With a day’s high, low, open and close, the Parkinson estimator of the daily variance is ; the Garman–Klass estimator is ; the Rogers–Satchell estimator is . The Yang–Zhang estimator over days adds the sample variance of overnight returns, times that of open-to-close returns and times the average Rogers–Satchell term, with .
Quantitative Finance · Glosarium
Apa itu Parkinson, Garman–Klass and Yang–Zhang estimators?
Dikenal juga sebagai: Parkinson estimator · Garman--Klass estimator · Yang--Zhang estimator