diff --git a/PHPSkills/FactorGraphs/Factor.php b/PHPSkills/FactorGraphs/Factor.php
index a3a911a..cf7e2d3 100644
--- a/PHPSkills/FactorGraphs/Factor.php
+++ b/PHPSkills/FactorGraphs/Factor.php
@@ -1,13 +1,13 @@
 <?php
 namespace Moserware\Skills\FactorGraphs;
 
-require_once(dirname(__FILE__) . "../Guard.php");
-require_once(dirname(__FILE__) . "../HashMap.php");
+require_once(dirname(__FILE__) . "./../Guard.php");
+require_once(dirname(__FILE__) . "./../HashMap.php");
 
 use Moserware\Skills\Guard;
 use Moserware\Skills\HashMap;
 
-class Factor
+abstract class Factor
 {
     private $_messages = array();
     private $_messageToVariableBinding;
@@ -78,11 +78,11 @@ class Factor
 
     public abstract function createVariableToMessageBinding($variable);
 
-    protected function createVariableToMessageBinding($variable, $message)
+    protected function createVariableToMessageBindingWithMessage($variable, $message)
     {
         $index = count($this->_messages);
         $this->_messages[] = $message;
-        $this->_messageToVariableBinding->setValue($message) = $variable;
+        $this->_messageToVariableBinding->setValue($message, $variable);
         $this->_variables[] = $variable;
         return $message;
     }
diff --git a/PHPSkills/FactorGraphs/FactorList.php b/PHPSkills/FactorGraphs/FactorList.php
index 97d9d99..bc6db9a 100644
--- a/PHPSkills/FactorGraphs/FactorList.php
+++ b/PHPSkills/FactorGraphs/FactorList.php
@@ -2,7 +2,7 @@
 
 namespace Moserware\Skills\FactorGraphs;
 
-require_once(dirname(__FILE__) . "Factor.php");
+require_once(dirname(__FILE__) . "./Factor.php");
 
 /// <summary>
 /// Helper class for computing the factor graph's normalization constant.
diff --git a/PHPSkills/FactorGraphs/Schedule.php b/PHPSkills/FactorGraphs/Schedule.php
index 0c432ab..4ac941a 100644
--- a/PHPSkills/FactorGraphs/Schedule.php
+++ b/PHPSkills/FactorGraphs/Schedule.php
@@ -30,7 +30,7 @@ class ScheduleStep extends Schedule
         $this->_index = $index;
     }
 
-    public function visit($depth, $maxDepth)
+    public function visit($depth = -1, $maxDepth = 0)
     {
         $delta = $this->_factor->updateMessageIndex($this->_index);
         return $delta;
@@ -47,7 +47,7 @@ class ScheduleSequence extends Schedule
         $this->_schedules = $schedules;
     }
 
-    public function visit($depth, $maxDepth)
+    public function visit($depth = -1, $maxDepth = 0)
     {
         $maxDelta = 0;
 
@@ -72,7 +72,7 @@ class ScheduleLoop extends Schedule
         $this->_maxDelta = $maxDelta;
     }
 
-    public function visit($depth, $maxDepth)
+    public function visit($depth = -1, $maxDepth = 0)
     {
         $totalIterations = 1;
         $delta = $this->_scheduleToLoop->visit($depth + 1, $maxDepth);
diff --git a/PHPSkills/TrueSkill/TrueSkillFactorGraph.php b/PHPSkills/TrueSkill/TrueSkillFactorGraph.php
index 9ceed88..cbd294d 100644
--- a/PHPSkills/TrueSkill/TrueSkillFactorGraph.php
+++ b/PHPSkills/TrueSkill/TrueSkillFactorGraph.php
@@ -1,11 +1,11 @@
 <?php
 namespace Moserware\Skills\TrueSkill;
 
-require_once(dirname(__FILE__) . '../Rating.php');
-require_once(dirname(__FILE__) . '../FactorGraphs/FactorList.php');
-require_once(dirname(__FILE__) . '../FactorGraphs/Schedule.php');
-require_once(dirname(__FILE__) . '../FactorGraphs/VariableFactory.php');
-require_once(dirname(__FILE__) . '../Numerics/GaussianDistribution.php');
+require_once(dirname(__FILE__) . './../Rating.php');
+require_once(dirname(__FILE__) . './../FactorGraphs/FactorList.php');
+require_once(dirname(__FILE__) . './../FactorGraphs/Schedule.php');
+require_once(dirname(__FILE__) . './../FactorGraphs/VariableFactory.php');
+require_once(dirname(__FILE__) . './../Numerics/GaussianDistribution.php');
 require_once(dirname(__FILE__) . '/Layers/PlayerPriorValuesToSkillsLayer.php');
 require_once(dirname(__FILE__) . '/Layers/PlayerSkillsToPerformancesLayer.php');
 require_once(dirname(__FILE__) . '/Layers/IteratedTeamDifferencesInnerLayer.php');
diff --git a/UnitTests/TrueSkill/FactorGraphTeamTrueSkillCalculatorTest.php b/UnitTests/TrueSkill/FactorGraphTeamTrueSkillCalculatorTest.php
new file mode 100644
index 0000000..708fb5f
--- /dev/null
+++ b/UnitTests/TrueSkill/FactorGraphTeamTrueSkillCalculatorTest.php
@@ -0,0 +1,27 @@
+<?php
+require_once 'PHPUnit/Framework.php';
+require_once 'PHPUnit/TextUI/TestRunner.php';
+
+require_once(dirname(__FILE__) . '/../../PHPSkills/TrueSkill/FactorGraphTrueSkillCalculator.php');
+require_once(dirname(__FILE__) . '/TrueSkillCalculatorTests.php');
+
+use \PHPUnit_Framework_TestCase;
+use Moserware\Skills\TrueSkill\FactorGraphTrueSkillCalculator;
+
+class FactorGraphTrueSkillCalculatorTest extends PHPUnit_Framework_TestCase
+{
+    public function testFactorGraphTrueSkillCalculator()
+    {
+        $calculator = new FactorGraphTrueSkillCalculator();
+
+        // We only support two players
+        TrueSkillCalculatorTests::testAllTwoPlayerScenarios($this, $calculator);
+        TrueSkillCalculatorTests::testAllTwoTeamScenarios($this, $calculator);
+    }
+}
+
+$testSuite = new \PHPUnit_Framework_TestSuite();
+$testSuite->addTest( new TwoTeamTrueSkillCalculatorTest("testFactorGraphTrueSkillCalculator"));
+
+\PHPUnit_TextUI_TestRunner::run($testSuite);
+?>