In the absence of market frictions, differential tax treatments give rise to differences in pre-tax returns across investments, defined as the implicit tax by Scholes and Wolfson (1992).

• 研究结果发现，隐含税负并未与税前报酬率呈现负向关系，此研究结果所代表的意义在于，公司可能在市场上藉由租税优惠，进而获得超额报酬。