Model ct
CT model class.
CentTend
Bases: SDE
Central Tendency model.
__init__(param=None)
Initialize the class.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
True parameters used for simulation of the data |
None
|
coef_big_as(*, param, aggh)
staticmethod
Coefficient A^\sigma_h in exact discretization of volatility.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
Coefficient A^\sigma_h |
coef_big_ay(*, param, aggh)
staticmethod
Coefficient A^v_h in exact discretization of volatility.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
|
coef_big_bs(*, param, aggh)
Coefficient B^\sigma_h in exact discretization of volatility.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
Coefficient B^\sigma_h |
coef_big_cs(*, param, aggh)
Coefficient C^s_h in exact discretization of volatility.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
Coefficient C^s_h |
coef_big_cy(*, param, aggh)
Coefficient C^y_h in exact discretization of volatility.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
Coefficient C^y_h |
coef_small_as(*, param, aggh)
Coefficient a^s_h in exact discretization of volatility.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
Coefficient a^s_h |
coef_small_ay(*, param, aggh)
Coefficient a^v_h in exact discretization of volatility.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
|
coef_small_bs(*, param, aggh)
Coefficient b^s_h in exact discretization of volatility.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
Coefficient b^s_h |
coef_small_cs(*, param, aggh)
Coefficient c^s_h in exact discretization of volatility.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
Coefficient c^s_h |
get_start()
Return starting values for simulation.
mat_a(*, param, subset=None)
Matrix A in integrated moments.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
subset
|
slice
|
Which moments to use |
None
|
Returns:
| Type | Description |
|---|---|
(nmoms, 3*nmoms) array
|
Matrix A |
mat_a0(*, param, aggh)
Matrix A_0 in integrated moments.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
(4, 4) array
|
Matrix A_0 |
mat_a1(*, param, aggh)
Matrix A_1 in integrated moments.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
(4, 4) array
|
Matrix A_1 |
mat_a2(*, param, aggh)
Matrix A_2 in integrated moments.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
(4, 4) array
|
Matrix A_2 |
mat_a3(*, param, aggh)
Matrix A_3 in integrated moments.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
(4, 4) array
|
Matrix A_3 |
mat_a4(*, param, aggh)
Matrix A_4 in integrated moments.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
(4, 4) array
|
Matrix A_4 |
mat_a5(*, param, aggh)
Matrix A_5 in integrated moments.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
(4, 4) array
|
Matrix A_5 |
mean_cross(*, param, aggh)
Unconditional mean of realized returns times volatility.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
|
mean_ret(*, param, aggh)
staticmethod
Unconditional mean of realized returns.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
|
mean_vol(*, param, aggh)
staticmethod
Unconditional mean of realized volatiliy.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
|
mean_vol2(*, param, aggh)
Unconditional mean of squared realized volatiliy.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
|
realized_const(*, param=None, aggh=1, subset=None)
Intercept in the realized moment conditions.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
None
|
aggh
|
float
|
Interval length |
1
|
subset
|
slice
|
Which moments to use |
None
|
Returns:
| Type | Description |
|---|---|
(4, ) array
|
Intercept |
realized_depvar(*, data, subset=None)
staticmethod
Array of the left-hand side variables in realized moment conditions.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
data
|
(2, nobs) array
|
Returns and realized variance |
required |
subset
|
slice
|
Which moments to use |
None
|
Returns:
| Type | Description |
|---|---|
(nobs, 5*nmoms) array
|
Dependend variables |
roots(*, param, aggh)
Roots of the polynomial in moment restrictions.
.. math::
\left(1-A_{2h}^{\sigma}L\right)
\left(1-A_{2h}^{y}L\right)
\left(1-A_{h}^{\sigma}A_{h}^{y}L\right)
\left(1-A_{h}^{y}L\right)
\left(1-A_{h}^{\sigma}L\right)
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
list of floats
|
|
unc_mean_ct2(param)
Calculate unconditional second moment of CT, E[y_t**4].
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
Returns:
| Type | Description |
|---|---|
float
|
|
unc_mean_sigma2(param)
Calculate unconditional second moment of volatility, E[\sigma_t**4].
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
Returns:
| Type | Description |
|---|---|
float
|
|
unc_var_ct(param)
Calculate unconditional variance of CT, V[y_t**2].
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
Returns:
| Type | Description |
|---|---|
float
|
|
unc_var_error(*, param, aggh)
Calculate unconditional variance of aggregated volatility error.
:math:V\left[\frac{1}{H}\int_{0}^{H}\epsilon_{t,s}^{\sigma}ds\right].
Derived symbolically in symbolic.py
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
aggh
|
float
|
Interval length |
required |
Returns:
| Type | Description |
|---|---|
float
|
|
unc_var_sigma(param)
Calculate unconditional variance of volatility, V[\sigma_t**2].
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
param
|
parameter instance
|
Model parameters |
required |
Returns:
| Type | Description |
|---|---|
float
|
|