A Comment on: “Autoregressive Conditional Duration: A New Model for Irregularly Spaced Transaction Data”
评《自回归条件持续时间:不规则间隔交易数据的新模型》
Based on the GARCH literature, Engle and Russell (1998) established consistency and asymptotic normality of the QMLE for the autoregressive conditional duration (ACD) model, assuming strict stationarity and ergodicity of the durations. Using novel arguments based on renewal process theory, we show that their results hold under the stronger requirement that durations have finite expectation. However, we demonstrate that this is not always the case under the assumption of…