diff --git a/ComStats/comstats.py b/ComStats/comstats.py
index 5312354..1b36b04 100644
--- a/ComStats/comstats.py
+++ b/ComStats/comstats.py
@@ -16,7 +16,7 @@ def weighted_t_test_(v, weights):
weighted_count = np.nansum(weights, axis=1)
mean = np.nansum(v * weights, axis=1) / np.nansum(weights, axis=1)
t_nom = mean[:, np.newaxis] - mean
- var = np.sqrt(np.nansum(((v.T - mean)**2) * weights.T, axis=0) / np.nansum(weights, axis=1))**2
+ var = np.sqrt(np.nansum(((v.T - mean)**2) * weights.T, axis=0) / (np.nansum(weights, axis=1) - 1))
t_denom = weighted_count * var + weighted_count[:, np.newaxis] * var[:, np.newaxis]
inv_base = 1/weighted_count + 1/weighted_count[:, np.newaxis]
dof = base + base[:, np.newaxis] - 2
diff --git a/test/test_stats.py b/test/test_stats.py
index cadcd70..09e698c 100644
--- a/test/test_stats.py
+++ b/test/test_stats.py
@@ -12,10 +12,18 @@ def setUp(self):
[3, 0, 1, 3, 0, 0, 2, 1, 2, 3, 3, 1, 0, 0, 2]
])
self.weights = np.array([
- [1, 0.1, 0.2, 0.3, 2, 0.1, 0.1, 2, 0.1, 0.1, 0.2, 0.1, 0.3, 0.4, 1],
- [1, 0.1, 0.2, 0.3, 2, 0.1, 0.1, 2, 0.1, 0.1, 0.2, 0.1, 0.3, 0.4, 1],
- [1, 0.1, 0.2, 0.3, 2, 0.1, 0.1, 2, 0.1, 0.1, 0.2, 0.1, 0.3, 0.4, 1],
- [1, 0.1, 0.2, 0.3, 2, 0.1, 0.1, 2, 0.1, 0.1, 0.2, 0.1, 0.3, 0.4, 1]
+ [1.875000, 0.187500, 0.375000, 0.562500, 3.750000, 0.187500,
+ 0.187500, 3.750000, 0.187500, 0.187500, 0.375000, 0.187500,
+ 0.562500, 0.750000, 1.875000],
+ [1.875000, 0.187500, 0.375000, 0.562500, 3.750000, 0.187500,
+ 0.187500, 3.750000, 0.187500, 0.187500, 0.375000, 0.187500,
+ 0.562500, 0.750000, 1.875000],
+ [1.875000, 0.187500, 0.375000, 0.562500, 3.750000, 0.187500,
+ 0.187500, 3.750000, 0.187500, 0.187500, 0.375000, 0.187500,
+ 0.562500, 0.750000, 1.875000],
+ [1.875000, 0.187500, 0.375000, 0.562500, 3.750000, 0.187500,
+ 0.187500, 3.750000, 0.187500, 0.187500, 0.375000, 0.187500,
+ 0.562500, 0.750000, 1.875000]
])
self.percentage_input_set = np.array([
[0.1, 0.05, 0.05, 0.1, 0.6, 0.0, 0.4, 0.1, 0.1, 0.05, 0.1, 0.0, 0.0, 0.0, 0.1],
@@ -98,27 +106,27 @@ def test_unweighted_t_test_equal_variance_one_sided(self):
self.assertTrue((scores.round(8) == expected_scores).all())
def test_weighted_t_test(self):
- expected_p_values = [[ 1.00000000e+00, 1.42077000e-03, 5.10308380e-01, 7.37402900e-02],
- [ 1.42077000e-03, 1.00000000e+00, 6.57160000e-04, 8.87667500e-02],
- [ 5.10308380e-01, 6.57160000e-04, 1.00000000e+00, 3.35990600e-02],
- [ 7.37402900e-02, 8.87667500e-02, 3.35990600e-02, 1.00000000e+00]]
- expected_scores = [[ 0. , -3.53992642, 0.66687841, -1.85781692],
- [ 3.53992642, 0. , 3.83253879, 1.76327075],
- [-0.66687841, -3.83253879, 0. , -2.23466985],
- [ 1.85781692, -1.76327075, 2.23466985, 0. ]]
+ expected_p_values = [[ 1.0000000e+00, 5.4909000e-04, 6.4793643e-01, 8.8074170e-02],
+ [ 5.4909000e-04, 1.0000000e+00, 2.3130000e-04, 5.4144420e-02],
+ [ 6.4793643e-01, 2.3130000e-04, 1.0000000e+00, 4.2462860e-02],
+ [ 8.8074170e-02, 5.4144420e-02, 4.2462860e-02, 1.0000000e+00]]
+ expected_scores = [[ 0. , -3.89999446, 0.46159717, -1.76731592],
+ [ 3.89999446, 0. , 4.22167128, 2.01009271],
+ [ -0.46159717, -4.22167128, 0. , -2.12593206],
+ [ 1.76731592, -2.01009271, 2.12593206, 0. ]]
p_values, scores = comstats.t_test(self.input_set, self.weights, {'paired': False, 'equal_variance': False})
self.assertTrue((p_values.round(8) == expected_p_values).all())
self.assertTrue((scores.round(8) == expected_scores).all())
def test_weighted_t_test_one_sided(self):
- expected_p_values = [[ 5.00000000e-01, 7.10380000e-04, 2.55154190e-01, 3.68701500e-02],
- [ 7.10380000e-04, 5.00000000e-01, 3.28580000e-04, 4.43833800e-02],
- [ 2.55154190e-01, 3.28580000e-04, 5.00000000e-01, 1.67995300e-02],
- [ 3.68701500e-02, 4.43833800e-02, 1.67995300e-02, 5.00000000e-01]]
- expected_scores = [[ 0. , -3.53992642, 0.66687841, -1.85781692],
- [ 3.53992642, 0. , 3.83253879, 1.76327075],
- [-0.66687841, -3.83253879, 0. , -2.23466985],
- [ 1.85781692, -1.76327075, 2.23466985, 0. ]]
+ expected_p_values = [[ 5.0000000e-01, 2.7454000e-04, 3.2396821e-01, 4.4037080e-02],
+ [ 2.7454000e-04, 5.0000000e-01, 1.1565000e-04, 2.7072210e-02],
+ [ 3.2396821e-01, 1.1565000e-04, 5.0000000e-01, 2.1231430e-02],
+ [ 4.4037080e-02, 2.7072210e-02, 2.1231430e-02, 5.0000000e-01]]
+ expected_scores = [[ 0. , -3.89999446, 0.46159717, -1.76731592],
+ [ 3.89999446, 0. , 4.22167128, 2.01009271],
+ [ -0.46159717, -4.22167128, 0. , -2.12593206],
+ [ 1.76731592, -2.01009271, 2.12593206, 0. ]]
p_values, scores = comstats.t_test(self.input_set, self.weights, {'paired': False, 'equal_variance': False}, True)
self.assertTrue((p_values.round(8) == expected_p_values).all())
self.assertTrue((scores.round(8) == expected_scores).all())