technical trading in the santa fe institute artificial stock market revisited abstract this paper reconsiders evidence of technical trading in the santa fe artificial stock market in light of an upwardly biased mutation operator while an alternative mutation operator points to no technical trading two tests other than the inappropriate investigation of the aggregate bit level establish the existence of technical trading beyond a doubt the following analysis of the two mutation operators identifies genetic drift as an important evolutionary force and provides tools to judge the relative importance of selection and genetic drift with arbitrary mutation operators it also finds that when selective forces are weak the continued existence of technical trading can be reconciled with the efficient market hypothesis

two remarks on the property rights literature we first point out that the recent property rights literature is based on three assumptions 1 that contracts are always subject to renegotiation 2 that the exercise of a property right confers a private benefit and 3 that parties are risk neutral building on hart moore 1999 we provide conditions under which an optimal contract consists of nothing more than an assignment of property rights we also examine the robustness of some of the literature s standard predictions about asset ownership to the introduction of mechanisms for eliciting parties ex post willingness to pay for the assets such as options or financial markets to illustrate the issue we revisit the hart moore 1990 proposition that joint ownership is suboptimal and argue that ownership by a single party is dominated by joint ownership with put options

wealth driven selection in a financial market with heterogeneous agents we study the co evolution of asset prices and individual wealth in a financial market with an arbitrary number of heterogeneous boundedly rational investors using wealth dynamics as a selection device we are able to characterize the long run market outcomes i e asset returns and wealth distributions for a general class of competing investment behaviors our investigation illustrates that market interaction and wealth dynamics pose certain limits on the outcome of agents interactions even within the wilderness of bounded rationality as an application we consider the case of heterogeneous mean variance optimizers and provide insights into the results of the simulation model introduced by levy levy and solomon 1994

aggregate savings financial intermediation and interest rate there has been considerable controversy about the role of financial factors as determinants of savings in developing countries this paper explores the importance of two such factors namely real interest rate and financial intermediation using pooled time series cross section data a model of savings is estimated for asia latin america and for the total sample particular attention is paid to the error structure in estimation the results suggest that pooling is not justified further there is no unequivocal support for the effect of either of the two factors some qualified support is found for asia but none for latin america copyright 1987 by mit press

contractibility and the design of research agreements we analyze how contractibility affects contract design a major concern when designing research agreements is that researchers may use their funding to subsidize other projects we show that when research activities are not contractible an option contract is optimal the financing firm obtains the option to terminate the agreement and in case of termination broad property rights the threat of termination deters researchers from cross subsidization and the cost of exercising the termination option deters the financing firm from opportunistic termination we test this prediction using 580 biotechnology research agreements contracts with termination options are more common when research is non contractible

inflation its variability and consumption in selected latin american countries abstract the aim of this paper is to estimate the impact of inflation on consumer expenditures in argentina brazil and chile attention is also given to the impact of uncertainty about inflation and to the role of liquid assets

how do plural sourcing firms make and buy the impact of supplier portfolio design this paper uses the notion of contracting strategy to advance research on plural sourcing we develop and test a theoretical framework to explain how plural sourcing firms strike the make and buy b

interest rate determination in a small open economy abstract this paper is an attempt to explain the behavior of ex ante real rates of interest in singapore during the period 1961 1981 this is done within a model which explicitly allows for the role of supply shocks inflation uncertainty and foreign interest rates

outsourcing and unionization a tale of misallocated resistance resources while many believe the growth in outsourcing contributed to the decline in u s unionization up to the 1990s this argument has never been investigated systematically in this article we analyze the effect of outsourcing on unionization between 1973 and 1993 instrumental variables estimation shows outsourcing contributes to higher quasirents and industry productivity we find the union wage premium increases with the extent of outsourcing both for workers that are substitutable by outsourcing services and workers in jobs that are not substitutes of the tasks being outsourced finally we find no support for the claim that outsourcing reduces unionization jel j5 l2 l6

