bulls bears and market sheep abstract a deterministic excess demand model of stock market behavior is presented that generates stochastically fluctuating prices and randomly switching bear and bull markets

garch inadequacy for modelling exchange rates empirical evidence from latin america this article checks for the adequacy of using garch models in exchange rate series using the hinich portmanteau bicorrelation test we find that a garch formulation or any of its variants fails to capture the data generating process of the main latin american exchange rates our results highlight the potential of having misleading public policy when estimates are based in garch types of models this article also complements recent similar findings encountered in european and asian economies

nonrenewable resource scarcity nonrenewable resource theory often is summarized by hotelling s rule this paper reviews theoretical extensions and empirical investigations of resource extraction models observed data are often inconsistent with the hotelling rule suggesting that other characteristics of nonrenewable resource supply including exploration heterogeneous ore quality technological progress and capital investment are important determinants of the dynamic behavior of resource prices given the persistent recurrence of concern about nonrenewable resource scarcity measures of nonrenewable resource scarcity and the empirical evidence for the time trends of those measures are reviewed finally the implications of nonrenewable resource scarcity for economic growth are examined

chaos in oil prices evidence from futures markets abstract we test for the presence of low dimensional chaotic structure in crude oil heating oil and unleaded gasoline futures prices from the early 1980s evidence on chaos will have important implications for regulators and short term trading strategies while we find strong evidence of non linear dependencies the evidence is not consistent with chaos our test results indicate that arch type processes with controls for seasonal variation in prices generally explain the non linearities in the data we also demonstrate that employing seasonally adjusted price series contributes to obtaining robust results via the existing tests for chaotic structure maximum likelihood methodologies that are robust to the non linear dynamics lend support for samuelson s hypothesis on contract maturity effects in futures price changes however the tests for chaos are not found to be sensitive to the maturity effects in the futures contracts the results are robust to controls for the oil shocks of 1986 and 1991

uncovering nonlinear structure in real time stock market indexes the s p 500 the dax the nikkei 225 and the ftse 100 this article tests for nonlinear dependence and chaos in real time returns on the world s four most important stock market indexes both the brock dechert scheinkman and the lee white and granger neural network based tests indicate persistent nonlinear structure in the series estimates of the lyapunov exponents using the nychka ellner gallant and mccaffrey neural net method and the zeng pielke and eyckholt nearest neighbor algorithm confirm the presence of nonlinear dependence in the returns on all indexes but provide no evidence of low dimensional chaotic processes given the sensitivity of the results to the estimation parameters we conclude that the data are dominated by a stochastic component

oil price volatility and stock price fluctuations in an emerging market evidence from south korea abstract how important are oil price fluctuations and oil price volatility on equity market performance what are the policy implications if volatility turns out to be significant we assess this issue in an economics finance nexus for korea using a vec model including interest rates economic activity real stock returns real oil prices and oil price volatility our main aim is to capture the effects of crude oil prices on the korean economy thoroughly covering the period of the asian financial crisis of 1997 which heavily affected the country and the oil price hikes in the early 1990s after the gulf war south korea was the country most hit by the financial crisis together with indonesia and thailand results indicate the dominance of oil price volatility on real stock returns and emphasize how this has increased over time oil price volatility can have profound effect on the time horizon of investment and firms need adjust their risk management procedures accordingly this increase in dependency has been found in other net oil importing emerging equity markets we test the relationship between oil price movements and economic activity by using modern time series techniques in a cointegrating framework we expand the standard error correction model by examining the dynamics of out of sample causality through the generalized variance decomposition and impulse response function techniques the evidence from persistence profiles also gives important guidelines based on how fast the entire system adjusts back to equilibrium in addition we find the cointegrating relationship to be stable and find that the linear error correction model to be more favorable than an asymmetric 2 period markov switching model

a characterization of erratic dynamics in the overlapping generations model abstract in this paper we characterize and give examples o wide classes of utility functions which generate erratic dynamics in the standard deterministic overlapping generations model erratic dynamics refers to feasible trajectories which are bounded but which do not converge to stationary points or periodic orbits we show that such trajectories are pareto efficient we introduce credit into the model and show how a constant credit expansion rate can result in erratic trajectories in prices and the real value of credit finally we briefly discuss certain technical aspects of the mathematics used and the statistical nature of the dynamics that can arise from deterministic dynamical systems

testing for nonlinear dependence in daily foreign exchange rates the purpose of this article is to investigate whether daily changes in five major foreign exchange rates contain any nonlinearities although the data contain no linear correlation evidence indicates the presence of substantial nonlinearity in a multiplicative rather than additive form further examination reveals that a generalized autoregressive conditional heteroskedasticity model can explain a large part of the nonlinearities for all five exchange rates copyright 1989 by the university of chicago

the behavior of foreign exchange rates the analysis of the distribution of foreign exchange rate changes provides a description of the behavior of foreign exchange rates and its determining underlying process the application of empirical methodologies or further theoretical developments is limited by the nature of this distribution in this paper the empirical analysis of major currencies during the flexible exchange rate period suggests that there is no unique distribution representing the behavior of the foreign exchange rate this however is determined both by foreign exchange management policies and the fundamental economic forces

crude oil corn ethanol nexus a contextual approach this paper offers a holistic study on the complex relationships between crude oil corn and ethanol during a turbulent period between 2006 and end of 2011 through a holistic mapping of the current market situation and a contextual analytical design we show that there exists a strong relationship between crude oil and corn markets on one side and crude oil and ethanol on the other however the price relationship between corn and ethanol was revealed to be less straightforward and is driven by the us government fuel policy furthermore the study indicates that corn markets have became more prone to volatility due to ethanol production especially when the demand for corn is high and or the crude oil prices are high enough to create a competitive market for ethanol

efficiency analysis for exogenously fixed inputs and outputs we evaluate by means of mathematical programming formulations the relative technical and scale efficiencies of decision making units dmus when some of the inputs or outputs are exogenously fixed and beyond the discretionary control of dmu managers this approach further develops the work on efficiency evaluation and on estimation of efficient production frontiers known as data envelopment analysis dea we also employ the model to provide efficient input and output targets for dmu managers in a way that specifically accounts for the fixed nature of some of the inputs or outputs we illustrate the approach using real data for a network of fast food restaurants

