Difference between revisions of "Dynamic Input-Output Models"

From Open Risk Manual
(Formula)
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'''Dynamic Input-Output Models''' is a category of various possible generalization of the basic [[Input-Output Model]] that allow accounting for more sophisticated temporal behavior <ref>Eurostat Manual of Supply, Use and Input-Output Tables, 2008 edition</ref>, <ref>R.E. Miller and P.D. Blair, Input-Output Analysis: Foundations and Extensions, Second Edition, Cambridge University Press, 2009</ref>
 
'''Dynamic Input-Output Models''' is a category of various possible generalization of the basic [[Input-Output Model]] that allow accounting for more sophisticated temporal behavior <ref>Eurostat Manual of Supply, Use and Input-Output Tables, 2008 edition</ref>, <ref>R.E. Miller and P.D. Blair, Input-Output Analysis: Foundations and Extensions, Second Edition, Cambridge University Press, 2009</ref>
  
Dynamic (inter-temporal) frameworks can address phenomena such as stock accumulation (both physical and capital), technology changes and other such time-dependent developments.
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Dynamic (inter-temporal) frameworks can address phenomena such as stock accumulation (both physical and capital), technology changes and other time-dependent developments that cannot be represented in a stationary equilibrium model.
  
Mathematically the equations of the standard IO model become finite difference equations involving one or more timepoints.
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Mathematically the equations of the standard IO model become finite difference equations relating two or more timepoints.
  
 
== Formula  ==
 
== Formula  ==
The typical equations of a dynamic input-output model are:
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Typical equations of a dynamic input-output model are:
* X(t) = A X(t) + C(t) + D(t)
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* <math>X(t) = A X(t) + C(t) + D(t)</math>
 
* D(t) = B (X(t+1) - X(t))
 
* D(t) = B (X(t+1) - X(t))
 
* X(t) = A X(t) + C(t) + B (X(t+1) -X(t))
 
* X(t) = A X(t) + C(t) + B (X(t+1) -X(t))
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== Further Resources ==
 
== Further Resources ==
* [https://www.openriskacademy.com/mod/page/view.php?id=800 Crash Course on Input-Output Model Mathematics]
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* [https://www.openriskacademy.com/course/view.php?id=70 Crash Course on Input-Output Model Mathematics]
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* [https://www.openriskacademy.com/course/view.php?id=64 Introduction to Input-Output Models using Python]
  
 
== References ==
 
== References ==

Revision as of 16:01, 16 November 2023

Definition

Dynamic Input-Output Models is a category of various possible generalization of the basic Input-Output Model that allow accounting for more sophisticated temporal behavior [1], [2]

Dynamic (inter-temporal) frameworks can address phenomena such as stock accumulation (both physical and capital), technology changes and other time-dependent developments that cannot be represented in a stationary equilibrium model.

Mathematically the equations of the standard IO model become finite difference equations relating two or more timepoints.

Formula

Typical equations of a dynamic input-output model are:

  • X(t) = A X(t) + C(t) + D(t)
  • D(t) = B (X(t+1) - X(t))
  • X(t) = A X(t) + C(t) + B (X(t+1) -X(t))
  • (I - A + B) X(t) = C(t) + B X(t+1)


The production of period t is related to the production in period t+1 through equation:


X(t) = (I - A + B)^{-1} (C(t) + B X(t+1) )

while the production of period t+1 is related to the production in period t through equation:


X(t+1) = B^{-1}[(I - A + B) X(t) - C(t) ]

Where:

  • Y Final Demand splits into C + D where
    • C = exogenous final demand (consumption)
    • D = induced investment
  • B = input coefficients for capital (the amount of sector i product (in dollars) held as capital stock for production of one dollar’s worth of output by sector j).
  • I = unit matrix
  • A = input coefficients for intermediate production (Technical Coefficient Matrix)
  • (I - A)^{-1} = matrix of cumulative input coefficients (Leontief Inverse Matrix)
  • t = time index of successive periods


This is a system of linear difference equations, since the values of the variables X are related to different periods of time. NB: In this example the coefficient matrices are assumed time invariant.

Issues and Challenges

  • Practical problems relate to the matrix B of capital coefficients.

Further Resources

References

  1. Eurostat Manual of Supply, Use and Input-Output Tables, 2008 edition
  2. R.E. Miller and P.D. Blair, Input-Output Analysis: Foundations and Extensions, Second Edition, Cambridge University Press, 2009