能翻多少是多少吧，谢谢大家了！
3.3. Independent variables
The independent variables consisted of the proportion of outside directors and their stock ownership. The percentage of outside board members consisted of the number of board members who have not been employed by or have had no discernable business relationship with the firm on whose board they serve, divided by the total number of board members. Outside board stock ownership consisted of the total number of each corporation’s shares owned by its outside directors divided by the total number of that firm’s shares outstanding.
3.4. Control variables
Our control variables included firm size, the relatedness of acquisitions, industry ROA percentage change, and an economic indicator. We controlled for size and relatedness because of their potential effects on acquisition outcomes (Franks et al., 1991; Wright et al., 2002a). Size was proxied by the log of sales in constant 1987 dollars. A dummy variable (scored 0 if the acquirer and the target did not share the same two-digit SIC codes and 1 if they did) was used to represent relatedness. Some scholars have contended that related diversification may be desirable (Amihud and Lev, 1981; Bethel and Liebeskind, 1993), while others have
suggested that unrelated acquisitions may be beneficial (Lubatkin, 1987; Walsh and Seward, 1990). As one of our dependent variables was year-over-year percentage changes in ROA, we also included an industry ROA percentage change variable to control for industry specific factors. The industry ROA percentage change figures represent the averages of changes in ROA values for all the firms in the Compustat database with the same two-digit SIC codes as each of the firms in the sample. We calculated the industry average percentage change figures for the same period used to estimate the acquiring firms’ percentage changes in ROA values, and followed the same approach described earlier. Additionally, we included a dummy variable (scored 0 if the acquisitions were announced during an economic contraction and 1 if announced during an economic expansion) to control for economic conditions that might influence acquisition outcomes.

13.3.3.独立变量
独立变量由外部董事百分比及其股权组成。外部董事百分比指不受他们所服务公司雇佣或与之无可辨识的生意来往外部董事人数除以董事总人数。外部股权指外部董事控股总额除以公司已发行股票总额。
3.4.控制变量
我们的控制变量包括公司规模，收购关联度，行业资产收益率百分比变化，以及另一个经济指标。我们控制规模与关联度是因为它们在收购成本上的潜在影响。（弗兰克等人，1991；赖特等人，2002a）。公司规模由1987年定值美元代理销售记录来定。一个虚拟变量（记作0，如果收购公司和目标公司是相同的两位数的标准行业分类代码，否则记作1）用来代表关联度。一些学者主张相关的多样化经营也许是可取的。（阿米胡德和列弗，1981；贝瑟尔和利伯斯金，1993） 而其它一些人则建议不相关的多样化经营会更有益（卢巴金，1987；沃尔什和舍沃德，1990）。逐年的资产收益率百分比变坏作为我们相依变量中的一个，我们同样包括了一个行业资产收益率百分比变化变量来控制行业特定因素。行业资产收益率百分比变化的数值代表了 Compustat数据库中所有在案例中的具有相同的两位数的标准行业分类代码的公司的平均资产收益率百分比变化。我们计算同一段时间行业平均百分比变化用来估计收购公司资产收益率百分比变化值，采用的是前面所描述的相同的方法。另外，我们采用了另一个虚拟变量（在经济衰退时宣布的收购记作0，在经济扩招时宣布的记作1）来控制经济环境可能对收购成本造成的影响。