Most economic time series, such as GDP, real exchange rate and banking series are irregular by nature as they may be affected by a variety of discrepancies, including political changes, policy reforms, import-export market instability, etc. When such changes entail serious consequences for time...

This paper proposes new estimators for the daily return variance which are based on common intraday statistics (opening, high, low, and closing prices). These estimators utilize information contained in products of absolute values of uncorrelated intraday statistics. An empirical study of nine...