budget constrained frontier measures of fiscal equality and efficiency in schooling equality and efficiency are key issues in educational reform here the authors analyze the efficiency and equality consequences of various school finance reforms using a cost indirect output distance function this function readily models multiple output production under conditions of budgetary constraint and provides a natural measure of performance that is closely related to farrell type measures of efficiency the analysis suggests that despite school district inefficiency finance reforms can affect student achievement however any potential gains in output from redistribution are dwarfed by the potential gains from increased efficiency more strikingly the analysis demonstrates that budgetary reforms designed to equalize expenditures could actually increase the inequality of student achievement

nonlinear monetary dynamics this article uses the correlation dimension technique along with the residual and shuffle tests to look for evidence of nonlinear dynamic structure in various weekly monetary aggregates their components the monetary base and the money multipliers the results support the barnett and chen 1988 and chen 1988 findings of nonlinearity in divisia m2 divisia m3 and simple sum m2 evidence of nonlinear structure is also found for simple sum m1 currency demand deposits all checkable deposits m3 minus m2 the monetary base and the multipliers of m1 m2 and m3

episodic nonlinearity and nonstationarity in alberta s power and natural gas markets abstract this paper uses a new method of testing for linear and nonlinear lead lag relationships between time series introduced by brooks and hinich brooks c and hinich m j cross correlations and cross bicorrelations in sterling exchange rates journal of empirical finance 20 1999 385 404 on alberta s natural gas and power markets the test based on the concepts of cross correlation and cross bicorrelation is used after pre whitening of the data to test for the existence of residual nonlinearity as well as the episodic nature of the nonlinearity our evidence points to a relatively rare episodic nonlinearity within and across the two series having important implications for forecasting these series

application of nonlinear mapping theory to commodity price fluctuatuions abstract the cobweb model of price stability with lagged price elasticities is extended to include nonlinear terms the result falls within nonlinear mapping models such as the logistics map nonlinearities prevent the unbounded oscillation predicted from the unstable linear cobweb but the price time series may exhibit chaotic unpredictable endogenous fluctuations the theory is applied to the u s crude oil market regressing consumption against price gives lagged elasticities greater than current elasticities indicating linear instability this instability is seen in a mapping model of the price time series predictions of the model are given both with and without nonlinear terms indicating large continuing endogenous price fluctuations

the distribution of foreign exchange price changes trading day effects and risk measurement a comment in their 1982 study mcfarland pettit and sung 16 mps found that consecutive daily foreign exchange rates conform to neither a normal nor a nonnormal stable process and that day of the week data could be adequately described by a series of different stable distributions the authors have also documented a weekday effect in the foreign exchange market mondays and wednesdays offered higher average price changes than did thursdays and fridays in a more recent study jaffe and westerfield 9 documented negative monday returns for the currencies of the u k canada and australia in estimating the parameters of the distribution mps have utilized the fama and roll 5 6 method which assumes a symmetric distribution jaffe and westerfield 9 report only estimates of the sample moments the sample moments reported in mps s table ii part of which is reproduced in table i here reveal that most currencies especially the minor currencies the australian dollar the spanish peseta and the swedish krona have significant skewness the results indicate that the asymmetric stable paretian distribution may be more appropriate for the overall daily returns this hypothesis is consistent with

distinguishing between stochastic and deterministic behavior in foreign exchange rate returns further evidence abstract the nature of non linear dependence in hourly exchange rate returns is scrutinized while the brock dechert and scheinkman bds test results reject i i d behavior various correlation dimension estimates reveal little evidence in favor of a low dimensional attractor in the time series

complexity and the character of stock returns empirical evidence and a model of asset prices based on complex investor learning empirical evidence on the distributional characteristics of common stock returns indicates 1 a power law tail index close to three describes the behavior of the positive tail of the survivor function of returns pr r x x a reflection of fat tails 2 general linear and nonlinear dependencies exist in the time series of returns 3 the time series return process is characterized by short run dependence short memory in both returns as well as their volatility the latter usually characterized in the form of autoregressive conditional heteroskedasticity and 4 the time series return process probably does not exhibit long memory but the squared returns process does exhibit long memory we propose a model of complex self referential learning and reasoning amongst economic agents that jointly produces security returns consistent with these general observed facts and which are supported here by empirical results presented for a benchmark sample of 50 stocks traded on the new york stock exchange the market we postulate is populated by traders who reason inductively while compressing information into a few fuzzy notions that they can in turn process and analyze with fuzzy logic we analyze the implications of such behavior for the returns on risky securities within the context of an artificial stock market model dynamic simulation experiments of the market are conducted from which market clearing prices emerge allowing us to then compute realized returns we test the effects of varying values of the parameters of the model on the character of the simulated returns the results indicate that the model proposed in this paper can jointly account for the presence of a power law characterization of the positive tail of the survivor function of returns with exponent on the order of three for autoregressive conditional heteroskedasticity for long memory in volatility and for general nonlinear dependencies in returns

efficiency and equity in private and public education a nonparametric comparison we present a nonparametric approach for 1 efficiency and 2 equity evaluation in education firstly we use a nonparametric data envelopment analysis model that is specially tailored to assess educational efficiency at the pupil level the model accounts for the fact that typically minimal prior structure is available for the behavior objectives and feasibility set under evaluation it allows for uncertainty in the data while it corrects for exogenous environmental characteristics that are specific to each pupil secondly we propose two multidimensional stochastic dominance criteria as naturally complementary aggregation criteria for comparing the performance of different school types private and public schools while the first criterion only accounts for efficiency the second criterion also takes equity into consideration the model is applied for comparing private but publicly funded and public primary schools in flanders our application finds that no school type robustly dominates another type when controlling for the school environment and taking equity into account more generally it demonstrates the usefulness of our nonparametric approach which includes environmental and equity considerations for obtaining fair performance comparisons in the public sector context

tick size the compass rose and market nanostructure abstract economists have begun using methods borrowed from the physical sciences to search for non linearities in economic and financial data the so called phase portrait from chaos theory in which the values of a time series are plotted against their delayed values is one of the techniques employed for this purpose it has recently been shown however that when returns on traded assets are plotted in this manner in two or three dimensional space surprising patterns arise which seriously distort the conclusions that can be drawn about the underlying data these patterns which resemble a compass rose reflect the microstructure of the market or more specifically the finite size of the ticks by which prices can change in a market the present paper clarifies the reason for this phenomenon it is shown that within the microstructure there exists nanostructure that becomes visible only when the computations are performed without approximation high frequency data from a foreign exchange market are used to illustrate this phenomenon

