The Turning Point of Macroeconomics?

Transcription

1 ETH Zürch Ivtato for Macro-Ecoophyscs 30, November 200 Hrosh Yoshkawa Uversty of Tokyo The Turg Pot of Macroecoomcs? The Facal Crss (2005= Exports 0 00 IdustralProducto Source: METI, Cabet Offce Macroecoomcs was bor as a dstct feld the 940 s, as a part of the tellectual respose to the Great Depresso. The term the referred to the body of kowledge ad expertse that ecoomc dsaster. My thess ths lecture s that macroecoomcs ths orgal sese has succeeded: Its cetral problem of depresso preveto has bee solved, for all practcal purposes, ad has fact bee solved for may decades. Robert Lucas, Nobel Laureate Presdetal Address to the 2003 Amerca Ecoomc Assocato

2 Most macroecoomcs of the past 30 years was spectacularly useless at best, ad postvely harmful at worst. Paul Krugma Jue 2009 at Loel Robbs Lectures Lodo School of Ecoomcs Neoclasscal Ecoomcs Prce Mechasm or Markets Pareto Effcecy Adam Smth (776 Ivsble Had The most terestg recet developmets macroecoomc theory seem to me descrbable as the recorporato of aggregatve problems such as flato ad the busess cycle wth the geeral framework of mcroecoomc theory. If these developmets succeed, the term macroecoomc wll smply dsappear from use ad the modfer mcro wll become superfluous. Robert Lucas (987 The Adustmet of Prce Equates Demad for ad Supply of Apples Prce of Apple P * S D Quatty of Apples Q *

3 Behd Demad ad Supply Curves. The Margal Utltes of All the Cosumers (=,,J out of Cosumg Apples are Equal to the Prce. U ( C C P Equlbrum As a Pot Equlbrum As a Dstrbuto Ad the Margal Products of All the Producers (k=,,k to Produce Apples are Equal to the Prce. F ( L L P To Aalyze Equlbrum as a Dstrbuto, We Need Resort to the Methods of Statstcal Physcs. Equlbrum As a Pot

4 Are Ecoomc Behavor ad Moto of Partcle Fudametally Dfferet? Thus, Ecoomcs must be based o Mcroecoomc Aalyss of Purposeful Ecoomc Behavor Most Ecoomsts Thk They are Fudametally Dfferet. Ths Leads Us to the Aalyss based o the Represetatve Aget.

5 Welfare Calculato by Robert Lucas (987 Based o the Represetatve Cosumer If busess cycles of the magtude expereced sce WW II were elmated completely, ths would rase the level of utlty by oly $8.50 per perso! Facal Markets Tradtoal Face Effcet Market Theory Ecoophyscs Facal Bubbles Macroecoomcs Cosumpto-Based Captal Asset Prcg Model Real Ecoomy Facal Markets u"( C C u' ( C where C C ( C C C r ( C u"( C C u' ( C 0

6 Real Ecoomy Aalyss of Network Comprsg May Heterogeeous Agets Keyesa Ecoomcs Uemploymet Neoclasscal Ecoomcs Full Employmet Mcroecoomc Foudatos for Keyesa Ecoomcs

7 What Matters Is Not Employmet or Uemploymet 0 or But May Levels of Productvty amely Dstrbuto of Productvty Mcroecoomc Foudato for Keyesa Ecoomcs The Prcple of Statstcal Physcs Boltzma or Expoetal Dstrbuto statoary state Yoshkawa, H. (2003 The Role of Demad Macroecoomcs, Japaese Ecoomc Revew, Vol.54, No., -27.

8 Gbbs Dstrbuto Dstrbuto Chages as Aggregate Demad Chages Source : Aok M. ad H. Yoshkawa, (2007 Recostructg Macroecoomcs: A Perspectve from Statstcal Physcs ad Combatoral Stochastc Processes, Cambrdge Uversty Press

9 What We Foud s the Power Law The Nature of Mcro Shocks I Stadard Models, Mcro Shocks are Assumed to Wash Out Source : Aoyama H, H. Yoshkawa, H. Iyetom, ad Y. Fuwara (200 Productvty Dsperso : Facts, Theory, ad Implcatos, Joural of Ecoomc Iteracto ad Coordato, Vol.5 We Ca Uderstad Macro by the Average Self-Averagg The Nature of Mcro Shocks Self-Averagg Self-Averagg No Self-Averagg See : Sorette, D (2000, Crtcal Pheomea Natural Sceces, Sprger. x k k CV ( CV ( Varace ( Mea( E( E( E( 2 E( ( E( P(( E( ( E( for ay 0

10 A Smple Growth Model 2 K Y y k y ( 0, a ( 2 Parameter Posso / Drchlet Dstrbuto p p ( 0, 0 k k K a ( exp( l l( y l( Y K a ( No Self-Averagg We Caot Uderstad Macro by the Average Stadard Mcroecoomc Foudatos Based o Represetatve Aget Do ot Make sese See : Aok M. ad H. Yoshkawa, (200 "No-Self-Averagg Macroecoomc Models: A Crtcsm of Moder Mcro-fouded Macroecoomcs", Ceter for Iteratoal Research o the Japaese Ecoomy Dscusso Paper, CIRJE-F-76.

11 Tree Structure Trasto Rates Markov Model (a Three-level Tree (b Oe-level Tree Source : Aok M. ad H. Yoshkawa, (200 "No-Self-Averagg Macroecoomc Models: A Crtcsm of Moder Mcrofouded Macroecoomcs", Ceter for Iteratoal Research o the Japaese Ecoomy Dscusso Paper, CIRJE-F-76. Progress of Macroecoophyscs Requres Close Collaborato of Ecoomsts ad Physcsts