Class: Evalir::EvaliratorCollection

Inherits:
Object
  • Object
show all
Includes:
Enumerable
Defined in:
lib/evalir/evalirator_collection.rb

Instance Method Summary collapse

Constructor Details

#initialize ⇒ EvaliratorCollection

Returns a new instance of EvaliratorCollection.



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# File 'lib/evalir/evalirator_collection.rb', line 5

def initialize
  @evalirators = []
end

Instance Method Details

#<<(evalirator) ⇒ Object

Adds an evalirator to the set over which calculations are done.



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# File 'lib/evalir/evalirator_collection.rb', line 21

def <<(evalirator)
  @evalirators << evalirator
end

#add(relevant_docids, retrieved_docids) ⇒ Object

Adds a list of relevant documents, and a list of retrived documents. This rep- resents one information need.



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# File 'lib/evalir/evalirator_collection.rb', line 38

def add(relevant_docids, retrieved_docids)
  @evalirators << Evalirator.new(relevant_docids, retrieved_docids)
end

#average_ndcg_at(k, logbase = 2) ⇒ Object

Gets the average Normalized Discounted Cumulative Gain over all queries.



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# File 'lib/evalir/evalirator_collection.rb', line 74

def average_ndcg_at(k, logbase = 2)
  values = self.lazy_map {|e| e.ndcg_at(k, logbase)}
  values.reduce(0.0) { |acc, v| acc + (v / self.size) }
end

#each(&block) ⇒ Object

Calls block once for each element in self, passing that element as a parameter.



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# File 'lib/evalir/evalirator_collection.rb', line 15

def each(&block)
  @evalirators.each(&block)
end

#lazy_map(&blk) ⇒ Object

Maps over all elements, executing blk on every evalirator.



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# File 'lib/evalir/evalirator_collection.rb', line 27

def lazy_map(&blk)
  Enumerator.new do |yielder|
    self.each do |e|
      yielder << blk[e]
    end
  end
end

#mean_average_precision ⇒ Object

Mean Average Precision - this is just a fancy way of saying ‘average average precision’!



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# File 'lib/evalir/evalirator_collection.rb', line 45

def mean_average_precision
  @evalirators.reduce(0.0) {|avg,e| avg + (e.average_precision / @evalirators.size)}
end

#mean_reciprocal_rank ⇒ Object 



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# File 'lib/evalir/evalirator_collection.rb', line 49

def mean_reciprocal_rank
  self.reduce(0.0) { |avg,e| avg + (e.reciprocal_rank / self.size)}
end

#precision_recall_curve(from = 0, to = 100, step = 10) ⇒ Object

Gets the data for the precision-recall curve, ranging over the interval [from, to], with a step size of step. This is the average over all evalirators.



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# File 'lib/evalir/evalirator_collection.rb', line 57

def precision_recall_curve(from = 0, to = 100, step = 10)
  raise "From must be in the interval [0, 100)" unless (from >= 0 and from < 100)
  raise "To must be in the interval (from, 100]" unless (to > from and to <= 100)
  raise "Invalid step size - (to-from) must be divisible by step." unless ((to - from) % step) == 0
  return nil if @evalirators.empty?

  steps = ((to - from) / step) + 1
  curves = self.lazy_map { |e| e.precision_recall_curve(from, to, step) }
  curves.reduce([0] * steps) do |acc, data|
    data.each_with_index.map do |d,i|
      acc[i] += d / self.size
    end
  end
end

#size ⇒ Object 



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# File 'lib/evalir/evalirator_collection.rb', line 9

def size
  @evalirators.size
end