the distribution of foreign exchange price changes trading day effects and risk measurement this study investigates the nature of price changes in a variety of major and minor foreign exchange markets the results suggest that the log of price changes over one trading day intervals seems to follow a non normal stable distribution function different measures of location and to lesser extent scale are present for different days of the week dollar denominated price changes are high on mondays and wednesdays and low on thursdays and fridays for all currencies the wednesday thursday result is consistent with the settlement procedures used in foreign exchange transactions in the dollar the friday monday result is consistent with an increase in demand for the dollar prior to the weekend this study offers some previously unavailable results on the nature of price changes in a certain set of speculative markets in particular this is a study of the distributional characteristics of daily and weekly price changes for a number of major and minor foreign exchange markets the results document the existence of non normal stable distributions for price changes in foreign exchange markets these price change distributions differ by day of the week in ways that are only partly attributable to the institutional structure of the market the results of the study are interpreted within the context of understanding how foreign exchange markets operate and within the context of prior studies of stock market data concerned with summarizing the probability distribution of price changes for different intervals including days of the week since bachelier s 1 original treatise that contained the proposition that speculative market prices follow a process that could be described by a normal distribution there have been numerous alternative attempts to describe the stochastic processes which characterize speculative market prices these studies have not resulted in any generalized description of the probability distribution of price changes in such markets indeed the evidence suggests substantial differences in the process among various types of financial instruments the failure to achieve consensus can be traced to the lack of robustness in the statistical procedures employed to estimate processes and to differences in the underlying institutional or economic arrangements which are unique to that market the possibility of differences in the information set used to assess value or differences in technology for transmitting information makes it important to secure additional

nonparametric modeling of carbon prices this paper constitutes the first exercise of nonparametric modeling applied to carbon markets the framework of analysis is carefully detailed and the empirical application unfolds in the case of bluenext spot and ecx futures prices the data is gathered in daily frequency from april 2005 to april 2010 first we document the presence of strong nonlinearities in the conditional mean functions second the conditional volatility functions reveal an asymmetric and heteroskedastic behavior which is dramatically different between carbon spot and futures logreturns the results for spot prices are also robust to subsamples decomposition third we show in an out of sample forecasting exercise that nonparametric modeling allows reducing the prediction error by almost 15 compared to linear ar models this latter result is confirmed by the diebold mariano pairwise test statistic

efficient resource allocation via efficiency bootstraps an application to r d project budgeting resource allocation decisions are crucial for the success of an organization this paper proposes an integrated approach to resource allocation problems in which decision makers have one observation of the multiple input output criteria of candidates we offer important improvements over existing approaches based on the widely used data envelopment analysis dea which has two major limitations in its application to resource allocation first traditional dea models compute efficiency scores by optimizing firm specific shadow prices of inputs and outputs this could be problematic because in practice stakeholders would usually require unanimously agreed upon trade offs among evaluation criteria second previous allocation approaches based on dea do not allow for controlling the risk exposure of allocation portfolios to tackle these problems we propose an efficiency measure based on equilibrium shadow prices of different criteria and we use the bootstrap efficiency distributions to gather information regarding efficiency variations and correlations through our methodology decision makers can obtain the risk minimizing allocation portfolio we illustrate the proposed approach through an empirical r d project budgeting problem in which we allocate funding according to the projects efficiency distributions

testing for non linear structure in an artificial financial market abstract we present a stochastic simulation model of a prototype financial market our market is populated by both noise traders and fundamentalist speculators the dynamics covers switches in the prevailing mood among noise traders optimistic or pessimistic as well as switches of agents between the noise trader and fundamentalist group in response to observed differences in profits the particular behavioral variant adopted by an agent also determines his decision to enter on the long or short side of the market short run imbalances between demand and supply lead to price adjustments by a market maker or auctioneer in the usual walrasian manner our interest in this paper is in exploring the behavior of the model when testing for the presence of chaos or non linearity in the simulated data as it turns out attempts to determine the fractal dimension of the underlying process give unsatisfactory results in that we experience a lack of convergence of the estimate explicit tests for non linearity and dependence the bds and kaplan tests also give very unstable results in that both acceptance and strong rejection of iidness can be found in different realizations of our model all in all this behavior is very similar to experience collected with empirical data and our results may point towards an explanation of why robustness of inference in this area is low however when testing for dependence in second moments and estimating garch models the results appear much more robust and the chosen garch specification closely resembles the typical outcome of empirical studies

a class of nonlinear arch models a class of nonlinear arch models is suggested the proposed class encompasses several functional forms for arch which have been put forth in the literature a lagrange multiplier test is developed to test engle s arch specification against the wider class of models this test provides an easily computed diagnostic check of the adequacy of an arch model after it has been estimated the theory is applied to a number of weekly exchange rate series and we find strong evidence of nonlinear arch

operational research in education operational research or techniques have been applied from the early stages of the discipline to a wide variety of issues in education at the government level these include questions of what resources should be allocated to education as a whole and how these should be divided amongst the individual sectors of education and the institutions within the sectors another pertinent issue concerns the efficient operation of institutions how to measure it and whether resource allocation can be used to incentivise efficiency savings local governments as well as being concerned with issues of resource allocation may also need to make decisions regarding for example the creation and location of new institutions or closure of existing ones as well as the day to day logistics of getting pupils to schools issues of concern for managers within schools and colleges include allocating the budgets scheduling lessons and the assignment of students to courses this survey provides an overview of the diverse problems faced by government managers and consumers of education and the or techniques which have typically been applied in an effort to improve operations and provide solutions

forecasting volatility of crude oil markets abstract this article investigates the efficacy of a volatility model for three crude oil markets brent dubai and west texas intermediate wti with regard to its ability to forecast and identify volatility stylized facts in particular volatility persistence or long memory in this context we assess persistence in the volatility of the three crude oil prices using conditional volatility models the cgarch and figarch models are better equipped to capture persistence than are the garch and igarch models the cgarch and figarch models also provide superior performance in out of sample volatility forecasts we conclude that the cgarch and figarch models are useful for modeling and forecasting persistence in the volatility of crude oil prices

