Efficiency Evaluation and Pareto Solution in WY Model

WY model has been proven to be an efficient method for congestion and returns to scale in Data Envelopment Analysis (DEA). In this paper, we research the relationship between technical efficient and pare to solution in WY model. We prove that if a DMU is a pare to solution in WY model, it must be DEA technically efficient. However, the converse may not true. The condition for a technically efficient DMU to be a pare to solution is also discussed. Numerical example is provided for illustration.