The half-life is used to estimate the adjustment speed of a variable to a new equilibrium point after being affected by the impulse response of a unit of shocks. The paper examines the adjustment speed of COVID19, investor sentiment, and the stock market through half-life estimates over the...

In this chapter, we estimate the Expected Shortfall (ES) in conditional autoregressive expectile models by using a nonparametric multiple expectile regression via gradient tree boosting. This approach has the advantages generated by the flexibility of not having to rely on data assumptions and...