From the point of view of Adj-R2, a

From the point of view of Adj-R2, after the M & A happened, I was born Tobin Q difference and total asset return difference between the first year, the second year and the third year and the end of the year before the merger and acquisition The regression goodness of fit of model 1 and model 2 is much higher than that of the year of M & A and the year before M & A The difference between the last year of M & A and the last year of M & A is due to the difference of Tobin Q and the total capital of M & A The yield-return difference both covers the pre-merger performance of some mergers and acquisitions, resulting in the Tobin Q difference and the total capital spool According to the time of M & A, the difference of yield and return is different. From model 1 and model ２ The first year, the second year, the third year and the last year of M & A The total asset return difference is higher than the Tobin Q difference according to the regression goodness of fit of model 2 The regression goodness of fit is due to the fact that the method of calculating the Tobin Q value itself depends on the securities The market is fully effective, and the stock market of our country still does not meet this requirement, but from the concrete regression result comes the rickshaw See, there is some similarity between the difference of Tobin Q and the difference of total return on assets, which can be proved to be the use of the difference Tobin Q value calculation of M & A performance is effective. 