管理层权力理论

Assessing Managerial Power Theory:A Meta-Analytic Approach to Understanding the Determinants of CEO Compensation 评价管理层权力理论（MPT）：用元分析的方法来理解CEO薪酬的的决定因素
Marc van Essen（Utrecht University）. 2015, Journal of Management：164-203
一、提出问题
尽管对CEO薪酬的研究在不断增加，但是关于形成高管薪酬类型的基本决定因素，各学科之间仍缺少共识。

这种缺少的共识最常见的在：
一方面：提倡基于市场解释的经济和金融学者
另一方面：经济和金融学科之外的学者挑战这些解释，他们主在薪酬实践创新过程中强调权力、社会心理过程和机构环境的重要性。

这种差异引起了更多有创造性的讨论，最近对纯粹基于市场解释最杰出的挑战是管理层权力理论（MPT）。

这个理论由Bebchuk and Fried (Bebchuk & Fried, 2004; Bebchuk, Fried, & Walker, 2002)推动。

这个理论框架的核心是对代理理论最优契约假设的一种直接挑战。

最优契约理论中，董事会致力于和高管在薪酬安排上达成正常交易；这种正常交易可以通过建立高管和股东利益最紧密连接的薪酬机制来解决代理问题。

相反，Bebchuk and Fried （2004）发现，董事会很少致力于建立这种正常交易，因为企业特殊的结构和社会心理机制会对董事会制定高管薪酬的决策过程产生很重要的影响，所以CEOs通常会拥有比董事会更大的权力。

这些机制为董事会提供了了新的动机来挑战薪酬安排，而这样的安排更偏向高管的利益而不是股东的利益，也就是董事会提供了更高层次的薪酬以及与业绩不太相关的薪酬。

MPT的目标不是反驳代理理论，而是去深化，通过提出管理层权力和它对高管薪酬的影响引起了对最优契约假设的质疑。

一些经济和金融领域的学者用了多种类型的证据反过来批评了MPT，虽然他们对MIP 范围和影响提出了很重要的问题，但是对于MPT有效性，他们没有提供有效的决定性的证据来反驳。

Bebchuk and Fried （2004）已经直接提出了对这些批评的直接抗辩。

最重要的是在公司层面，大部分挑战没有基于对管理层权力和薪酬支出指标关系的直接检验。

相反，这些批评倾向于集中在集团层面相关的董事会独立性、薪酬、公司业绩和CEO 更替。

因此，我们主张用两个核心的问题来检验MPT的有效性：
1.比董事会拥有更多权力的CEO是否比拥有较少权力的CEO有更高的薪酬？
2.比董事会拥有更多权力的CEO是否有跟公司业绩不相符（对公司业绩不敏感）？
已经有大量和多样的研究在公司层面实证检验了这些关系，然而这些文献仍然是不确定性的，特点就是不同的和冲突的发现允许支持者和反对者对不同的结论进行论证。

所以，现阶段需要一个对现存文献更严格的评价方法，能够巩固这种混合的实证发现以及从薪酬水平和薪酬业绩敏感性的角度来评价对MPT有效性的一般解释。

这篇文章我们用元分析的方法提供了一种对现有文献巩固和评价。

元分析（meta-analysis )统计方法是对众多现有实证文献的再次统计，通过对相关文献中的统计指标利用相应的统计公式，进行再一次的统计分析，从而可以根据获得的统计显著性等来分析两个变量间真实的相关关系。

