1 Introduction -- 2 Microstructure Foundations -- 3 Empirical Properties of High-Frequency Data -- 4 Financial Point Processes -- 5 Univariate Multiplicative Error Models -- 6 Generalized Multiplicative Error Models -- 7 Vector Multiplicative Error Models -- 8 Modelling High-Frequency Volatility...

From 1963 through 2015, idiosyncratic risk (IR) is high when market risk (MR) is high. We show that the positive relation between IR and MR is highly stable through time and is robust across exchanges, firm size, liquidity, and market-to-book groupings. Though stock liquidity affects the...