英语翻译If one accepts that firms self-selected themselves into

英语翻译
If one accepts that firms self-selected themselves into the sample by making a forecast,then the results of a self-selection bias in publishing forecasts do not necessarily lead to the conclusion that market mechanism "fail" in providing an optimal amount of information about firms to investors(and hence a mandatory disclosure rule is desirable).First,the evidence presentes here indicates that voluntary disclosure dose provide investors with forecast information about some firms.The firms which forecast are distiguished from those that do not and from each other by the level of their forecasts,which have been shown to be related to their values.Second,firms which do not forecast make an implicit forecast("no forecast") and thus can be identified as a group which expects relatively low earnings,to be valued accordingly.Uncertainty exists only with respect to the position of firms within this group relative to each other.Third,managements of firms which do not publish an earning forecast may disclose their earnings expectations through other(lost costly) signals-- for example,dividend announcements,sales forecasts,or a qualitative type of earnings forecast--which may result in "full disclosure." Finally,tha fact that some information is not supplied is not necessarily inconsistent with an optimal allocation of resources to information production.As with any other good,quantities can remain unsupplied at competitive equilibrium,which is considered socially desirable,if the marginal costs of supply are in excess of the marginal benefits.One cannot reach a conclusion about the efficiency of an observed lack of full disclosure without an assessment of the (social) costs and benefits of additional disclosure.

我自己翻译的,想挑战下自己,翻译的不好,你参考一下吧（中间有句实在是翻不出了,就没有写）
如果我们接受企业通过预测对样品做出自我选择,则在公开预测方面,通过自我选择导致偏差的结果并不一定能得出这样的结论：市场机制不能向投资者提供最佳的关于公司的信息数量（因此强制性的公开预测是可取的）.
首先,这里的证据表明,有意的公开预测的数量为投资者提供了关于一些公司的预测信息.那些预测的公司和那些非预测公司被区别开来,而且预测的水平不同,预测的公司也就不同.而他们的预测水平,也已被证明与他们的价值观有关.
其次,有的公司没有作出一个隐含的预测报告（“没有任何预测”）,从而被认为其预计收入相对较低,因此得到重视..
第三,公司的管理层如果不做出一个收入预测报告,可能会通过其他方式公开他们的收入预测.例如,股息通告,销售预测,收入预测的定性类型,这些都可能导致“预测的全公开”.
最后,事实上有些信息并没提供,但这并不一定与对信息生产的最佳的资源分配不相符合.如果少量的供应成本超过了效益,就像其他商品一样,数量可以保持在被认为是社会所需的一个竞争力的水平.我们不能得出这样一个结论：如果不对成本和效益做出额外评价,全公开的效率会明显地下降.