def edf_mtotdev(N, m, alpha):
    """ Equivalent degrees of freedom for Modified Total Deviation

        NIST SP1065 page 41, Table 8
    """
    assert alpha in [2, 1, 0, -1, -2]
    NIST_SP1065_table8 = [(1.9, 2.1), (1.2, 1.4), (1.1, 1.2), (0.85, 0.5),
        (0.75, 0.31)]
    b, c = NIST_SP1065_table8[abs(alpha - 2)]
    edf = b * (float(N) / float(m)) - c
    print('mtotdev b,c= ', (b, c), ' edf=', edf)
    return edf
