anchor.diff:          evaluation
           |> List.iter (fun (block,quality) ->
               printfn "  %i: %.3f" block (quality.RMSE))
  +
           let overall = evaluation |> Seq.averageBy (fun (_,x) -> x.RMSE)
  +
           printfn "Overall: %.3f" overall
           { RMSE = overall }
   
  
positive.code:         printfn "Loading attributes"
  
          AllAttributes.GetSample().Rows
          |> Seq.map (fun x -> x.Name, x.Value)
          |> Seq.groupBy fst
          |> Seq.map (fun (key,values) ->
              key,
  
negative.code:         printfn "Loading product descriptions"
  
          AllProducts.GetSample().Rows
          |> Seq.map (fun row -> 
              row.Product_uid, 
              row.Product_description |> normalize)
          |> dict
  
      let attributes =
  