A new academic study relevant to investor relations comes from the Booth School of Business, University of Chicago. A study by Eugene Soltes, a graduate student, highlights the important role of the financial press for the investor relations professionals. The results suggest that greater dissemination of news by the company lowers volatility and bid-ask spread for the company’s stock.
You can read more at the IR Magazine blog: http://www.thecrossbordergroup.com/pages/1913/Breaking+news.stm?article_id=13153
Well, it is not a surprise that markets are not really efficient - public information is not equally "public" for all market participants. No Reg. FD can change that. But the difference does not stop at the access to information. Investors also process information differently - they have different understanding of the firm, history of tradings, financial knowledge, expectations, etc.
Hence, the need for the investor relations officer to know how investors access the information and plus to know investors themselves! Good research-based investor relations program can make a difference!