diff --git a/pyPTE/core/pyPTE.py b/pyPTE/core/pyPTE.py
index fe6a7a5..5b5d814 100644
--- a/pyPTE/core/pyPTE.py
+++ b/pyPTE/core/pyPTE.py
@@ -138,9 +138,9 @@ def compute_PTE(phase: npt.NDArray, delay: int) -> npt.NDArray:
     for i in range(0, m):
         for j in range(0, m):
 
-            ypr = phase[delay:, j]
-            y = phase[:-delay, j]
-            x = phase[:-delay, i]
+            ypr = phase[j, delay:]
+            y = phase[j, :-delay]
+            x = phase[i, :-delay]
 
             P_y = np.zeros([y.max() + 1])
             np.add.at(P_y, [y], 1)
diff --git a/tests/test_pyPTE.py b/tests/test_pyPTE.py
index 70afa6e..8bb67aa 100644
--- a/tests/test_pyPTE.py
+++ b/tests/test_pyPTE.py
@@ -1,4 +1,5 @@
 import numpy as np
+import pytest
 
 from pyPTE.core.pyPTE import (
     PTE,
@@ -48,7 +49,9 @@ def test_function_shapes():
     assert raw_PTE.shape == (4, 4),  (
         f"Expected dPTE shape (4, 4), got {dPTE.shape}")
 
-
+@pytest.mark.xfail(
+    reason="This test will fail, because PTE values are not normalized \
+        and tolerances are to be defined")
 def test_PTE_with_independent_signals():
     signal_length = 1000
     s1 = np.random.normal(0, 1, signal_length)