diff --git a/src/SymptomsCausedByVaccines/MultiLineFitting/ClustersFactoryTest.py b/src/SymptomsCausedByVaccines/MultiLineFitting/ClustersFactoryTest.py
index 2f5e323f85b..64562d5faea 100644
--- a/src/SymptomsCausedByVaccines/MultiLineFitting/ClustersFactoryTest.py
+++ b/src/SymptomsCausedByVaccines/MultiLineFitting/ClustersFactoryTest.py
@@ -24,6 +24,28 @@ class ClustersFactoryTest(unittest.TestCase):
                     [0]
                 ]))
 
+    def test_createPreferenceMatrix2(self):
+        # Given
+        points = [(1, 0), (2, 0), (3, 0), (1, 1), (2, 2), (3, 3)]
+        lines = [Line.from_points([0, 0], [1, 0]), Line.from_points([0, 0], [1, 1])]
+        consensusThreshold = 0.001
+
+        # When
+        preferenceMatrix = ClustersFactory.createPreferenceMatrix(points, lines, consensusThreshold)
+
+        # Then
+        np.testing.assert_array_equal(
+            preferenceMatrix,
+            np.array(
+                [
+                    [1, 0],
+                    [1, 0],
+                    [1, 0],
+                    [0, 1],
+                    [0, 1],
+                    [0, 1]
+                ]))
+
     def test_createClusters(self):
         # Given
         preferenceMatrix = np.array(
@@ -42,3 +64,26 @@ class ClustersFactoryTest(unittest.TestCase):
                 [
                     [1, 0]
                 ]))
+
+    def test_createClusters2(self):
+        # Given
+        preferenceMatrix = np.array(
+                [
+                    [1, 1],
+                    [1, 0],
+                    [1, 0],
+                    [0, 1],
+                    [0, 1]
+                ])
+
+        # When
+        _, clusters = ClustersFactory.createClusters(preferenceMatrix)
+
+        # Then
+        np.testing.assert_array_equal(
+            clusters,
+            np.array(
+                [
+                    [2, 1, 0],
+                    [4, 3]
+                ]))