# How to calculate two-time scale variance?

I am having trouble understanding how to calculate two-time scale variance as I do not have a strong mathematical background. Suppose I want to calculate the TSRV at 5 min intervals. Do I calculate the RV at t = 0,5,10,15min...etc. Then shift the time interval and calculate RV at t = 1,6,11,16min, ....RV at t = 4,9,14,19...and finally take the average of the 5 RVs I have calculated?

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