公司可選擇以公開發行或私募籌措資金，這兩種方式會傳遞不同的資訊，因而有不同的表現；本文比較公開發行與私募的宣告效果及中長期（三年）股價報酬率。研究結果顯示，從事公開現金增資的宣告效果與長期表現都不佳，尤其是發行機會成本較高者，符合資訊不對稱的論點與時點模式。另一方面，公司從事私募的宣告效果為正，籌資後三年的股價報酬率略低於市場報酬率，但高於配對公司，顯示私募有助於公司發展，但並不見得是適合長期投資的標的；本文亦發現，私募公司若給予新股買主較多的補償，短期表現較佳、但長期較差，代表投資人高估了私募的認證效果。

Companies' choice between public offerings (seasoned equity offerings, SEOs) and private placements of equity may convey distinct information and result in different performance. This study investigates that issue by examining announcement and post-issue abnormal returns of companies that make public and private equity offerings. The results show that SEO companies have a negative announcement effect and poor post-issue performance, especially for those with great opportunity costs of issuance. They are consistent with the information asymmetry argument and the timing model. On the other hand, companies conducting private placements elicit a positive response from investors at announcements, and deliver returns slightly lower than the market but higher than their matching sample three years after issue. This suggests that private placements help companies survive, while these companies may not be good targets for long-run investment. We also find that private-placement companies giving greater compensation to new-issue buyers tend to have better short-run but poorer long-run performance, implying that investors overestimate the certification effect.