Wrong formula for close to close and Garman Klass

Options & Futures
1

Course Name: Options Volatility Trading: Concepts and Strategies, Section No: 14, Unit No: 1, Unit type: WaterMarkVideo

The formula and the explanation for the Garman-Klass estimator is wrong it does not account for the opening price.

In addition, the formula for the close to close estimator is also not this
$$ \text{Close-to-Close Volatility} = \sqrt{ \frac{1}{N}\sum_{i=1}^n (\frac{r_i}{\bar r})^2 } $$

2

Hi,

We are currently looking into this and will get back to you.

3

Hi Anthony,

Thank you for pointing this out. We are reviewing the content and will work on your inputs.