Termination Proofs in the Dependency Pair Framework May Induce Multiple Recursive Derivational Complexity

We study the derivational complexity of rewrite systems whose termination is provable in the dependency pair framework using the processors for reduction pairs, dependency graphs, or the subterm criterion. We show that the derivational complexity of such systems is bounded by a multiple recursive function, provided the derivational complexity induced by the employed base techniques is at most multiple recursive. Moreover we show that this upper bound is tight.Comment: 22 pages, extended conference versio

A Vicious Cycle of Manias, Crashes and Asymmetric Policy Responses - An Overinvestment View

The business cycles theories of Wicksell (1898), Schumpeter (1912), Mises (1912), Hayek (1929, 1935) and Minsky (1986, 1992) explain business cycles by distorted prices on capital markets, buoyant credit expansion and overinvestment. The exuberance during the boom endogenously causes the subsequent slump. While these theories put the emphasis on explaining the emergence of the cycle, this paper focuses on the macroeconomic policy responses during and after the crisis, when panic tightens credit supply. The paper allows an assessment of the long-term consequences of an asymmetric monetary and fiscal policy response to financial crisis.

A Vicious Cycle of Manias, Crashes and Asymmetric Policy Responses - An Overinvestment View

The business cycles theories of Wicksell (1898), Schumpeter (1912), Mises (1912), Hayek (1929, 1935) and Minsky (1986, 1992) explain business cycles by distorted prices on capital markets, buoyant credit expansion and overinvestment. The exuberance during the boom endogenously causes the subsequent slump. While these theories put the emphasis on explaining the emergence of the cycle, this paper focuses on the macroeconomic policy responses during and after the crisis, when panic tightens credit supply. The paper allows an assessment of the long-term consequences of an asymmetric monetary and fiscal policy response to financial crisis.Manias; Bubbles; Austrian; Policy Responses

Monetary Policy, Vagabonding Liquidity and Bursting Bubbles in New and Emerging Markets – An Overinvestment View

Credit booms have globally fuelled hikes in stock, raw material and real estate markets which have culminated in the recent US subprime market crisis. We explain the global asset market booms since the mid 1980s based on the overinvestment theories of Hayek, Wicksell and Schumpeter. We argue that ample liquidity supply originating in the large industrialized countries has contributed to overinvestment cycles in Japan, East Asia, the new markets in the industrial countries and many emerging market economies. Expansionary monetary policies in response to the burst of bubbles are argued to have contributed to vagabonding bubbles around the globe.bubbles, boom-bust cycles, Hayek, Wicksell, Schumpeter, emerging markets, capital flows, overinvestment theories

The theory of optimum currency areas and growth in emerging markets

We test for the impact of exchange rate volatility on growth in emerging market economies based on the theory of optimum currency areas. Our findings provide evidence for a positive impact of exchange rate stability on growth. --OCA,growth

Symmetrische Regeln und asymmetrisches Handeln in der Geld- und Finanzpolitik

Das Papier untersucht auf der Grundlage der monetären Überinvestitionstheorien von Wicksell (1898), Mises (1912) and Hayek (1929, 1935) das Scheitern von geld- und finanzpolitischen Regeln zur Kontrolle von übermäßigem Geldmengenwachstum und ausufernder Staatsverschuldung. Es zeigt asymmetrische Geld- und Finanzpolitiken in den großen Industrieländern auf, die zu einem Verfall der Geldmarktzinsen gegen Null und einem Anstieg der Staatsverschuldungen auf globale Rekordstände geführt haben. Das strukturelle Absinken des globalen Zinsniveaus wird als Ursache für globale Überinvestitions- bzw. Boom-und-Krisen-Zyklen gesehen, die zu einem Ausufern der Staatsverschuldung geführt haben. Zur Stabilisierung des langfristigen globalen Wachstums wird die Rückkehr zu symmetrischen Regeln in der Geld- und Finanzpolitik gefordert. --Regeln,Geldpolitik,Finanzpolitik,Asymmetrie,Boom-und-Krisen-Zyklen,Exit

The exact hardness of deciding derivational and runtime complexity

For any class C of computable total functions satisfying some mild conditions, we prove that the following decision problems are complete for the existential part of the second level of the arithmetical hierarchy: (A) Deciding whether a term rewriting system (TRS for short) has runtime complexity bounded by a function in C. (B) Deciding whether a TRS has derivational complexity bounded by a function in C. In particular, the problems of deciding whether a TRS has polynomially (exponentially) bounded runtime complexity (respectively derivational complexity) are complete for this level of the arithmetical ierarchy. This places deciding polynomial derivational or runtime complexity of TRSs at the same level as deciding nontermination or nonconfluence of TRSs. We proceed to show that the related problem of deciding for a single computable function f whether a TRS has runtime complexity bounded from above by f is complete for the universal part of the first level of the arithmetical hierarchy. We further prove that analysing the implicit complexity of TRSs is even more difficult: The problem of deciding whether a TRS accepts a language of terms accepted by some TRS with runtime complexity bounded by a function in C is complete for the existential part of the third level of the arithmetical hierarchy. All of our results are easily extended to the notion of minimal complexity (where the length of shortest reductions to normal form is considered) and remain valid under any computable reduction strategy. Finally, all results hold both for unrestricted TRSs and for the class of orthogonal TRSs

Geldpolitik, vagabundierende Liquidität und platzende Blasen in neuen aufstrebenden Märkten

Die Ungleichgewichte auf den internationalen Finanzmärkten werden von den Finanzministern und Notenbankchefs der Industrieländer mit zunehmendem Unbehagen betrachtet. In Hinblick auf Hedge-Fonds soll bis zum G-8-Gipfel im Juni dieses Jahres ein Verhaltenskodex erarbeitet werden. Inwieweit können Hedge-Fonds zur Instabilität der Finanzmärkte beitragen? Welche Strategien zur Krisenvermeidung sollten verfolgt werden? Welche Institutionen sollten aktiv werden? --

The Derivational Complexity Induced by the Dependency Pair Method

We study the derivational complexity induced by the dependency pair method, enhanced with standard refinements. We obtain upper bounds on the derivational complexity induced by the dependency pair method in terms of the derivational complexity of the base techniques employed. In particular we show that the derivational complexity induced by the dependency pair method based on some direct technique, possibly refined by argument filtering, the usable rules criterion, or dependency graphs, is primitive recursive in the derivational complexity induced by the direct method. This implies that the derivational complexity induced by a standard application of the dependency pair method based on traditional termination orders like KBO, LPO, and MPO is exactly the same as if those orders were applied as the only termination technique

A Vicious Cycle of Manias, Crashes and Asymmetric Policy Responses - An Overinvestment View

The business cycles theories of Wicksell (1898), Schumpeter (1912), Mises (1912), Hayek (1929, 1935) and Minsky (1986, 1992) explain business cycles by distorted prices on capital markets, buoyant credit expansion and overinvestment. The exuberance during the boom endogenously causes the subsequent slump. While these theories put the emphasis on explaining the emergence of the cycle, this paper focuses on the macroeconomic policy responses during and after the crisis, when panic tightens credit supply. The paper allows an assessment of the long-term consequences of an asymmetric monetary and fiscal policy response to financial crisis