As the shares of social networking giant Facebook begin trading on the NASDAQ exchange today, experts believe that the stock is overpriced at USD 38 apiece and one must wait for now to invest in the firm.     

NYU Stern School of Business Finance ex-Professor Kenneth Froewiss said that adding Facebook to a portfolio early on is risky for experienced pros and investment amateurs alike.

"Even for those individuals with above-average net worth, purchasing shares at an IPO, especially a 'hot' one that has been widely hyped, is rarely a good idea," Froewiss said. He said it is like playing a lottery. "Might someone on occasion reap a tremendous windfall by doing so? Yes, but then again, on occasion someone wins the lottery. That does not make the lottery a great investment in general," he added.