on the determinants of school district efficiency competition and monitoring abstract a number of researchers have asserted that inefficiency in the u s school system arises from a lack of incentives for public schools to behave efficiently this paper uses a shephard input distance function to model educational production and a switching regressions estimation to explore the relationship between school district efficiency and two existing incentive mechanisms competition and voter monitoring we find evidence that ease of monitoring enhances both technical and allocative efficiency of urban school districts and that increased competition reduces allocative inefficiency in communities above a competitive threshold we find no evidence that competition is related to technical inefficiency

chaos and the compass rose abstract we show that the recently discovered compass pattern in stock returns that results from discrete jumps of stocks seriously distorts the null distribution of the brock dechert scheinkmann bds chaos test under the null hypothesis of i i d returns the true rejection probability exceeds the nominal size by wide margins which suggests that much of the evidence for chaos that has so far been found in stock returns might well be due to the fact that prices change only in discrete ticks

nonlinear dependence in finnish stock returns abstract past research into the evolution of finnish stock returns focuses on modeling linear and nonlinear dependence using various arima and garch formulations respectively this paper extends the extant work by using grassberger procaccia correlations dimensions to explore the nature of the nonlinear dynamics in daily finnish stock returns during the 1970s and 1980s nonlinear behavior in both periods is evident a simple garch model removes the nonlinearity in the first decade and dramatically reduces the nonlinearity in the second period this supports the notion that finnish stock returns exhibit nonlinear dependence but that the form of dependence is not chaotic

impact of speculator s expectations of returns and time scales of investment on crude oil price behaviors abstract based on time series of crude oil prices daily spot this paper analyses price fluctuation with two significant parameters speculators time scales of investment and e speculators expectations of return by using zipf analysis technique specifically by mapping returns of prices into 3 alphabeted sequences absolute frequencies and 2 alphabeted sequences relative frequencies containing the fundamental information of price fluctuations this paper empirically explores parameters and identifies various types of speculators cognition patterns of price behavior in order to quantify the degree of distortion a feasible reference is proposed an ideal speculator finally this paper discusses the similarities and differences between those cognition patterns of speculators and those of an ideal speculator the resultant analyses identify the possible distortion of price behaviors by their patterns

nonlinear dynamics and stock returns simple deterministic systems are capable of generating chaotic output that mimics the output of stochastic systems for this reason algorithms have been developed to distinguish between these two alternatives these algorithms and related statistical tests are also useful in detecting the presence of nonlinear dependence in time series in this article the authors apply these procedures to stock returns and find evidence that indicates the presence of nonlinear dependence on weekly returns from the center for research in security prices value weighted index copyright 1989 by the university of chicago

is the business cycle characterized by deterministic chaos abstract tests are conducted on u s macroeconomic data for the presence of low dimensional deterministic chaos where deterministic chaos is defined as in grandmont s 1985 walras bowley lecture or in brock 1986 the idea is to test for evidence of endogenous instability causing the business cycle low order autoregressions are hard to reject with our methods evidence of chaos is weak but our tests may be too weak to detect it evidence of nonlinearity is present in employment 1950 i to 1983 iv unemployment 1949 i to 1982 iv monthly post war industrial production and pig iron production 1877 1937

chaos significance mechanism and economic applications imagine a bargaining model say involving diplomats negotiating tariff levels or a disarmament treaty in which each party has been instructed by higher headquarters to respond to each new offer by her opposite number with a counteroffer that is to be calculated from a simple reaction function provided in advance both negotiating parties are prohibited from revealing their own reaction functions to the other if the perfectly deterministic sequence of offers and counteroffers that must emerge from these simple rules were to begin to oscillate wildly and apparently at random the negotiations could easily break down as each party not understanding the source of the problem came to suspect the other side of duplicity and sabotage yet all that may be involved as we will see is the phenomenon referred to as chaos a case that is emphatically not pathological but in which a dynamic mechanism that is very simple and deterministic yields a time path so complicated that it will pass most standard tests of randomness chaos has become a subject of great interest to specialists and nonspecialists alike besides economics it has entered the literature of geometry physics ecology and meteorology it has been written about at length in the new york times magazine and scientific american as well as technical publications this article seeks to describe what it is how it works and what it means for economics

the euro dollar exchange rate chaotic or non chaotic a continuous time model with heterogeneous beliefs abstract the aim of this paper is to develop a continuous time exchange rate model that allows for heterogeneity of the agents beliefs in order to explore non linearities and possible chaotic behaviour the theoretical model contains an intrinsic non linearity that gives rise to a jerk differential equation which is in principle capable of generating chaos the model is econometrically estimated in continuous time with euro dollar data and examined for the possible presence of chaotic motion our results indicate that the possibility of chaotic dynamics in our model is rejected

a reappraisal of the chaotic paradigm for energy commodity prices abstract energy commodity prices have been examined over the last 20 years to detect the presence of chaos as an alternative to stochastic models with contrasting results in this paper we wish to reassess the chaotic paradigm in the light of two new pieces of information with respect to the literature the appearance of noise aware estimation methods for the correlation entropy and the availability of longer time series our analysis shows that the literature has heavily underestimated the presence of noise and that chaotic characteristics coexist with stochastic ones in the time series of prices through the recurrence quantification analysis we have also observed the presence of intermittency where periods of regular behaviour are replaced by periods of chaotic behaviour which could explain the emergence of bubbles

anticipating the consequences of school reform a new use of dea we use dea type linear programming techniques to simulate a basic component of educational reform eliminating restrictions on the allocation of school personnel our technique allows us to identify potential output gains or equivalently potential cost savings from reform we can also identify which personnel groups are likely to gain and lose under this reform when we apply our model to a sample of texas school districts we find evidence that the educational establishment has substantial economic rents to protect from school reform and that the primary beneficiaries of reform are likely to be affluent school districts with few minority students the technique which relies on the relationship between the direct and indirect distance functions can be easily generalized to measure the potential gains from removing other input restrictions such as union work rules environmental regulations or deed restrictions

on nonlinear dynamics the case of the pork cycle new methods for analyzing nonlinear dynamic processes are used to evaluate the hogcorn price ratio the results present evidence of nonlinear dynamics in the pork cycle moreover while garch processes account for some of the nonlinearities the pork cycle is apparently characterized by more complex dynamic forms the empirical analysis provides some evidence of the presence of chaos in the pork cycle the results also indicate that the dynamic process generating the pork cycle is nonlinear and cannot be adequately characterized by a small number of state variables

