This dissertation consists of three essays in financial economics. The first two essays explore how initial public offerings are affected by various stock market conditions. In the third essay, I study the meaning of innovations in investor sentiment.In the first essay, I use cointegration techniques to decompose stock market shocks into permanent and transitory shocks, building on the idea that transitory shocks should not have long-run effects on dividends and stock prices. The decomposed shocks improve on existing valuation measures by indicating the extent to which market value is driven by permanent or transitory fluctuations. I then examine the effects of these shocks on several aspects of IPOs, and find that (1) despite the lack of l...