diff --git a/src/main/java/org/oreland/analysis/Analysis.java b/src/main/java/org/oreland/analysis/Analysis.java
index 139fb08..1449b06 100644
--- a/src/main/java/org/oreland/analysis/Analysis.java
+++ b/src/main/java/org/oreland/analysis/Analysis.java
@@ -6,6 +6,8 @@
 import org.oreland.entity.Player;
 import org.apache.commons.math3.stat.descriptive.SummaryStatistics;
 
+import java.util.Date;
+import java.util.HashMap;
 import java.util.Iterator;
 
 /**
@@ -16,7 +18,12 @@ public class Analysis {
     Repository repo;
 
     public Analysis(Repository repo) {
-        this.repo = repo;
+        this.repo = repo.clone();
+        mergeSplitActivities();
+    }
+
+    private void mergeSplitActivities() {
+        HashMap<Date, Activity> activities = new HashMap<>();
     }
 
     public void report() {
diff --git a/src/main/java/org/oreland/db/Repository.java b/src/main/java/org/oreland/db/Repository.java
index ba5eeff..d564072 100644
--- a/src/main/java/org/oreland/db/Repository.java
+++ b/src/main/java/org/oreland/db/Repository.java
@@ -19,6 +19,32 @@ public class Repository {
     HashMap<String, Player> playersByName = new HashMap<>();
     List<Level> levels = new ArrayList<>();
 
+    // "Deep copy"
+    public Repository clone() {
+        Repository rep = new Repository();
+        for (Player p : playersByName.values()) {
+            rep.add(p.copy());  // shallow copy
+        }
+        for (Activity a : activities.values()) {
+            Activity new_a = a.copy();  // shallow copy
+            rep.add(new_a);
+            for (Activity.Invitation inv : a.invitations) {
+                Activity.Invitation new_inv = new Activity.Invitation();
+                new_inv.invitation_date = inv.invitation_date;
+                new_inv.player = rep.getPlayer(inv.player.first_name, inv.player.last_name);
+                new_inv.response = inv.response;
+                new_inv.response_comment = inv.response_comment;
+                new_inv.response_date = inv.response_date;
+                rep.addInvitation(new_a, new_inv);
+            }
+            for (Activity.Participant par : a.participants) {
+                Activity.Participant new_par = new Activity.Participant();
+                rep.addParticipant(new_a, rep.getPlayer(par.player.first_name, par.player.last_name));
+            }
+        }
+        return rep;
+    }
+
     public Iterable<Level> getLevels() {
         return levels;
     }
@@ -42,8 +68,6 @@ public Pair(T t, U u) {
         public U second;
     }
 
-    ;
-
     public Player add(Player p) {
         String key = p.first_name + p.last_name;
         if (!playersByName.containsKey(key))
diff --git a/src/main/java/org/oreland/entity/Activity.java b/src/main/java/org/oreland/entity/Activity.java
index c1446fe..6b4e67c 100644
--- a/src/main/java/org/oreland/entity/Activity.java
+++ b/src/main/java/org/oreland/entity/Activity.java
@@ -10,6 +10,18 @@
  */
 public class Activity {
 
+    public Activity copy() {
+        Activity a = new Activity();
+        a.id = id;
+        a.type = type;
+        a.date = date;
+        a.title = title;
+        a.description = description;
+        a.synced = synced;
+        a.level = level;
+        return a;
+    }
+
     public enum Type {
         GAME,
         TRAINING;
diff --git a/src/main/java/org/oreland/entity/Player.java b/src/main/java/org/oreland/entity/Player.java
index 36a644c..f24be3d 100644
--- a/src/main/java/org/oreland/entity/Player.java
+++ b/src/main/java/org/oreland/entity/Player.java
@@ -8,13 +8,23 @@
  * Created by jonas on 10/1/15.
  */
 public class Player {
+
+
+    public Player copy() {
+        Player p = new Player();
+        p.first_name = first_name;
+        p.last_name = last_name;
+        p.type = type;
+        p.level_history.addAll(level_history);
+        p.target_level = target_level;
+        return p;
+    }
+
     static public class LevelHistoryEntry {
         public Date date;
         public TargetLevel level;
     }
 
-    ;
-
     public enum Type {
         PLAYER,
         LEADER;