the economics of schooling production and efficiency in public schools n recent years public and professional interest in schools has been heightened by a spate of reports many of them critical of current school policy these policy documents have added to persistent and long standing concerns about the cost effectiveness and fairness of the current school structure and have made schooling once again a serious public issue as in the past however any renewed interest in education is likely to be short lived doomed to dissipate as frustration over the inability of policy to improve school practice sets in this frustration about school policy relates directly to knowledge about the educational production process and in turn to underlying research on schools although the educational process has been extensively researched clear policy prescriptions flowing from this research have been difficult to derive 2 there exists however a consistency to the research findings that does have an immediate application to school policy schools differ dramatically in quality

is there co movement of agricultural commodities futures prices and crude oil even though significant attempts have appeared in literature the current perception of co movement of commodity prices appear inadequate and static in particular we focus on price movements between crude oil futures and a series of agricultural commodities and gold futures a comparative framework is applied to identify changes in relationships through time and various cointegration methodologies and causality tests are employed our results indicate that co movement is a dynamic concept and that some economic and policy development may change the relationship between commodities furthermore we show that biofuel policy buffers the co movement of crude oil and corn futures until the crude oil prices surpass a certain threshold

statistical inference based upon non linear science abstract this paper discusses testing for the presence of deterministic chaos and presents probems surrounding such research statistical inference methods arising from the study of non linear dynamics are presented along with research utilizing these methods the general goal of these inference methods is to test for evidence of hidden structures in economic time series data which may lead to a greater understanding of how the economy functions while evidence of significant non linear structure has been demonstrated in many economic and financial time series precisely how important these structures are to economic science is a relevant issue

the behavior of foreign exchange rates comment the distributors of foreign exchange rates are important for model building and empirical analysis for example many studies have examined foreign exchange market efficiency and currency portfolio management under the assumption that foreign exchange rates are normally distributed the statistical tests in these studies and thus their conclusions may not be reliable if the foreign exchange rates follow non normal distributions realizing the importance of the distribution of exchange rates professors calderon rossell and ben horim 1982 hereafter c b have conducted a study analyzing these distributions based on the skewness of the distribution c b have classified foreign currencies into three groups in the first group the skewness statistic was not significantly different from zero for all currencies and subperiods in the second group the distribution of changes in the foreign exchange rates was close to symmetric except for at least one subperiod in the third group the skewness statistic suggests strongly that all the distributions were asymmetric their results reveal that

is efficiency of crude oil market affected by multifractality evidence from the wti crude oil market in this paper we investigate the dynamics of relationship between efficiency and multifractality of wti crude oil market based on the cross correlation analysis and the nonlinear granger causality analysis we find that the inefficiency and multifractality of the wti crude oil returns interact positively in a nonlinear mechanism this suggests that the increase of multifractality degree will lead to the lower degree of market efficiency and vice versa our findings have some important implications for oil price forecasting and portfolio management

the behavior of foreign exchange rates reply in the preceding comment on our jibs paper 1 three basic claims are made the results in 1 are contrary to those reported elsewhere the contradiction may be due to certain weakness in the methodology employed by us based on a direct approach three currencies out of the fourteen we analyzed are regrouped two the australian dollar and japanese yen from group iii into group i currencies with a symmetric distribution and one the italian lira from group iii into group ii currencies close to have a symmetric distribution except for at least 1 subperiod andthat the arguments presented by us concerning the effects of foreign exchange management policy on exchange rates are no longer supported by the data 1986 jibs journal of international business studies 1986 17 177 180

rational choice and erratic behaviour in this paper we show that rational choice in a stationary environment can lead to erratic behaviour when preferences depend on experience we mean by erratic behaviour choice sequences that do not converge to a long run stationary value or to any periodic pattern early investigations of the effects of experience on choice goes back to pareto see also benhabib 1979 some keynesian theories of the consumption function incorporate the effects of experience and habit formation on current levels of consumption duesenberry 1949 modigliani 1949 and brown 1952 a general model of experience dependent choice was described in day 1970 and investigated in day and kennedy 1971 while the specific issue of the existence of stable representable long run consumer demand when tastes vary endogenously has been treated by gorman 1967 pollak 1970 1976 weizsaicker 1971 mccarthy 1974 and hammond 1976 pollak gave conditions for the representability of long run choice when the equations of preference dependence are linear and utility additive hammond in a generalization of these findings provides conditions for stable representable long run choice when preferences are acyclic a condition which in essence assures convergence to a long run choice

cost effectiveness measures on convex and nonconvex technologies abstract camanho and dyson 2005 extended shephard s 1974 revenue indirect cost efficiency approach to a cost effectiveness framework which helps to assess the ability of a firm to achieve the current revenue expressed in the firm s own prices and quantities at minimum cost the degree of cost effectiveness is quantified as the ratio of the minimum cost to the observed cost of the evaluated firm where the minimum cost is computed by simultaneously adjusting the output levels at the current revenue in this paper we develop two cost effectiveness approaches based on convex data envelopment analysis and nonconvex free disposable hull technologies the objectives of this paper are threefold firstly we develop a convex cost effectiveness cce measure which is equivalent to the camanho dyson cce measure under the constant returns to scale assumption secondly we introduce three nonconvex cost effectiveness ncce measures which are shown to be equivalent with respect to each returns to scale nonconvex technology finally we apply our framework to a real data

combining the assumptions of variable and constant returns to scale in the efficiency evaluation of secondary schools our paper reports on the use of data envelopment analysis dea for the assessment of performance of secondary schools in malaysia during the implementation of the policy of teaching and learning mathematics and science subjects in the english language ppsmi the novelty of our application is that it makes use of the hybrid returns to scale hrs dea model this combines the assumption of constant returns to scale with respect to quantity inputs and outputs teaching provision and students and variable returns to scale vrs with respect to quality factors attainment levels on entry and exit and socio economic status of student families we argue that the hrs model is a better informed model than the conventional vrs model in the described application because the hrs technology is larger than the vrs technology the new model provides a tangibly better discrimination on efficiency than could be obtained by the vrs model to assess the productivity change of secondary schools over the years surrounding the introduction of the ppsmi policy we adapt the malmquist productivity index and its decomposition to the case of hrs model

