QuantLib: a free/open-source library for quantitative finance
fully annotated source code - version 1.34
Loading...
Searching...
No Matches
Public Member Functions | Private Attributes | List of all members
BlackKarasinski::Dynamics Class Reference

Short-rate dynamics in the Black-Karasinski model. More...

#include <blackkarasinski.hpp>

+ Inheritance diagram for BlackKarasinski::Dynamics:
+ Collaboration diagram for BlackKarasinski::Dynamics:

Public Member Functions

 Dynamics (Parameter fitting, Real alpha, Real sigma)
 
Real variable (Time t, Rate r) const override
 Compute state variable from short rate. More...
 
Real shortRate (Time t, Real x) const override
 Compute short rate from state variable. More...
 
- Public Member Functions inherited from OneFactorModel::ShortRateDynamics
 ShortRateDynamics (ext::shared_ptr< StochasticProcess1D > process)
 
virtual ~ShortRateDynamics ()=default
 
virtual Real variable (Time t, Rate r) const =0
 Compute state variable from short rate. More...
 
virtual Rate shortRate (Time t, Real variable) const =0
 Compute short rate from state variable. More...
 
const ext::shared_ptr< StochasticProcess1D > & process ()
 Returns the risk-neutral dynamics of the state variable. More...
 

Private Attributes

Parameter fitting_
 

Detailed Description

Short-rate dynamics in the Black-Karasinski model.

The short-rate is here

\[ r_t = e^{\varphi(t) + x_t} \]

where \( \varphi(t) \) is the deterministic time-dependent parameter (which can not be determined analytically) used for term-structure fitting and \( x_t \) is the state variable following an Ornstein-Uhlenbeck process.

Definition at line 74 of file blackkarasinski.hpp.

Constructor & Destructor Documentation

◆ Dynamics()

Dynamics ( Parameter  fitting,
Real  alpha,
Real  sigma 
)

Definition at line 77 of file blackkarasinski.hpp.

Member Function Documentation

◆ variable()

Real variable ( Time  t,
Rate  r 
) const
overridevirtual

Compute state variable from short rate.

Implements OneFactorModel::ShortRateDynamics.

Definition at line 82 of file blackkarasinski.hpp.

◆ shortRate()

Real shortRate ( Time  t,
Real  variable 
) const
overridevirtual

Compute short rate from state variable.

Implements OneFactorModel::ShortRateDynamics.

Definition at line 84 of file blackkarasinski.hpp.

Member Data Documentation

◆ fitting_

Parameter fitting_
private

Definition at line 87 of file blackkarasinski.hpp.