vertical integration and firm boundaries the evidence since ronald h coase s 1937 seminal paper a rich set of theories has been developed that deal with firm boundaries in vertical or input output structures in the last twenty five years empirical evidence that can shed light on those theories also has been accumulating we review the findings of empirical studies that have addressed two main interrelated questions first what types of transactions are best brought within the firm and second what are the consequences of vertical integration decisions for economic outcomes such as prices quantities investment and profits throughout we highlight areas of potential cross fertilization and promising areas for future work

asset price and wealth dynamics in a financial market with heterogeneous agents abstract this paper considers a discrete time model of a financial market with one risky asset and one risk free asset where the asset price and wealth dynamics are determined by the interaction of two groups of agents fundamentalists and chartists in each period each group allocates its wealth between the risky asset and the safe asset according to myopic expected utility maximization but the two groups have heterogeneous beliefs about the price change over the next period the chartists are trend extrapolators while the fundamentalists expect that the price will return to the fundamental we assume that investors optimal demand for the risky asset depends on wealth as a result of crra utility a market maker is assumed to adjust the market price at the end of each trading period based on excess demand and on changes of the underlying reference price the model results in a nonlinear discrete time dynamical system with growing price and wealth processes but it is reduced to a stationary system in terms of asset returns and wealth shares of the two groups it is shown that the long run market dynamics are highly dependent on the parameters which characterize agents behaviour as well as on the initial condition moreover for wide ranges of the parameters a locally stable fundamental steady state coexists with a stable non fundamental steady state or with a stable closed orbit where only chartists survive in the long run such cases require the numerical and graphical investigation of the basins of attraction other dynamic scenarios include periodic orbits and more complex attractors where in general both types of agents survive in the long run with time varying wealth fractions

stock market crashes as social phase transitions abstract stock market crashes are traumatic events that affect the lives of millions of people around the globe and have tremendous economic implications crashes are not only dramatic but often completely unexpected the 1987 crash for example was not induced by any obvious trigger even after the fact it is hard to find the reason for the crash why did the market crash in october rather than in september or december why did it crash at all to this day we lack satisfactory answers this paper shows that spontaneous market crashes can be explained by a social phase transition mechanism similar to statistical mechanics phase transitions investors heterogeneity plays the role of temperature and is key in determining the possibility and magnitude of the crash the analysis suggests that dramatic crashes are a robust and inevitable property of financial markets it also implies that market crashes should be preceded by an increase in price volatility as empirically observed thus market crashes like earthquakes are a fundamental and unavoidable part of our world however we can develop early warning systems that may help minimize the damage

relational incentive contracts standard incentive theory models provide a rich framework for studying informational problems but assume that contracts can be perfectly enforced this paper studies the design of self enforced relational contracts i show that optimal contracts often can take a simple stationary form but that self enforcement restricts promised compensation and affects incentive provision with hidden information it may be optimal for an agent to supply the same inefficient effort regardless of cost conditions with moral hazard optimal contracts involve just two levels of compensation this is true even if performance measures are subjective in which case optimal contracts terminate following poor performance jel c73 d82 l14

endogenous matching and the empirical determinants of contract form empirical work on contracts typically regresses contract choice on observed principal and agent characteristics if i some of these characteristics are unobserved or partially observed and ii there are incentives whereby particular types of agents end up contracting with particular types of principals estimated coefficients on the observed characteristics may be misleading we address this endogenous matching problem using a data set on agricultural contracts between landlords and tenants in early renaissance tuscany controlling for endogenous matching has an impact on parameters of interest and tenants risk aversion appears to have influenced contract choice

money as a medium of exchange in an economy with artificially intelligent agents abstract we study the exchange economies of kiyotaki and wright 1989 in which agents must use a commodity or fiat money as a medium of exchange if trade is to occur our agents are artificially intelligent and are modeled as using classifier systems to make decisions in the assignment of credit within the classifier systems we introduce some innovations designed to study sequential decision problems in a multi agent environment for most economies that we have simulated trading and consumption patterns converge to a stationary nash equilibrium even if agents start with random rules in economies with multiple equilibria the only equilibrium that emerges in our simulations is the one in which goods with low storage costs play the role of medium of exchange i e the fundamental equilibrium of kiyotaki and wright

