UserSimulation.Classification.CharErrorRate C# (CSharp) Method

        public double CharErrorRate()
        {
            // find the total number of typo classifications
            var total = _typo_dict.Select(pair => pair.Value).Sum();

            // find the total number of correct classifications
            var t_correct = _typo_dict.Where(pair =>
            {
                OptChar intended_ochar = pair.Key.Item1;
                string entered_str = pair.Key.Item2;
                // an actual character
                if (OptChar.get_IsSome(intended_ochar))
                {
                    var intended_char = intended_ochar.Value;
                    if (intended_char.ToString().Equals(entered_str))
                    {
                        return true;
                    }
                    else
                    {
                        return false;
                    }
                }
                // this is the empty character
                else
                {
                    if (entered_str.Equals(""))
                    {
                        return true;
                    }
                    else
                    {
                        return false;
                    }
                }
            }).Select(pair => pair.Value).Sum();

            return 1 - (double)t_correct / (double)total;
        }