diff --git a/prism/src/explicit/MDP.java b/prism/src/explicit/MDP.java
index 6d5153fe..d849dc43 100644
--- a/prism/src/explicit/MDP.java
+++ b/prism/src/explicit/MDP.java
@@ -45,11 +45,14 @@ public class MDP extends Model
 	protected List<List<Distribution>> trans;
 
 	// Action labels
+	// (null in element s means no actions for that state)
 	protected List<List<Object>> actions;
 
 	// Rewards
-	protected List<List<Double>> transRewards;
+	// (if transRewardsConstant non-null, use this for all transitions; otherwise, use transRewards list)
+	// (for transRewards, null in element s means no rewards for that state)
 	protected Double transRewardsConstant;
+	protected List<List<Double>> transRewards;
 
 	// Flag: allow duplicates in distribution sets?
 	protected boolean allowDupes = false;
diff --git a/prism/src/explicit/MDPModelChecker.java b/prism/src/explicit/MDPModelChecker.java
index e6f3ba8d..66452d73 100644
--- a/prism/src/explicit/MDPModelChecker.java
+++ b/prism/src/explicit/MDPModelChecker.java
@@ -457,10 +457,6 @@ public class MDPModelChecker extends ModelChecker
 		// Start iterations
 		iters = 0;
 		while (iters < k) {
-
-			// Print vector (for debugging)
-			mainLog.println(soln);
-
 			iters++;
 			// Matrix-vector multiply and min/max ops
 			mdp.mvMultMinMax(soln, min, soln2, target, true);