mruby-changefinderを試すよ

cf.rb

cf = ChangeFinder.new(5, 0.01, 10, 0.01, 5)

File.open('result.tsv', 'w') do |f|
  File.open('go.tsv').each do |line|
    date, trend = line.chomp.split("\t")
    score = cf.score(trend.to_f)
    f.puts("#{date}\t#{trend}\t#{score}")
  end
end

description.md

結果: https://docs.google.com/spreadsheets/d/1sRJJ03rJvmt50ujepZii3YCwZIkkzsxitMMbAn0flKg/edit?usp=sharing

• mruby-changefinder https://github.com/matsumoto-r/mruby-changefinder
• 異常検知でGo！ http://qiita.com/chobie@github/items/50104014db4a0f91ed59