EGARCH_VOL - EGARCH Fitted Conditional Volatility Values

Returns an array of the fitted (in-sample) conditional volatilities/standard deviations.

Syntax

EGARCH_VOL ([x], order, µ, [α], [γ], [β])

[X]

Required. Is the univariate time series data (a one-dimensional array of cells (e.g., rows or columns)).

Order

Optional. Is the time order in the data series (i.e., the first data point's corresponding date (earliest date = 1 (default), latest date = 0)).

Value	Order
1	Ascending (the first data point corresponds to the earliest date) (default).
0	Descending (the first data point corresponds to the latest date).

µ

Optional. Is the GARCH model long-run mean (i.e., mu). If missing, the process mean is assumed to be zero.

[α]

Required. Are the parameters of the ARCH(p) component model: [αo α1, α2 … αp] (starting with the lowest lag).

[γ]

Optional. Are the leverage parameters: [γ1, γ2 … γp] (starting with the lowest lag).

[β]

Optional. Are the parameters of the GARCH(q) component model: [β1, β2 … βq] (starting with the lowest lag).

Remarks

1. The underlying model is described here.
2. The time series is homogeneous or equally spaced.
3. The time series may include missing values (e.g., #N/A) at either end.
4. The number of gamma coefficients must match the number of alpha coefficients (minus one).
5. The number of parameters in the input argument - [α_o α_1, α₂ … α_p] - determines the order of the ARCH component model.
6. The number of parameters in the input argument - [β_1, β₂ … β_q] - determines the order of the GARCH component model.

Files Examples

Related Links

• Wikipedia - Autoregressive conditional heteroskedasticity.

References

• James Douglas Hamilton; Time Series Analysis, Princeton University Press; 1st edition(Jan 11, 1994), ISBN: 691042896.
• Tsay, Ruey S.; Analysis of Financial Time Series, John Wiley & SONS; 2nd edition(Aug 30, 2005), ISBN: 0-471-690740.