Before revision:  However, the information about protected attributes in datasets may be inaccurate due to either issues with data collection or when the protected attributes used are themselves predicted by algorithms . Such inaccuracies can prevent existing fair classification algorithms from achieving desired fairness guarantees.
After revision:  However, the information about protected attributes in datasets may be inaccurate due to either issues with data collection or when the protected attributes used are themselves predicted by algorithms . Such inaccuracies can prevent existing fair classification algorithms from achieving their claimed fairness guarantees.