This dissertation consists of three studies on cross-sectional pricing in equity market. The first chapter discusses co-jumps. I use high-frequency stock returns to estimate downside jump beta and upside jump beta, and find that downside jump beta is greater than upside jump beta for most stocks included in Dow Jones 30 Index. I propose a measure for co-jump asymmetry (CJA) and find that stocks with high CJA (more left-skewed co-jumps) significantly outperform their counterpart. The prediction effects of CJA are stronger for moreliquid and less volatile stocks, implying that the relation between CJA and cross-sectional stock returns is driven by risk-return trade-off rather than the behavioral bias of risk-seeking investors. In the seco...