元分析是一种有用和稳健的方法，用来分析在大量研究中已经被检验过的变量之间的关系。

当存在大量混合结果和冲突结果研究的情形下，元分析方法提供了综合和严密的评价来均衡最接近结果的数据证据。

二、研究方法
We use these techniques to assess the accumulated evidence of 219 studies that measure the influence of managerial power directly on both CEO compensation levels and the relationship between corporate performance and CEO pay.
If our analysis finds higher levels of pay and pay that is less sensitive to performance when executives have more power, and the opposite when directors have more power, this will provide empirical evidence in favor of MPT.
To test these predictions, scholars have relied on a number of different indicators of CEO and board power
We focus on the two sets of mechanisms on which researchers have focused most frequently when analyzing managerial power: board structures and ownership characteristics
三、研究假设
Board Characteristics
Variables：CEO duality,CEO tenure, size of the board, and the percentage of independent directors
Hypothesis 1a: CEO duality is positively associated with the value of total CEO compensation.
Hypothesis 1b: In the presence of CEO duality, the association between corporate performance and CEO compensation will be weaker.
Hypothesis 2a: CEO tenure is positively associated with the value of total CEO compensation.
Hypothesis 2b: In the presence of CEOs with longer tenure, the association between corporate performance and CEO compensation will be weaker.
Hypothesis 3a: Board size is positively associated with the value of total CEO compensation.
Hypothesis 3b: In the presence of larger boards, the association between corporate performance and CEO compensation will be weaker.
Hypothesis 4a: The percentage of independent directors is negatively associated with the value of total CEO compensation.
Hypothesis 4b: At higher levels of board independence, the relationship between corporate performance and CEO compensation will be stronger.
Ownership Characteristics
Variables：concentrated ownership, institutional ownership
Hypothesis 5a: Higher levels of concentrated ownership is negatively associated with the value of total CEO compensation.
Hypothesis 5b: At higher levels of concentrated ownership, the association between corporate performance and CEO compensation will be stronger.
Hypothesis 6a: Higher levels of institutional ownership is negatively associated with the
value of total CEO compensation.
Hypothesis 6b: At higher levels of institutional ownership, the association between corporate performance and CEO compensation will be stronger.
四、研究设计
Model:
where Ri is the partial correlation between firm performance and CEO total compensation,y0 is the constant term, D is a vector of whether a particular variable is included in a regression or not, S is a vector of measurement artifacts, R is a vector of study characteristics, and ui is the random component.
we included in the D vector a set of dummy variables indicating whether the following variables were included in the regression (0) or not (1): CEO duality, CEO tenure, board size, board independence, ownership concentration, and institutional ownership.
we included in the S vector several control variables. To control for the influence of measurement artifacts on effect sizes
we included in the R vector three other control variables. To control for theinfluence of study artifacts
五、研究结果：
1.CEO Total Compensation
Hypothesis 1a, which predicts that CEO duality is positively related to the level of total CEO compensation, is confirmed by the results in Table 4. We find that CEO duality is positively related to CEO total pay (b = .02, p < .05). We find no support for Hypothesis 2a that CEO tenure is
positively related to CEO compensation levels (b = –.00, p > .05). We find clear support for Hypothesis 3a, as the size of boards is associated with higher levels of total pay (b = .12, p < .01). In fact, after firm size, board size has the largest impact on total pay. In contrast to the prediction of Hypothesis 4a, the degree of board independence is positively related to total pay levels (b = .06, p < .01). Our findings also provide support for Hypothesis 5a: As hypothesized, concentrated ownership is negatively related to the level of total CEO compensation (b = –.04, p < .01). Finally, we find support for Hypothesis 6a that the presence of higher levels of institutional ownership is associated with lower levels of total pay (b = –.03, p < .01).
2.Performance–Pay Sensitivity
The MARA results, as reported in Table 5, do not provide support for Hypothesis 1b. CEO duality has no significant moderating effect on the performance–pay relationship. We find support for Hypothesis 2b, which predicts that the presence of CEOs with longer tenure negatively moderates the performance–pay relationship. The results show that studies that
fail to control for CEO tenure in their regression analyses find a weaker performance–pay relationship (Doucouliagos & Ulubaşoğlu, 2008). Hence, in the presence of CEOs with longer tenure, the association between firm performance and CEO compensation becomes weaker. In contrast to Hypothesis 3b, we find that in the presence of larger boards, the association between firm performance and CEO compensation actually becomes stronger. We find support for Hypothesis 4, that board independence positively moderates the performance–pay relationship. However, we find no moderating effect of ownership concentration on the performance–pay relationship, as hypothesized by Hypothesis 5b. Finally, we find support for Hypothesis 6b, as institutional ownership positively moderates the performance–pay relationship.
In assessing the evidence regarding the relationship between managerial power and total compensation levels, we find overall support for MPT.Two of the three indicators of CEO power (board size and CEO duality) are positively associated with total pay, suggesting that in most situations where CEOs are expected to have more power over the pay setting process, they have higher levels of total compensation. Similarly, two out of the three indicators of board power (ownership concentration and institutional ownership) are negatively associated with total pay, suggesting that in most situations where boards have more power over the pay setting process, CEOs have lower total compensation. The two exceptions to these patterns are that board independence is positively associated with total compensation and the effect of CEO tenure is not significantly related to total compensation.
The results for performance–pay sensitivities provide less support for MPT. Only one of the indicators of CEO power (CEO tenure) is statistically significant and in the expected negative direction, whereas CEO duality is not significant, and board size is significant but in the opposite (positive) direction. However, two out the three indicators of board power (board independence and institutional ownership) are significant and in the expected positive direction, but ownership concentration is not significant.
These results suggest that MPT is better able to explain total pay levels than performance–pay sensitivities. They further suggest that even powerful CEOs have a difficult time mitigating the performance–pay link.
六、研究不足和未来研究方向
The first is the somewhat problematic interpretation of certain indicators as proxies for managerial or director power.
Another limitation of our analysis is that the majority of studies included in our sample have
relied on data drawn from samples of large U.S. corporations, such as the S&P 500, and may not be generalizable beyond this sample.
In addition, to be able to assess our predicted relationships through meta-analysis, we required a large enough sample of effect sizes, which naturally limited the number of variables we could test.
Finally, it is important to highlight the relatively small percentage of variance explained by indicators of CEO and board power.。