Following Rajgopal and Venkatachalam (2011) and Brown and Kimbrough (2011), the variables used to control for other possible sources of idiosyncratic volatility are: Operating cash flows normalized by assets (CFO/TA) to control for the reported negative association between operating performance and stock return volatility (Hanlon et al. (2004)). The variance of annual operating cash flows normalized by average total assets over the past five years (CFO_δ) to control for the positive association between variance of cash flows and idiosyncratic return volatility (Vuolteenaho (2002)).
Model Specifications Cross-Sectional Tests Base Model (A1) The Base Model to test the effect of earnings non commonality on idiosyncratic risk takes the following form