Through the Economic-Value-Added (EVA) valuation model, the expected market value of equity can be determined by adding the book value of equity with the present value of expected EVAs under the assumption of constant required return and constant return on equity. The equation of EVA valuation model has taken its shape under the assumption of constant required return and constant return on equity. However, a large body of empirical evidence indicates that required rate of return never remain constant. The EVA- valuation model formulated under constant required return cannot be implemented under the scenario of changing required return. In this study, we explored whether the EVA valuation model could be implemented under changing required return by making any changes in the model and found that it could be implemented under the scenario of changing required return by replacing the book value of the equity of the existing model with the present value of required earnings or normal market earnings. We further examined whether the explanatory ability of the EVA valuation model under the assumption of changing required return is better than that of the valuation model under the assumption of constant required return. Relative information content analyses were conducted by considering sample of the intrinsic value of equities determined by valuation models and the market value of equities of 69 large-cap, 88 mid-cap, and 79 small-cap companies. The results showed that the EVA-based valuation model with changing normal market return outperformed the EVA-based valuation model with constant required return.

中文翻译：

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EVA 估值模型是否比不变要求回报更好地解释了变动要求回报下股权的市场价值？

通过经济附加值（EVA）估值模型，在要求报酬不变和权益报酬不变的假设下，将权益的账面价值与预期EVA的现值相加，确定权益的预期市场价值。EVA估值模型方程在要求报酬不变和股本报酬不变的假设下形成。然而，大量的经验证据表明，要求回报率永远不会保持不变。不变要求收益率下制定的EVA-估值模型无法在要求收益率变化的情况下实施。在这项研究中，我们通过对模型进行任何更改来探索EVA估值模型是否可以在要求回报变化的情况下实施，发现它可以在要求回报变化的场景下通过将现有模型的股权账面价值替换为当前所需收入或正常市场收入的价值。我们进一步检验了在要求报酬率变动假设下EVA估值模型的解释能力是否优于要求报酬率不变假设下估值模型的解释能力。通过考虑估值模型确定的股票内在价值样本和69家大盘股、88家中盘股和79家小盘股公司的股票市值，进行了相对信息含量分析。