Jay Ritter, a professor at the University of Florida, was quoted in the Wall Street Journal as

Question:

Jay Ritter, a professor at the University of Florida, was quoted in the Wall Street Journal as saying about Facebook: "It's entirely possible for a company to have solid growth prospects while its stock is overvalued."
a. What does it mean to say that a stock is "overvalued"?
b. Why might a firm's stock be overvalued despite the firm having "solid growth prospects"?