public void checkOutput(IOContainer output) throws MissingIOObjectException {

    if (similarity.equals("Tree")) {
      TreeDistance treedistance = output.get(TreeDistance.class);
      for (int i = 0; i < expectedValues.length; i++) {
        assertEquals(treedistance.similarity(first[i], second[i]), expectedValues[i]);
      }
    }
    if (similarity.equals("Euclidean")) {
      EuclideanDistance euclideandistance = output.get(EuclideanDistance.class);
      for (int i = 0; i < expectedValues.length; i++) {
        assertEquals(euclideandistance.similarity(first[i], second[i]), expectedValues[i]);
      }
    }
    if (similarity.equals("Comparator")) {
      PerformanceVector performancevector = output.get(PerformanceVector.class);
      assertEquals(
          expectedValues[0], performancevector.getCriterion("similarity").getAverage(), 0.00001);
    }
  }