on money as a medium of exchange we analyze economies in which individuals specialize in consumption and production and meet randomly over time in a way that implies that trade must be bilateral and quid pro quo nash equilibria in trading strategies are characterized certain goods emerge endogenously as media of exchange or commodity money depending both on their intrinsic properties and on extrinsic beliefs there are also equilibria with genuine fiat currency circulating as the general medium of exchange we find that equilibria are not generally pareto optimal and that introducing fiat currency into a commodity money economy may unambiguously improve welfare velocity acceptability and liquidity are discussed

fisher phillips friedman and the measured impact of inflation on interest a reply the purpose of this paper is to demonstrate that empirical findings which persistently appear to contradict the fisher hypothesis that the nominal rate of interest should rise by the full amount of an increase in anticipated inflation are due basically to a failure to control for changes in the real rate of interest that are associated with changes in anticipated inflation we are guided in our search for proper specification of a fisher equation by a simple general equilibrium model which is employed to derive the impact of a change in anticipated inflation upon nominal interest given the requirement that commodity money and labor markets remain in equilibrium in effect we depart from the empirical tradition which has grown up around testing of the fisher hypothesis that takes the real interest rate to be independent of anticipated inflation and argues that for anticipated inflation properly measured the data ought to support the fisher hypothesis 1

the effects of inflation uncertainty and supply shocks on real interest rates abstract increased inflation uncertainty and negative supply shocks have been suggested separately as causes of the 1970s decline in real interest rates when both factors appear in empirical interest rate models supply forces exert a statistically significant impact on real rates while the effect of inflation uncertainty is insignificant

viewpoint empirical research on firms boundaries empirical research on the determinants of firms boundaries has flourished over the past 25 years this article discusses the progress that has been made to date emphasizing the intellectual advances made by researchers in this literature during this period i stress empirical researchers important role in operationalizing theoretical concepts and relate how success on this dimension brings these concepts to bear on real life make or buy decisions i also discuss shortcomings in the current literature in particular the paucity of research on how variation in firms boundaries can affect economic outcomes and point to how and where such shortcomings might be overcome la recherche empirique sur les determinants des frontieres de l entreprise a fleuri au cours des derniers 25 ans cet article discute des progres accomplis en mettant l accent sur les avancees intellectuelles faites par les chercheurs dans la litterature specialisee durant cette periode on souligne le role important des chercheurs empiriques dans l operationnalisation des concepts theoriques et on explique comment les succes dans ce registre ont contribuea faire que ces concepts ont eu un impact sur les decisions de faire ou faire faire dans la vie reelle on discute aussi des deficiences de cette litterature en particulier la pauvrete des travaux de recherche sur l impact de la variation dans les frontieres des entreprises sur les rendements economiques et on suggere comment de telles deficiences pourraient etre corrigees

application specific r d capabilities and the advantage of incumbents evidence from the anticancer drug market this paper examines the proposition that during competence destroying technological changes incumbents are incompetent in researching in house a radically new technology they only retain market leadership if their undestroyed proprietary complementary assets compensate for their research incompetence in contrast to prior research i propose that there is not one but two sets of capabilities necessary to execute research and development r d sets that differ in their market specificity a technology specific set i e technological platforms that are non market specific and an application specific set i e knowledge of the application that is therefore market specific although all markets require both sets of capabilities to execute r d prior research has analyzed cases where the application was not as complex and therefore application specific capabilities did not represent strategic factors because at the start of a technological discontinuity application specific capabilities are undestroyed and have accrued only to incumbents when complex enough these capabilities can represent a source of competitive advantage for these firms even in the face of competition from diversifying entrants reusing previously acquired technological platforms i find evidence consistent with my proposition based on data on outcomes from drug discovery as estimated through clinical endpoints in phase i trials for firms competing in the anticancer drug market one of the most complex markets within pharmaceuticals as the market transitions into the biotechnology revolution the proposition in this paper implies that although technological platforms can help firms move across markets application specific r d capabilities can help firms retain leadership within a market across technological discontinuities

