def call
      probability = 1.0

      graders.each do |lambda|
        instance = lambda.call(description)
        probability *= instance.call.to_f ** instance.weight
      end

      probability
    end
def call
      probability = 1.0

      graders.each do |lambda|
        instance = lambda.call(description)
        probability *= instance.call.to_f ** instance.weight
      end

      probability
    end
For given description, computes probabilities returned by each graders by multipying them together.

 @return [Float] the probability for the given description to be considered good