diff --git a/lib/tasks/tag_clustering.rake b/lib/tasks/tag_clustering.rake
index 402a7261d3981f2685c17a81ed85eb30858de0fb..8a7e942f40dfa8051652f96eebecb19faf7a5387 100644
--- a/lib/tasks/tag_clustering.rake
+++ b/lib/tasks/tag_clustering.rake
@@ -197,10 +197,10 @@ namespace :tag do
 
     puts "\nStarted Ranking LOs...\n"
     # ranks each LO
-    # freq = cluster_frequency(close_tags)
+    # freq_cluster = cluster_frequency(close_tags)
     LearningObject.all.each do |lo|
       los_ranked[lo.id] = relevance_frequency_rank(lo, close_tags)
-      # los_ranked[lo.id] = relevance_frequency_rank_global(lo, close_tags, freq)
+      # los_ranked[lo.id] = relevance_frequency_rank_global(lo, close_tags, freq_cluster)
       # los_ranked[lo.id] = relevance_raw_rank(lo, close_tags)
     end
 
@@ -245,7 +245,7 @@ namespace :tag do
 
   def relevance_frequency_rank_global(lo, close_tags, freq_cluster)
     # for each tag in LO that is in the cluster, accumulate it's rank
-    rank_sum = 0
+    rank_sum = 1
     lo.tags.each do |t|
       close_tags.each do |tag|
         if tag[:id] == t.id
@@ -255,11 +255,11 @@ namespace :tag do
     end
 
     wdf = 0
-    wdf = (Math.log2(freq+1)/(Math.log2(lo.tags.size)+1)) if lo.tags.size != 0
+    wdf = (Math.log2(rank_sum)/(Math.log2(lo.tags.size)+1)) if lo.tags.size != 0
 
     itf = Math.log2(Tag.all.size/freq_cluster)+1
 
-    return wdf*itf*rank_sum
+    return wdf*itf
   end
 
   # returns the rank sum of the tags in the LO