這裏討論的第一個研究方法是事件研究。這種方法是最著名的。Zollo和Degenhard(2007)對1970年至2006年期間從高級管理和融資期刊獲得的87篇研究論文進行了審查(Laabs和Schiereck, 2010)。他們發現41%的人短期使用事件研究的方法。調查還發現，16%的人使用了長期事件研究方法。該方法涉及到首先考慮一個特定公司在市場估算方面的正常回報。然後用回歸方程對其進行評價。這個方程。這是公司的預期回報。Rmt是市場投資組合回報。I是攔截的術語。Beta I是公司對市場回報的回報敏感性(Kwoka和Pollitt, 2010)。最後一個變量是“e I t”這是零水平擾動平均值的術語。
The first research method discussed here is Event studies. This methodology is the most famous among the others. 87 research papers were reviewed by Zollo and Degenhard (2007) over the performance of acquisition from senior management and financing journals between the period 1970 and 2006 (Laabs and Schiereck, 2010). It was found by them that 41 percent utilized the method of event study for short term. It was also found that 16 percent made use of long term method of event study. The method involves to first consider the normal returns for a particular firm in regards to market estimation. Regression equation is then used to evaluate the same. The equation is. Here Rit is firms expected return. Rmt is market portfolio return. Alpha I is the term interception. Beta I is the return sensitivity over market return in firms (Kwoka and Pollitt, 2010). The final variable is “e I t” which is the term for zero level disturbance mean.
Estimation is done using daily returns rather than the returns after every month. There is a timelines choice available for the researcher. He can utilize to estimate the general returns prior to the event.
This method was utilized for removing any rumoured effect within the market prior to the actual announcement of event. After estimating the normal firm return, then market modelling is utilized for determining a firm’s cumulative return abnormally around the announcement of event.
It is evident from analysing the two methods that the event study method is utilized for a major extent within global studies. The key justification for this is that it provides a direct shareholder value measure and cannot be manipulated (Sharma, 2010). Also, the method has an ease of measurement for firms listed. It shows the influence over the action of firm and over the market rivals. There is one flaw of this method which is the assumption of efficiency in the capital market. This might not be the situation for every market such as this is not the situation for some Asian markets.