period, and more negative for internet IPOs in the post-bubble period. Third, we document that net news increased after a positive stock return, and decreased after a negative stock return for internet firms. This provides some evidence in favor of Shiller's(2000) positive feedback hypothesis. Interestingly, the positive feedback was asymmetric. During the bubble period, net news increases regardless of whether the previous stock return is positive or negative. However, during this bubble period, the increase after a positive stock return was larger for internet IPOs than for non-internet IPOs. These findings reverse in the post-bubble period. In the post-bubble period, net news decreases regardless of whether the previous stock return is positive or negative, however, the decrease in net news after a negative stock return was larger for internet IPOs than for non-internet IPOs. Our results are robust to whether we follow the traditional definition of the bubble in calendar time( the period that ended March 24, 2000)or in event time(the firm- specific period that ended on the day the firms stock price peaked). We, therefore, draw the following conclusion about media coverage of IPOs in the late 1990s: it seems that the overall media coverage was more positive about internet IPOs in the bubble period and more negative about internet IPOs in the post bubble period Did the differential media coverage have any effect on the difference in risk-adjusted returns between internet stocks and non-internet stocks during this period? We check whether news in the media, measured by numbers and type, Granger caused abnormal returns, where abnormal returns is the error term of a Fama-French(1993)three factor model. We incorporate the previous periods abnormal returns as a control when we examined the effect of the media in our analysis. This buys us a few advantages. First, and most important, it corrects for feedback effects: does the media affect returns or do returns affect the media. Both are possible. As a matter of fact, our analysis on aggregate media coverage showed that the latter effect exists. Second, it corrects for possible momentum or reversal in daily stock returns. Third, as the last period's abnormal return contains the cumulative effect of past media reports, it corrects for the possibility that the media effect lasts longer than a day. Finally, because lagged return occurs on the same day as the news reports used for tests, lagged return controls for contemporaneous relationships between stock prices and news coverage. We also control for firm-fixed effects to mitigate the variations in news3 period, and more negative for internet IPOs in the post-bubble period. Third, we document that net news increased after a positive stock return, and decreased after a negative stock return for internet firms. This provides some evidence in favor of Shiller’s (2000) positive feedback hypothesis. Interestingly, the positive feedback was asymmetric. During the bubble period, net news increases regardless of whether the previous stock return is positive or negative. However, during this bubble period, the increase after a positive stock return was larger for internet IPOs than for non-internet IPOs. These findings reverse in the post-bubble period. In the post-bubble period, net news decreases regardless of whether the previous stock return is positive or negative; however, the decrease in net news after a negative stock return was larger for internet IPOs than for non-internet IPOs. Our results are robust to whether we follow the traditional definition of the bubble in calendar time (the period that ended March 24, 2000) or in event time (the firm￾specific period that ended on the day the firm’s stock price peaked). We, therefore, draw the following conclusion about media coverage of IPOs in the late 1990s: it seems that the overall media coverage was more positive about internet IPOs in the bubble period and more negative about internet IPOs in the post￾bubble period. Did the differential media coverage have any effect on the difference in risk-adjusted returns between internet stocks and non-internet stocks during this period? We check whether news in the media, measured by numbers and type, Granger caused abnormal returns, where abnormal returns is the error term of a Fama-French (1993) three factor model. We incorporate the previous period’s abnormal returns as a control when we examined the effect of the media in our analysis. This buys us a few advantages. First, and most important, it corrects for feedback effects: does the media affect returns or do returns affect the media. Both are possible. As a matter of fact, our analysis on aggregate media coverage showed that the latter effect exists. Second, it corrects for possible momentum or reversal in daily stock returns. Third, as the last period’s abnormal return contains the cumulative effect of past media reports, it corrects for the possibility that the media effect lasts longer than a day. Finally, because lagged return occurs on the same day as the news reports used for tests, lagged return controls for contemporaneous relationships between stock prices and news coverage. We also control for firm-fixed effects to mitigate the variations in news