diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,30 @@
+Copyright (c)2011, Grzegorz Chrupala
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of Grzegorz Chrupala nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/NLP/Scores.hs b/NLP/Scores.hs
new file mode 100644
--- /dev/null
+++ b/NLP/Scores.hs
@@ -0,0 +1,54 @@
+{-# LANGUAGE BangPatterns #-}
+module NLP.Scores 
+    ( 
+      sum
+    , mean
+    , accuracy
+    , recipRank
+    , avgPrecision
+    )
+where
+import Data.List hiding (sum)
+import qualified Data.Set as Set
+import Prelude hiding (sum)
+
+-- | The sum of a list of numbers (without overflowing stack, 
+-- unlike 'Prelude.sum').
+sum :: (Num a) => [a] -> a
+sum = foldl' (+) 0
+
+-- | The mean of a list of numbers.
+mean :: (Fractional n, Real a) => [a] -> n
+mean xs = 
+    let (sum,len) = foldl' (\(!s,!l) x -> (s+x,l+1)) (0,0) xs
+    in realToFrac sum/len
+
+-- | Accuracy: the proportion of elements in the first list equal to 
+-- elements at corresponding positions in second list. Lists should be
+-- of equal lengths.
+accuracy :: (Eq a, Fractional n) => [a] -> [a] -> n
+accuracy xs = mean . map fromEnum . zipWith (==) xs
+ 
+-- | Reciprocal rank: the reciprocal of the rank at which the first arguments
+-- occurs in the list given as the second argument.
+recipRank :: (Eq a, Fractional n) => a -> [a] -> n
+recipRank y ys = 
+    case [ r | (r,y') <- zip [1..] ys , y' == y ] of
+      []  -> 0
+      r:_ -> 1/fromIntegral r
+
+-- | Average precision. 
+-- <http://en.wikipedia.org/wiki/Information_retrieval#Average_precision>
+avgPrecision :: (Fractional n, Ord a) => Set.Set a -> [a] -> n
+avgPrecision gold _ | Set.size gold == 0 = 0
+avgPrecision gold xs =
+      (/fromIntegral (Set.size gold))
+    . sum 
+    . map (\(r,rel,cum) -> if rel == 0 
+                          then 0 
+                          else fromIntegral cum / fromIntegral r)
+    . takeWhile (\(_,_,cum) -> cum <= Set.size gold) 
+    . snd 
+    . mapAccumL (\z (r,rel) -> (z+rel,(r,rel,z+rel))) 0
+    $ [ (r,fromEnum $ x `Set.member` gold) | (x,r) <- zip xs [1..]]
+
diff --git a/Setup.hs b/Setup.hs
new file mode 100644
--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/nlp-scores.cabal b/nlp-scores.cabal
new file mode 100644
--- /dev/null
+++ b/nlp-scores.cabal
@@ -0,0 +1,61 @@
+-- nlp-scores.cabal auto-generated by cabal init. For additional
+-- options, see
+-- http://www.haskell.org/cabal/release/cabal-latest/doc/users-guide/authors.html#pkg-descr.
+-- The name of the package.
+Name:                nlp-scores
+
+-- The package version. See the Haskell package versioning policy
+-- (http://www.haskell.org/haskellwiki/Package_versioning_policy) for
+-- standards guiding when and how versions should be incremented.
+Version:             0.1.0
+
+-- A short (one-line) description of the package.
+Synopsis:            Scoring functions commonly used for evaluation in NLP and IR
+
+-- A longer description of the package.
+Description:   Scoring functions commonly used for evaluation in NLP and IR      
+
+-- URL for the project homepage or repository.
+Homepage:            https://bitbucket.org/gchrupala/lingo
+
+-- The license under which the package is released.
+License:             BSD3
+
+-- The file containing the license text.
+License-file:        LICENSE
+
+-- The package author(s).
+Author:              Grzegorz Chrupala
+
+-- An email address to which users can send suggestions, bug reports,
+-- and patches.
+Maintainer:          gchrupala@lsv.uni-saarland.de
+
+-- A copyright notice.
+-- Copyright:           
+
+Category:            NLP
+
+Build-type:          Simple
+
+-- Extra files to be distributed with the package, such as examples or
+-- a README.
+-- Extra-source-files:  
+
+-- Constraint on the version of Cabal needed to build this package.
+Cabal-version:       >=1.2
+
+
+Library
+  -- Modules exported by the library.
+  Exposed-modules:     NLP.Scores
+  
+  -- Packages needed in order to build this package.
+  Build-depends:  base >= 3 && < 5 ,  containers >= 0.4 
+  
+  -- Modules not exported by this package.
+  -- Other-modules:       
+  
+  -- Extra tools (e.g. alex, hsc2hs, ...) needed to build the source.
+  -- Build-tools:         
+