def participant_info(participant_id)
      participant_array = []
      experiments.values.sort_by(&:name).each do |e|
        index = connection.ab_assigned(e.id, participant_id)
        if index
          participant_array << [e, e.alternatives[index.to_i]]
        end
      end
      participant_array
    end
def participant_info(participant_id)
      participant_array = []
      experiments.values.sort_by(&:name).each do |e|
        index = connection.ab_assigned(e.id, participant_id)
        if index
          participant_array << [e, e.alternatives[index.to_i]]
        end
      end
      participant_array
    end
-- Participant Information --
 Returns an array of all experiments this participant is involved in, with their assignment.
  This is done as an array of arrays [[<experiment_1>, <assignment_1>], [<experiment_2>, <assignment_2>]], sorted by experiment name, so that it will give a consistent string
  when converted to_s (so could be used for caching, for example)