pairs selection and outranking an application to the s p 100 index pairs trading is a popular quantitative speculation strategy this article proposes a general and flexible framework for pairs selection the method uses multiple return forecasts based on bivariate information sets and multi criteria decision techniques our approach can be seen as a sort of forecast combination but the output of the method is a ranking it helps to detect potentially under and overvalued stocks a first application with s p 100 index stocks provides promising results in terms of excess return and directional forecasting

assessing school efficiency in portugal using fdh and bootstrapping this study explores a new data set that contains information both on inputs and outputs for a sample of portuguese secondary schools an fdh reference technology is used to determine radial technical efficiency scores and slacks although it is known that there is no reason to assume convexity in the study of education efficiency frontiers this is the first study ever to use fdh at the school level effectively relaxing the convexity assumption a two stage approach is used whereby the significant environmental variables that explain fdh efficiency scores and slacks are identified for the purpose of statistical inference the first application of the bootstrapping algorithms suggested by simar and wilson 2003 is conducted the study concludes that the unemployment rate access to health care services adult education and living infrastructures are determinants of school efficiency the differences between the coast and the interior of portugal seem to be more relevant as far as school efficiency is

are the crude oil markets becoming weakly efficient over time a test for time varying long range dependence in prices and volatility this paper analyzes the efficiency of crude oil markets brent and west texas intermediate by means of estimating the fractal structure of these time series we test for time varying degrees of long range dependence using the rescaled range hurst analysis and find evidence that this market has become more efficient over time these results are robust for controlling for short term autocorrelation by means of a shuffling procedure

testing for linear and nonlinear granger causality in the stock price volume relation linear and nonlinear granger causality tests are used to examine the dynamic relation between daily dow jones stock returns and percentage changes in new york stock exchange trading volume we find evidence of significant bidirectional nonlinear causality between returns and volume we also examine whether the nonlinear causality from volume to returns can be explained by volume serving as a proxy for information flow in the stochastic process generating stock return variance as suggested by clark s 1973 latent common factor model after controlling for volatility persistence in returns we continue to find evidence of nonlinear causality from volume to returns

are commodity prices chaotic we conduct tests for the presence of low dimensional chaotic structure in the futures prices of four important agricultural commodities though there is strong evidence of non linear dependence the evidence suggests that there is no long lasting chaotic structure the dimension estimates for the commodity futures series are generally much higher than would be for low dimension chaotic series our test results indicate that autoregressive conditional heteroskedasticity arch type processes with controls for seasonality and contract maturity effects explain much of the non linearity in the data we make a case that employing seasonally adjusted price series is important in obtaining robust results via some of the existing tests for chaotic structure finally maximum likelihood methodologies that are robust to the non linear dynamics lend strong support to the samuelson hypothesis of maturity effects in futures price changes 2002 elsevier science b v all rights reserved

forecasting crude oil market volatility further evidence using garch class models abstract this paper extends the work of kang et al 2009 we use a greater number of linear and nonlinear generalized autoregressive conditional heteroskedasticity garch class models to capture the volatility features of two crude oil markets brent and west texas intermediate wti the one five and twenty day out of sample volatility forecasts of the garch class models are evaluated using the superior predictive ability test and with more loss functions unlike kang et al 2009 we find that no model can outperform all of the other models for either the brent or the wti market across different loss functions however in general the nonlinear garch class models which are capable of capturing long memory and or asymmetric volatility exhibit greater forecasting accuracy than the linear ones especially in volatility forecasting over longer time horizons such as five or twenty days

exchange rate dynamics central bank interventions and chaos control methods abstract we use a simple chartist fundamentalist model developed by day and huang to explore recent chaos control algorithms as potential candidates for central bank intervention rules we find that methods such as delayed feedback control ogy and constant feedback have in principle the potential to reduce exchange rate variability and deviations from fundamentals even in the presence of large dynamic noise

chaotic dynamics in a cash in advance economy abstract this paper introduces sufficient conditions for the existence of deterministic cycles and chaos in cash in advance models building on the earlier work of woodford 1994 chaotic equilibria are shown to be particularly likely in the cash in advance model because of a unique characteristic of such models a discontinuous derivative in the difference equation map at the satiation level of real balances the existence of a kink means that chaotic equilibria may exist without implausibly large curvatures in the utility function since a chaotic time series that makes use of the kink would sometimes exhibit zero nominal interest rates the paper also gives an example of chaos in which nominal interest rates remain strictly positive

estimating output gains by means of luenberger efficiency measures abstract in this paper we propose a new measure of input allocative efficiency that we estimate using directional distance functions our new measure compares the gain in output if a firm reduces technical inefficiency for the direct production possibility set and the gain in output if the firm reduces technical inefficiency for the indirect production possibility set because the directional distance function uses a translated origin the gain in output from an optimal reallocation of inputs can be estimated for non radial expansions in output we estimate efficiency for japanese banks during 1992 1999 the gains in outputs from reducing allocative inefficiency by reallocating inputs are greater than the gains in outputs that can be attained by reducing technical inefficiency

