remove more spurious perplexity references

Author: soumith

word_language_model/README.md

@@ -5,9 +5,9 @@ By default, the training script uses the Wikitext-2 dataset, provided.
 The trained model can then be used by the generate script to generate new text.
 
 ```bash
-python main.py --cuda --epochs 6        # Train a LSTM on Wikitext-2 with CUDA, reaching perplexity of 117.61
-python main.py --cuda --epochs 6 --tied # Train a tied LSTM on Wikitext-2 with CUDA, reaching perplexity of 110.44
-python main.py --cuda --tied            # Train a tied LSTM on Wikitext-2 with CUDA for 40 epochs, reaching perplexity of 87.17
+python main.py --cuda --epochs 6        # Train a LSTM on Wikitext-2 with CUDA
+python main.py --cuda --epochs 6 --tied # Train a tied LSTM on Wikitext-2 with CUDA
+python main.py --cuda --tied            # Train a tied LSTM on Wikitext-2 with CUDA for 40 epochs
 python generate.py                      # Generate samples from the trained LSTM model.
 ```