改进灰色预测模型的研究—以安徽省物流量预测为例

以GM(1,1)模型为基础,提出对原始数据取自然对数以提高原始数据的光滑度,同时,与优化背景值相结合,对GM(1,1)模型进行改进。利用安徽物流量的实际数据,比较原始GM(1,1)模型、基于优化背景值的GM(1,1)模型和新的GM(1,1)模型各自的拟合精度,发现新的GM(1,1)模型精度最好,有一定的实用性。     

Delays in reporting price-sensitive information: The case of going concern

Regulators require firms to disclose all price-sensitive information at the earliest possible date. The going-concern opinion constitutes a fundamental uncertainty for the firm and thus is likely to be of a price-sensitive nature. This paper explores whether going-concern uncertainty disclosures are price sensitive in the London market, and then tests whether managements report such audit report information to investors on a timely basis. We capitalize on a London Stock Exchange regulatory loophole which, in effect, allows financially-distressed firms to choose either to report a forthcoming going-concern at the preliminary results announcement stage, or to delay this crucial information to their annual report release. In line with the regulatory requirements, we expect that firms with more price-sensitive, i.e., more serious, adverse news will disclose their forthcoming going-concern opinion at the earliest stage i.e., in their preliminary announcement, rather than delay to their annual report.     

Management Going‐concern Disclosures: Impact of Corporate Governance and Auditor Reputation

The UK regulatory requirements relating to going‐concern disclosures require directors to report on the going‐concern status of their firms. Such directors have incentives not to report fairly in the case of financially‐distressed firms. We expect effective corporate governance mechanisms will encourage directors to report more truthfully in such situations. This paper tests this proposition explicitly using a large sample of going‐concern cases over the period 1994–2000. We find that whereas auditors' going‐concern opinions predict the subsequent resolution of going‐concern uncertainties directors' going‐concern statements convey arbitrary and unhelpful messages to users. However, robust corporate governance structures and high auditor reputation constrain directors to be more truthful in their going‐concern disclosures, bringing these more into line with the more credible auditor opinions.