'run all ftests on the joint model
Returns
fres : str
a string that lists the results of all individual f-tests
summarytable : list of tuples
contains (pair, (fvalue, pvalue,df_denom, df_num)) for each f-test
Note
This are the raw results and not formatted for nice printing.'

def ftest_summary(self):

    if (not hasattr(self, 'lsjoint')):
        self.fitjoint()
    txt = []
    summarytable = []
    txt.append('F-test    for    equality    of    coefficients    across    groups')
    fres = self.lsjoint.f_test(self.contrasts['all'])
    txt.append(fres.__str__())
    summarytable.append(('all', (fres.fvalue, fres.pvalue, fres.df_denom, fres.df_num)))
    pairs = np.triu_indices(len(self.unique), 1)
    for (ind1, ind2) in zip(*pairs):
        g1 = self.unique[ind1]
        g2 = self.unique[ind2]
        txt.append(('F-test    for    equality    of    coefficients    between    group    %s    and    group    %s' % (g1, g2)))
        group = (g1, g2)
        fres = self.lsjoint.f_test(self.contrasts[group])
        txt.append(fres.__str__())
        summarytable.append((group, (fres.fvalue, fres.pvalue, fres.df_denom, fres.df_num)))
    self.summarytable = summarytable
    return ('\n'.join(txt), summarytable)