four formal izable theories of the firm in this essay i define and compare elemental versions of four theories of the firm these elemental theories are distilled from important contributions by hart holmstrom klein williamson and others although these contributions have been widely cited and much discussed i have found it difficult to understand the commonalities distinctions and potential combinations of these seemingly familiar contributions in this essay therefore i attempt to clarify these issues in three steps i begin with informal summaries of the theories then turn to simple but formal statements of each elemental theory and finally nest the four elemental theories in an integrative framework

capturing knowledge within and across firm boundaries evidence from clinical development how do firm boundaries influence employees acquisition of information using detailed project level data and qualitative evidence i document that pharmaceutical firms are more likely to outsource the coordination of data intensive clinical trials while they are more likely to assign knowledge intensive trials to internal teams managers do not choose between market and hierarchy but between the hierarchy of the firm in which subjective performance evaluations are combined with flat explicit incentives and the hierarchy of its subcontractor whose virtue stems precisely from the ability to provide high powered incentives on a narrow set

why real interest rates were so low in the 1970 s the economic turmoil of the 1970 s resulted in record postwar increases in inflation unemployment and nominal interest rates yet it was declines that were hardest to explain the average real value of a share of common stock plummeted productivity growth evaporated real interest rates measured as the spread between nominal interest rates and the inflation rate turned negative see table 1 over the past decade an explosion has occurred in the amount of attention paid to the relationship between nominal and thus real interest rates and expected inflation rates a good deal of this effort has been directed toward empirical analysis of the fisher neutrality hypothesis that nominal rates respond one for one with expected inflation rates most empirical tests of the fisher hypothesis have been bivariate interest rates were regressed on a constant and on actual or expected inflation measures estimates of the impact of inflation on interest rates in these and even in extended models are often significantly below one are often statistically imprecise and tend to be unstable over time the middle column of table i reflects this the coefficient of inflation on nominal interest rates there drops from 0 78 to 0 59 in the latter 1970 s another branch of work on nominal interest rates has concentrated on the institutional impediments to the fisher hypothesis robert mundell and james tobin demonstrate that nominal rates change by a smaller amount than the expected inflation rate does when a real balance effect exists and money pays no interest michael darby and martin feldstein on the other hand argue that nominal rates should exhibit a greater thanunity response to expected inflation due to the nature of u s income tax laws 2 here i estimate the relation between interest rates expected inflation and real forces such estimates are required for evaluating the effects of inflation on saving investment the distribution of income and the redistribution of wealth to generate estimates of the net impact of these various factors on interest rates and to avoid the identification and simultaneity problems masked but not often remedied by instrumental variables techniques i employ only exogenous regressors to buttress the argument i examine the individual links in the chain which are summarized in the reduced form the novel aspect of the model presented in section i is its addition of aggregate supply shocks to the determination of interest rates i trace the reduction in the supply of complementary factor inputs in the 1970 s to a decline in the demand for capital and therefore in real interest rates the inclusion of this supply force along with expected inflation allows one to distinguish between two offsetting effects on interest rates the depressing effect on real rates through lower investment demand and the elevating effect on nominal rates of higher expected inflation the results in section ii not only strongly support the economic and statistical importance of supply shocks on real interest rates but also resolve some longstanding interest rate puzzles allowing for the impact of factor supply produces a significant estimated response to expected inflation for a sample that ends prior to late 1960 s the magnitude assistant professor school of business administration university of california berkeley i would like to thank george akerlof robert j gordon robert a meyer joe peek janet yellen the members of the economic analysis and policy seminar at berkeley participants at the nber conference on inflation and financial markets and anonymous referees for helpful comments data resources supplied data and computational services financial support was provided by the berkeley program in finance and nsf grant ses8109093 linda pacheco supplied able research assistance errors of omission or commission are my responsibility see william gibson david pyle john carlson and thomas cargill and robert meyer 2maurice levi and john makin derive the reducedform effect of expected inflation on nominal interest rates as a function of the structural parameters

