本論文的目的，在探討我國自願性財物預測公告與公告與證券信用交易之間的關係。信用交易的增減代表使用信用交易的投資者對某特定資訊的瞭解與使用，因此實證檢視財務預測的修正行為與信用交易增減的關係，可以敏銳地瞭解，是種特定投資者在哪個時點對財務預測修正進行理性預期，並予使用且做了較實際的交易行為。因此，本研究的測試可以瞭解使用信用交易的投資者如何使用財務預測等相關資訊。據此，本研究的結果有助於了解使用信用交易的投資者如何運用自願性財務預測資訊來做投資決策。

研究期間是以民國八十四年至八十六年的資料為分析的對象，研究的結果顯示：

一、在季報（半年報、年報）公告前公佈的財務預測，好消息會引起融資顯著增加，融券增加幅度雖不如融資大，但結果亦為顯著；壞消息會使融資及融券同樣顯著增加，但融資增加幅度亦較融券顯著。

二、在季報（半年報、年報）公告後公佈的財務預測，好消息會引起融資顯著增加，融券增加幅度雖不如融資大，但結果亦為顯著；壞消息會使融資及融券同樣顯著增加，但融資增加幅度亦較融券顯著。

This study aims to examine the relationship between an announcement of voluntary forecasts and credit transactions, including margin and short transactions. In general, an announcement of good news would attract investor to employ margin for a long position, and vice versa. Since only noisy trader can employ credit transaction in Taiwan, this study hypothesizes that investors would follow the announcement for making rational expectation. The results of this study could help understand how noisy traders use a financial forecast. This study selects the samples occurred between 1995 and 1997 to test the established hypotheses.

The empirical results can be summarized as follows.

● If the announcement of voluntary forecast occurred prior to the release of quarterly, semiannual, and annual reports, both good and bad news simultaneously cause an increase of margin and short transactions during this period. However, the magnitude of margin transactions is significantly higher than that of short transactions.

● If the announcement of voluntary forecast occurred subsequent to the release of quarterly, semiannual, and annual reports, both good and bad news simultaneously cause an increase of margin and short transactions during this period; however, the magnitude of margin transaction is significantly higher than that of short transaction.

Since noisy traders are essentially information follower, their judgement significantly relates to functional efficiency of informational intermediaries. These empirical results imply the function of informational intermediaries requires further improvement.