diff --git a/setup.py b/setup.py
index <HASH>..<HASH> 100644
--- a/setup.py
+++ b/setup.py
@@ -13,7 +13,7 @@ Welcome
 
 setup(
     name='synonyms',
-    version='1.9',
+    version='2.0',
     description='Chinese Synonyms for Natural Language Processing and Understanding',
     long_description=LONGDOC,
     author='Hai Liang Wang, Hu Ying Xi',
diff --git a/synonyms/__init__.py b/synonyms/__init__.py
index <HASH>..<HASH> 100755
--- a/synonyms/__init__.py
+++ b/synonyms/__init__.py
@@ -219,8 +219,8 @@ def _similarity_distance(s1, s2):
     # https://docs.scipy.org/doc/numpy-1.13.0/reference/generated/numpy.linalg.norm.html
     g = 1 / (np.linalg.norm(a - b) + 1)
     u = _levenshtein_distance(s1, s2)
-    r = g * 1.8 + u * 0.4
-    r = min((r * 18), 1.0)
+    r = g * 5 + u * 0.8
+    r = min(r, 1.0)
 
     return float("%.3f" % r)
Refine distance params, upgrade to v2