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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