code: def test_mvn_mvt_3(self):
      a, b = self.a, self.b
      df = self.df
      corr2 = self.corr2
  
      a2 = a.copy()
      a2[:] = -np.inf
      # using higher precision in R, error approx. 6.866163e-07
      probmvn_R = 0.9961141
      # using higher precision in R, error approx. 1.6e-07
      probmvt_R = 0.9522146
      quadkwds = {"epsabs": 1e-08}
      probmvt = mvstdtprob(a2, b, corr2, df, quadkwds=quadkwds)
      assert_allclose(probmvt_R, probmvt, atol=5e-4)
      probmvn = mvstdnormcdf(a2, b, corr2, maxpts=100000, abseps=1e-5)
      assert_allclose(probmvn_R, probmvn, atol=1e-4)
  
file_path: statsmodels/statsmodels/sandbox/distributions/tests/test_multivariate.py
imports: import numpy
  from numpy.testing import assert_almost_equal, assert_allclose
  from statsmodels.sandbox.distributions.multivariate import mvstdtprob, mvstdnormcdf
  from statsmodels.sandbox.distributions.mv_normal import MVT, MVNormal
label_desc: Use image node_id 4 for calling the Test_MVN_MVT_prob obj's underlying member method code with example usage: obj.test_mvn_mvt_3() without return types