stabilization policy can lead to chaos stabilization policy can lead to chaos nonlinearities in economies as elsewhere can generate chaotic equilibria the presence of pareto inferior chaotic equilibria might seem reason enough to use stabilization policy to select preferable equilibria however i show that a stabilization policy with feedback can itself lead to chaotic dynamics thus the existence of nonlinearities in the economy does not by itself justify monetary or fiscal policies aimed at reducing economic instability current evidence cannot distinguish whether monetary policy stabilizes a nonlinear economy creates nonlinear dynamics in the economy or both i introduction in recent years the claim has been made that nonlinearities and self fulfilling expectations in the private economy generate economic instability that can and should be offset by government policies this instability shows up as a positive variance in the steady state of an economy that otherwise would have a steady state with zero variance and higher utility for households on the basis of such models grandmont and malgrange 1986 9 conclude that we should expect a free market economy to perform rather badly under laissez faire in addition there is a possible role for deterministic stabilization policies that would if understood and believed eliminate forecasting mistakes and the corresponding efficiency losses and would guarantee the ultimate disappearance of endogenous fluctuations the purpose of this note is to provide a simple example of stabilization policy leading to chaotic time series behavior this example is an elaboration of friedman s 1953 classic argument that with uncertain knowledge about the economy stabilization policy can increase the variance of the goal variable nonlinearities can make as much a case against stabilization policy as for it the example is ad hoc in some respects but it is based on common ingredients of many models ii a simple example interesting aspects of an economy can be summarized by the quantity equation 1 mv y assume that real income y is constant which implies that changes in nominal income are proportional to changes in the price level in one respect using the quantity equation means that the example below does not have the same force as a tight general equilibrium model of the economy without the underlying detail equation 1 is ad hoc in another respect the example below has more force an equation such as 1 commonly characterizes the general equilibrium models in which money has a significant effect on the economy hence one interpretation is that the example has some generality assume that the monetary authority targets nominal income and knows 1 that the quantity theory characterizes the long run equilibrium of the economy and 2 the level of velocity that is consistent with zero inflation v in these circumstances there is one obvious equilibrium consistent with the goal the money stock is constant and the public expects a constant money supply and zero inflation in this equilibrium nominal income can be stabilized at the target level of nominal income y the monetary authority just need set the money supply to m v 1y if the monetary authority is uncertain about the public s response to its actions one strategy is to adopt a cautious stabilization policy to support the economy s approach to the long run deterministic equilibrium one commonly proposed set of feedback rules is the proportional policies introduced by phillips 1954 in the levels such a rule for the money supply is 2 m m alpha y y sub 1 where y sub 1 is last period s nominal income and alpha is the adjustment parameter assume that private agents believe that the monetary authority eventually will accomplish its goal of setting y equal to y

are the crude oil markets really becoming more efficient over time some new evidence abstract we replicate the study of tabak cajueiro 2007 are the crude oil markets becoming weakly efficient over time a test for time varying long range dependence in prices and volatility published in energy economics 29 pp 28 36 the results have been mostly confirmed specifically we have confirmed that the crude oil markets efficiency could be rejected up till approximately 1994 and this holds for both studied crude oil commodities brent and wti analyzing an extended dataset up till june 2017 we find that the markets remained efficient at least with respect to long range dependence until the outbreak of the global financial crisis in 2008 this is confirmed by all three applied methods the rescaled range analysis used in the original study and the detrended fluctuation analysis and the geweke porter hudak estimator which were added to strengthen validity of the results the markets returned back to efficiency around 2012 and remained there until 2015 when the hurst exponent started another rally and stayed rather high until the end of the examined sample comparing the two markets the brent crude oil shows stronger signs of inefficiency during the inefficient periods compared to the wti crude oil this is in hand with the results reported in the original study apart from rerunning the analysis on an extended dataset and using two additional methods we also provide a firmer validity check using the moving block bootstrap procedure which outperforms the original shuffling procedure in the provided forecasting study

cointegration and detectable linear and nonlinear causality analysis using the london metal exchange lead contract this study applies linear and nonlinear granger causality tests to examine the dynamic relation between london metal exchange lme cash prices and three possible predictors the analysis uses matched quarterly inventory uk treasury bill interest rates futures prices and cash prices for the commodity lead traded on the lme the effects of cointegration on both linear and nonlinear granger causality tests is also examined when cointegration is not modelled evidence is found of both linear and nonlinear causality between cash prices and analysed predictor variables however after controlling for cointegration evidence of significant nonlinear causality is no longer found these results contribute to the empirical literature on commodity price forecasting by highlighting the relationship between cointegration and detectable linear and nonlinear causality the importance of interest rate and inventory as well as futures price in forecasting cash prices is also illustrated failure to detect significant

public sector performance move or monitor governmental performance is a concern of citizens and politicians alike a specific interest is public sector waste which is thought to be pervasive and efforts to improve public sector performance are believed to be minimal economists have studied the topic extensively this paper discusses options on measuring public sector performance in urban areas and it also suggests certain public policy options that i believe deserve additional attention from a citizen s point of view when public service performance declines one can leave the jurisdiction this exit option has a substantial historical precedent in the united states going back to at least the landing of the mayflower in the urban public finance literature this is a consequence of the tiebout 1956 model in which there are a sufficient number of jurisdictions among which individuals may choose to live and people vote with their feet the model suggests that exit or the threat of exit leads to competitive forces that improve efficiency in the public sector an alternative to exit comes about through monitoring and voting monitoring and voting are attractive ways to effect change for individuals who do not want to exit as suggested by davis and hayes 1993 a fairly simple model can demonstrate the demand for good government there is a literature that examines the motives for exit dowding and john 1996 which points out and concludes that people may not move in response to the fiscal decisions of local governments perhaps voting and monitoring are more attractive options at least to a proportion of the population 2 this paper explores the move monitor trade off in influencing urban public sector performance although heuristic arguments can be made concerning the relative importance of moving or monitoring few researchers have investigated when if ever move and or monitor are effective means of improving public sector efficiency in this paper i would like to suggest that there are gaps in the literature proposing topics or future research

non linear granger causality in the currency futures returns abstract this paper examines the relationship between currency futures returns by employing a test for non linear causality the results indicate evidence of unidirectional non linear causality relationship in four cases however after filtering the returns using a garch 1 1 model we find insignificant and statistically weaker non linear causality relationships

is the us business cycle asymmetric some further evidence evidence of nonlinearity in growth rates of monthly industrial production unit labour costs consumer prices and unemployment is reported and alternative representations of that nonlinearity exami

trading asymmetric trend and volatility by leverage trend garch in taiwan stock index this article develops a leverage trend generalized autoregressive conditional heteroscedasticity garch model by incorporating asymmetric trend of returns of the exponential autoregressive and asymmetric volatility of garch models to study the asymmetric effects using in sample daily data of taiex over the period 4 january 1980 to 25 august 1997 and postsample daily data over the period 26 august 1997 to 10 september 2007 the evidence reveals that a curvaceous risk return relationship and both asymmetric volatility and asymmetric trend of returns are significant in taiex the episode of asymmetric trend of returns is that the positive information creates a higher return trend than the negative information of the same amount while similarly to most studies the evidence of asymmetric volatility appears that the negative information makes a higher volatility than the positive information of the same size most remarkably we evidence that the volatility asymmetry effect is a conservative trading factor

