30 lines
903 B
Ruby
30 lines
903 B
Ruby
require 'statistics2'
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module Reports
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class UserPromotions
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def self.confidence_interval_for(user, n)
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up_votes = Post.where("created_at >= ?", min_time).where(:uploader_id => user.id).where("fav_count >= ?", n).count
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total_votes = Post.where("created_at >= ?", min_time).where(:uploader_id => user.id).count
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ci_lower_bound(up_votes, total_votes, 0.95)
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end
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def self.ci_lower_bound(pos, n, confidence)
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if n == 0
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return 0
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end
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z = Statistics2.pnormaldist(1-(1-confidence)/2)
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phat = 1.0*pos/n
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100 * (phat + z*z/(2*n) - z * Math.sqrt((phat*(1-phat)+z*z/(4*n))/n))/(1+z*z/n)
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end
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def self.min_time
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30.days.ago
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end
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def users
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User.joins(:posts).where("users.level < ?", User::Levels::CONTRIBUTOR).where("posts.created_at >= ? and posts.fav_count >= 1", self.class.min_time).order("users.name")
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end
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end
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end
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