public decimal score(string x, Classification c)
        {
            decimal sum = 0;
            foreach (string w in Tokenizer.tokenize(x))
            {
                if (PxiC[c].ContainsKey(w))
                {
                    decimal val = PxiC[c][w] / (1 - PxiC[c][w]);
                    if (val != 0 || val > 0)
                    {
                        sum += (decimal)Math.Log((double)val);
                    }
                }

            }

            return emptyScore[Classification.Positive] + sum;
        }