Zero reputations result in a non zero reputation when sum

[thebravoman]

Definition is:

has_reputation :popularity,
    :source => [
      {:reputation => :watched_pointsd},
      {:reputation => :views},
      {:reputation => :payment_reputation, :weight => 2}
    ],
    :aggregated_by => :sum

  has_reputation :payment_reputation,
    :source => :episode,
    :source_of => [{:reputation=>:popularity}]

  has_reputation :views,
    :source=>:user,
    :source_of => [{:reputation=>:popularity}]

	has_reputation :watched_points,
		:source=>:user,
    :source_of => [{:reputation=>:popularity}]

Then for a given episode I have

def pop e 
 puts "Popularity: #{e.reputation_for(:popularity)}" 
 puts "Watched points: #{e.reputation_for(:watched_points)}"
 puts "Views: #{e.reputation_for(:views)}"
 puts "Payment: #{e.reputation_for(:payment_reputation)}"
end

The result for a given episode is:
Popularity: -272.2
Watched points: 0.0
Views: 0.0
Payment: 0.0

How could that be? Where could I even start debugging it?