Correct readme

README.md

@@ -119,7 +119,7 @@ The output for different modes and error_formats is:
 ```
 
 ```python
->>> faireval.compute(predictions=y_pred, references=y_true, mode='traditional', error_format='proportion')
+>>> faireval.compute(predictions=y_pred, references=y_true, mode='traditional', error_format='error_ratio')
 {'PER': {'precision': 0.5, 'recall': 0.5, 'f1': 0.5, 'TP': 1, 'FP': 0.1428, 'FN': 0.1428},
  'INT': {'precision': 0.0, 'recall': 0.0, 'f1': 0.0, 'TP': 0, 'FP': 0.1428, 'FN': 0.2857},
  'OUT': {'precision': 0.5, 'recall': 0.5, 'f1': 0.5, 'TP': 1, 'FP': 0.1428, 'FN': 0.1428},