What is a good way to think about and estimate VIX half life?

Would it make sense to run an AR(1) regression to estimate a beta and then estimate the half life as -ln(2)/beta?

1. Why do you limit yourself to an AR(1)? You can solve for $$h$$ in $$E_t(y_{t+h})=y_t/2$$ for other models too. If you want to stick to simple stuff, stay with the class of ARMA models, but check if you can have a better fit with an ARMA(1,1) or using more lags in your autoregression. To be entirely fair, it's possible nonlinear models would fit better, but then you'd have to solve for $$h$$ numerically in many cases.