learning with misspecification in an artificial currency market abstract agents evolve their forecast rules over time via a modified genetic algorithm in a simple artificial currency market these forecast rules can be nonlinearly misspecified when the misspecification is suppressed learning tends to be complete when it is not suppressed learning can generate persistent exchange rate dynamics

time variation of higher moments in a financial market with heterogeneous agents an analytical approach a growing body of recent literature allows for heterogenous trading strategies and limited rationality of agents in behavioral models of financial markets more and more this literature has been concerned with the explanation of some of the stylized facts of financial markets it now seems that some previously mysterious time series characteristics like fat tails of returns and temporal dependence of volatility can be observed in many of these models as macroscopic patterns resulting from the interaction among different groups of speculative traders however most of the available evidence stems from simulation studies of relatively complicated models which do not allow for analytical solutions in this paper this line of research is supplemented by analytical solutions of a simple variant of the seminal herding model introduced by kirman 1993 embedding the herding framework into a simple equilibrium asset pricing model we are able to derive closed form solutions for the time variation of higher moments as well as related quantities of interest enabling us to spell out under what circumstances the model gives rise to realistic behavior of the resulting time series

a microscopic model of the stock market cycles booms and crashes abstract we present a model of the stock market based on the behavior of individual investors simulations exhibit rich phenomena which include cycles booms and crashes low dividend yield and more homogeneous market participants are shown to induce crashes

can a firm find the balance between openness and secrecy towards a theory of an optimum level of disclosure the purpose of this article is not merely to counter assertions about technology leakage spillovers being innocuous or benevolent but to go further and illuminate an under researched question how can companies seek the optimum balance between conscious disclosure and secrecy the article works towards a theory of optimum disclosure by identifying possible benefits and costs of disclosure or openness in paradigm 1 most companies find the net benefits of disclosure openness to be negative in paradigm 2 applicable to a few highly networked or open source mnes there could be net benefits over a limited range and up to an optimum point

stock market crashes and dynamics of aftershocks abstract we begin with the intuitive observation that short term business as usual process and bubble rising looks like an accelerated energy before an earthquake in such a framework the aftershocks resemble the correction process of the stock market we investigate the statistical properties of stock returns in the financial markets just after a major market crash it is found that the aftershocks obey the well known gutenberg richter simple rule in geophysics our empirical observations show that the statistical properties of aftershocks sequences in the crashes of late 90s and early 00s are essentially different from the ones observed a decade earlier

an operational measure of liquidity embedding the process of selling an asset in a search environment enables one to provide an exact definition of liquidity an asset s liquidity is the expected time until it is sold while pursuing an optimal in the sense of maximization of expected discounted net proceeds policy this analysis reveals that this definition is compatible with most other notions of liquidity and in particular with those of john maynard keynes impatience the discount associatedwith a quick sale predictability and flexibility copyright 1986 by american economic association

market liquidity hedging and crashes in the absence of significant news hedging strategies were blamed for the stock market crash of october 1987 but traditional models cannot explain how a relatively small amount of selling could cause so large a price drop the authors develop a rational expectations model in which prices play an important role in shaping expectations markets are much less liquid in their model than in traditional models discontinuities or crashes can occur even with relatively little hedging the model is consistent with theories as disparate as keynes beauty contest insights and thom s catastrophe analysis and suggests means to reduce volatility copyright 1990 by american economic association

effects of price signal choices on market stability using simulation and analysis we show that agent based auction cleared automated markets can be stabilized using only completely myopic agents without value traders if these na ove agents are provided with a price signal that reflects order book information this demonstrates that information in the order book is extremely valuable that prediction can be replaced by better instantaneous information about others bids and suggests new more stable algorithms for market based control 2003 elsevier science b v all rights reserved