DISCUSSION OF Timely Industry Information as an Assurance Service--Evidence on the Information Content of the Book-to-Bill Ratio.
讨论非强制鉴证服务，研究半导体行业订单出货比（BTB）信息对投资者的价值，发现投资者仅在BTB上升（好消息）时调整预期，但证据较弱且仅关注最大变化。
Abstract This article discusses the issue of nonmndated assurance services. The primary research question addressed by earlier researchers is whether the information resulting from an assurance service (e.g., assimilation and release of the monthly book to bill ratio in the semiconductor industry) is of value to capital market participants. The researchers, in a competent and thorough manner, use an event study methodology to provide empirical evidence on this question. Their evidence suggests that investors use the book-to-bill (BTB) ratio in revising their expectations of future cash flows for firms in the semiconductor industry. However, it appears that the information is only used when it represents "good news" (i.e., increases in BTB). And, as acknowledged by the researchers, the results are somewhat weak. Of greater concern is the fact that their test focuses only on the largest increases and decreases in the BTB, and thereby provides results only weakly supporting the hypothesis that share prices of semiconductor firms respond to changes in the BTB.