g2normal == 1
        [P,ANOVATAB,STATS] = anova1(data,[], dispOpt); 
        if(P<0.05) 
            alpha = num2str(P);
            df1 = num2str(cell2mat(ANOVATAB(2,3)));
            df2 = num2str(cell2mat(ANOVATAB(3,3)));
            F = num2str(cell2mat(ANOVATAB(2,5)));
            disp(['[ANOVA]: distributions are different with F(alpha,d1,d2) = F(',alpha,',',df1,',',df2,')=',F]);
            resp = 1;
        end
    else
        [P,ANOVATAB,STATS] = kruskalwallis(data,[],  dispOpt); 
        if(P<0.05) 
            alpha = num2str(P);
            df1 = num2str(cell2mat(ANOVATAB(2,3)));
            df2 = num2str(cell2mat(ANOVATAB(3,3)));
            F = num2str(cell2mat(ANOVATAB(2,5)));
            disp(['[kruskalwallis]: distributions are different with F(alpha,d1,d2) = F(',alpha,',',df1,',',df2,')=',F]);
            resp = 1;
        end
    end

    if(resp==0)
        disp('Distributions of grades before and after are the same :( !') 
    end
end