the role of the reference technology in measuring productive efficiency after a twenty year lull the measurement of productive efficiency is enjoying a revival in particular the index of efficiency developed by debreu i95i and later utilised by farrell i957 has received considerable attention these measures have been used fairly extensively in empirical work in both the operations research and economic literature these types of indexes have also appeared in the growing literature on testing for regularity conditions in production e g in afriat i972 diewert and parkan i983 and varian 1984 since the farrell type measure is the focus in this paper a brief review is useful in the farrell framework overall efficiency oe can be decomposed into two multiplicative components allocative efficiency ae and technical efficiency te

threshold arch models and asymmetries in volatility this paper attempts to enlarge the class of threshold heteroscedastic models tarch introduced by zakoian 1991a we show that it is possible to relax the positivity constraints on the parameters of the conditional variance unconstrained models provide a greater generality of the paths allowing for nonlinearities in the volatility cyclical behaviour is permitted as well as different relative impacts of positive and negative shocks on volatility depending on their size we give empirical evidence using french stock returns

forecasting energy market volatility using garch models can multivariate models beat univariate models abstract in this paper we forecast energy market volatility using both univariate and multivariate garch class models first we forecast volatilities of individual assets and find that multivariate models display better performance than univariate models second we forecast crack spread volatility and contrast the performance of multivariate models for two underlyings with the alternative of univariate ones for crack spreads directly our evidence shows that univariate models allowing for asymmetric effects display the greatest accuracy we also discuss the hedging strategy based on multivariate models and its implications for market participants

some evidence concerning macroeconomic chaos abstract an empirical assessment of a linear stochastic perspective for canadian macroeconomic time series is presented the methods used are based on the mathematics of chaos present evidence suggests that low order deterministic chaos does not provide a satisfactory characterization of the data the absence of significant nonlinear structure for the investment and unemployment series is of particular note in light of past findings with american data the degree to which the use of a time trend can impose a pseudo structure on the data is illustrated

the production characteristics of local public education a multiple product and input analysis since the seminal work of baumol panzer and willig 1 economists have become increasingly interested in incorporating the multifaceted nature of real world production functions into their empirical analyses multiproducts multiple inputs and the relaxation of the long run equilibrium condition are some prime examples of major innovations in production modeling an excellent example of this innovative literature is the study by cowing and holtmann 7 that focuses on the short run production characteristics associated with the hospital services industry specifically cowing and holtmann find evidence contrary to long run equilibrium and that economies of scope are at least as important as economies of scale in the production of hospital services moreover several empirical studies relating to the production characteristics of other goods and services such as higher education 6 crime prevention 9 electric utilities 15 and airlines 5 have provided ample evidence that these pertinent factors matter from both an econometric and a policy perspective the literature concerning the production characteristics of primary and secondary education however has lagged behind in terms of incorporating more realism into the analysis typically studies concerned with primary and secondary education production 2 3 13 14 maintain that schools operate at a long run equilibrium position and produce a single output with a single input i e teachers thus assuming away factors which these other industry studies have found to be significant in fact jimenez 12 is the only study to date on local primary and secondary education production that is based on less restrictive assumptions several limitations are associated with his research however each of these limitations reduce the generality of his findings concerning the production characteristics of primary and secondary education first jimenez employs a small sample to obtain estimates of various production characteristics bringing into question the overall

assessing the technical and allocative efficiency of hospital operations in greece and its resource allocation implications abstract in this paper we seek to develop a research framework concerning the assessment of the efficiency of public sector hospital operations public hospitals are increasingly under pressure to improve their operations both in terms of resources they use and also in terms of the quantity and quality of their outcomes the assessment of efficiency entails both the notions of technical and allocative efficiency as they yield complementary information about the management effectiveness of individual hospitals technical efficiency has a diagnostic purpose as it yields comparative information about the effectiveness with which individual units convert their input resources into outputs on the other hand allocative efficiency has a planning orientation since the objective of the assessment is to gauge efficiency improvements by means of resource reallocation a linear programming based model is proposed for assessing allocative efficiency in the light of uncertainty about the prices of input factors the empirical part of the paper is based on data from greek public hospitals results and policy implications are discussed based on data from 98 general hospitals based on information from 1992 it was found that significant inefficiencies are present in the operations of greek hospitals that account approximately for 100 mecu in 1992 prices

estimating output allocative efficiency and productivity change application to japanese banks abstract a new measure of output allocative efficiency is developed by comparing the input technical efficiency of a firm for the direct input requirement set and the indirect input requirement set proposed by shephard indirect production functions verlag anton hain meisenheim am glan the ratio of the direct and indirect input quasi distance functions serves as the measure of output allocative efficiency as such it measures the ratio of potential to actual inputs if the firm had chosen the revenue maximizing output mix using panel data on japanese banks operating during 1992 1996 productivity growth is measured and decomposed into changes in output allocative efficiency changes in input technical efficiency and technical change during the period japanese banks experienced productivity declines averaging 2 per year and could have used only 78 93 of actual inputs if they had chosen the revenue maximizing output mix

an indirect approach to the evaluation of producer performance in this paper we suggest a somewhat new analytical approach to producer performance evaluation the suggested approach is somewhat new in that it synthesizes existing analytical techniques from three areas and uses them to look at performance evaluation in a new way the approach is particularly relevant to public sector or service sector contexts in which the performance of alternative providers of a public service is to be evaluated in these contexts any of the following conditions may hold 1 the standard profit maximizing cost minimizing or revenue maximizing paradigms are inappropriate 2 prices of some services being provided or of some resources being consumed are either nonexistent or unobserved 3 observed prices are not exogenous due to monopoly or monopsony power examples abound it is frequently argued that the provision of medical legal educational transportation employment and many other services by public or private agencies is driven by goals other than the maximization of profit moreover these and many other services such as police and fire protection do not always have market prices with which to value them in addition the lack of competition in the provision of many such services and thus in the employment of specialized resources used in their provision makes it dangerous to use existing but distorted market prices to compare the performance of providers on the basis of revenue or cost much less profit

some empirical evidence on the time series properties of four uk asset prices in this paper the authors examine the time series behavior of four u k asset prices and estimate two types of models for the differenced series much previous research has found the presence of time varying heteroskedasticity in the error process for asset prices a linear model with gqarch errors is compared to a joint bilinear model with gqarch errors the latter choice motivated by the ability of bilinear models to capture turbulent behavior the adequacy of these models is determined by examining simulations and also employing test statistics the forecasting performance of the two models is also compared copyright 1996 by the london school of economics and political science