diff --git a/edu.kit.ipd.descartes.adaptation/src/edu/kit/ipd/descartes/adaptation/AdaptationControl.java b/edu.kit.ipd.descartes.adaptation/src/edu/kit/ipd/descartes/adaptation/AdaptationControl.java
index 5d954789ad3ef5c077be2753dd789d7dae2c53f9..5bb1d6c1a441e0665b708c8eccde558053e12657 100644
--- a/edu.kit.ipd.descartes.adaptation/src/edu/kit/ipd/descartes/adaptation/AdaptationControl.java
+++ b/edu.kit.ipd.descartes.adaptation/src/edu/kit/ipd/descartes/adaptation/AdaptationControl.java
@@ -178,8 +178,8 @@ public class AdaptationControl {
      */
     public void processResults(WeightedTactic tactic) {
 
-        // Impact latestImpact = perfdatarepo.getImpactAt(iteration);
-        String expName = ObservationRepositoryHelper.deriveExperimentName(tactic);
+//        Impact latestImpact = perfdatarepo.getImpactAt(iteration);
+        String expName = ObservationRepositoryHelper.deriveExperimentName(tactic, iteration + 1);
         Impact latestImpact = PerfDataRepoConverter.convertObservableImpact(ObservationRepositoryHelper
                 .searchImpactOfTactic(expName, performanceDataRepoXmiFilePath));
         // Connect parsed results to the executed tactic
@@ -207,7 +207,7 @@ public class AdaptationControl {
     }
 
     /**
-     * Graceful stop the adaptation process.
+     * Gracefully stop the adaptation process.
      */
     public void stop() {
         logger.info("Stopping adaptation process");
diff --git a/edu.kit.ipd.descartes.adaptation/src/edu/kit/ipd/descartes/adaptation/model/perfdatarepo/ObservationRepositoryHelper.java b/edu.kit.ipd.descartes.adaptation/src/edu/kit/ipd/descartes/adaptation/model/perfdatarepo/ObservationRepositoryHelper.java
index fa8785fadaa395be8ba1f7e70a3f3a0370939411..410ff945eee2b232dddceb1babca6868f9c31481 100644
--- a/edu.kit.ipd.descartes.adaptation/src/edu/kit/ipd/descartes/adaptation/model/perfdatarepo/ObservationRepositoryHelper.java
+++ b/edu.kit.ipd.descartes.adaptation/src/edu/kit/ipd/descartes/adaptation/model/perfdatarepo/ObservationRepositoryHelper.java
@@ -43,6 +43,9 @@ public class ObservationRepositoryHelper {
     }
 
     private static ObservableImpact deriveImpact(Observation o, ObservationRepository repo) {
+        if (o == null || repo == null)
+            return null;
+        
         List<ObservableImpact> impacts = repo.getImpacts();
         for (ObservableImpact oi : impacts) {
             if (EcoreUtil.equals(oi.getAfter(), o))
@@ -59,6 +62,9 @@ public class ObservationRepositoryHelper {
      * @return first result that ends the given suffix, null otherwise.
      */
     public static Observation getResultEndingWith(String suffix, ObservationRepository repo) {
+        if (suffix == null || repo == null)
+            return null;
+        
         List<Observation> results = repo.getObservations();
         for (Observation o : results) {
             if (o.getIdentifier().endsWith(suffix))