Iwatsuka Confectionery Co APARCH Volatility Analysis

Model Insight

With persistence 0.993, volatility shocks have a half-life of 99 trading days (~0.4 years), close to a unit root, so long-run forecasts are highly sensitive to this estimate. The volatility power δ = 1.76 sits below 2, so large shocks influence volatility less than quadratically, a more outlier-robust response than standard GARCH.

Inverse leverage: Positive returns increase volatility 61% more than negative returns