an empirical examination of the implications of arbitrage pricing theory abstract this paper presents a comprehensive set of tests of the implications of the arbitrage pricing theory we find unlike previously reported results a very limited relationship between the expected returns and the covariance factor loadings measures of risk furthermore unique variance measures of risk while generally making only small contributions to the explanation of asset returns turn out to be significant about as frequently as the coveriance measures of risk which is inconsistent with the arbitrage pricing theory model the intercept tests are more mixed but provide only limited support to the model

network models and financial stability abstract systemic risk is a key concern for central banks charged with safeguarding overall financial stability in this paper we investigate how systemic risk is affected by the structure of the financial system we construct banking systems that are composed of a number of banks that are connected by interbank linkages we then vary the key parameters that define the structure of the financial system including its level of capitalisation the degree to which banks are connected the size of interbank exposures and the degree of concentration of the system and analyse the influence of these parameters on the likelihood of knock on defaults first we find that the better capitalised banks are the more resilient is the banking system against contagious defaults and this effect is non linear second the effect of the degree of connectivity is non monotonic i e initially a small increase in connectivity increases the contagion effect but after a certain threshold value connectivity improves the ability of a banking system to absorb shocks third the size of interbank liabilities tends to increase the risk of knock on default even if banks hold capital against such exposures fourth more concentrated banking systems are shown to be prone to larger systemic risk all else equal in an extension to the main analysis we study how liquidity effects interact with banking structure to produce a greater chance of systemic breakdown we finally consider how the risk of contagion might depend on the degree of asymmetry tiering inherent in the structure of the banking system a number of our results have important implications for public policy which this paper also draws out

measuring the pricing error of the arbitrage pricing theory this article provides an exact bayesian frame work for analyzing the arbitrage pricing the ory apt based on the gibbs sampler we show how to obtain the exact posterior distributions for functions of interest in the factor model in particular we propose a measure of the apt pricing deviations and obtain its exact posterior distribution using monthly portfolio returns grouped by industry and market capitalization we find that there is little improvement in reduc ing the pricing errors by including more factors beyond the first one as an important extension of the asset pricing model of sharpe 1964 and lintner 196 5 ross 1976 1977 derived the arbitrage pricing theory apt which addresses a fundamental problem in finance to char acterize the expected return on a security the apt implies that the expected return is approximately a

approximate factor structures interpretations and implications for empirical tests this paper provides some new insights about approximate factor structures as defined by chamberlain and rothschild 2 and their implications for empirical tests first we show that any economy that satisfies an approximate factor structure can be transformed in a manner that does not alter the characteristics of investor portfolios into an economy that satisfies an exact factor structure as defined by ross 9 second we show that principal components analysis represents just one of many methods of forming groups of well diversified portfolios with no idiosyncratic risk in large samples correct factor loadings will be obtained by regressing security returns on any group of these portfolios our interpretations of the chamberlain and rothschild results also provide additional insights into the testability of the arbitrage pricing theory we show that securities cannot be repackaged to hide factors in the manner suggested by shanken 10 without the variance of some of the repackaged securities approaching infinity in large economies

sequential tests of the arbitrage pricing theory a comparison of principal components and maximum likelihood factors we examine the cross sectional pricing equation of the apt using the elements of eigenvectors and the maximum likelihood factor loadings of the covariance matrix of returns as measures of risk the results indicate that for data assumed stationary over twenty years the first vector is a surprisingly good measure of risk when compared with either a one or a five factor model or a five vector model we conclude that in some circumstances principal components analysis may be preferred to factor analysis

sectoral shocks and aggregate fluctuations abstract this paper presents a multisector dynamic general equilibrium model of business cycles with a distinctive feature aggregate fluctuations are driven by independent sectoral shocks the model hypothesizes that trade among sectors provides a strong synchronization mechanism for these shocks due to the limited but locally intense interaction that is characteristic of such input trade flows limited interaction characterized by a sparse intermediate input use matrix reduces substitution possibilities among intermediate inputs which strengthens comovement in sectoral value added and leads to a postponement of the law of large numbers in the variance of aggregate value added the chief virtue of this model is that reliance on implausible aggregate shocks is not necessary to capture the qualitative features of macroeconomic fluctuations building on horvath 1998 review of economic dynamics 1 781 808 which establishes the theoretical foundation for the relevance of limited interaction in the context of a stylized multisector model this paper specifies a more general multisector model calibrated to the us 2 digit standard industrial code economy simulations prove the model is able to match empirical reality as closely as standard one sector business cycle models without relying on aggregate shocks

exact arbitrage well diversified portfolios and asset pricing in large markets abstract for a market with an atomless continuum of assets we formulate the intuitive idea of a well diversified portfolio and present a notion of exact arbitrage strictly weaker than the more conventional notion of asymptotic arbitrage and necessary and sufficient for the validity of an apt pricing formula our formula involves essential risk one based on a specific index portfolio constructed from factors and factor loadings that are endogenously extracted to satisfy an optimality property involving a finite number of factors we illustrate how our results can be translated to markets with a large but finite number of assets

a fuzzy goal programming approach to portfolio selection abstract portfolio selection is a usual multiobjective problem this paper will try to deal with the optimum portfolio for a private investor taking into account three criteria return risk and liquidity these objectives in general are not crisp from the point of view of the investor so we will deal with them in fuzzy terms the problem formulation is a goal programming g p one where the goals and the constraints are fuzzy we will apply a fuzzy g p approach to the above problem to obtain a solution then we will offer the investor help in handling the results

measuring the systemic risk in interfirm transaction networks using a unique and massive dataset that contains information on interfirm transaction relationships this study examines default propagation in trade credit networks and provides direct and systematic evidence of the existence and relevance of such default propagation not only do we implement simulations in order to detect prospective defaulters we also estimate the probabilities of actual firm bankruptcies and compare the predicted defaults and actual defaults we find first that an economically sizable number of firms are predicted to fail when their customers default on their trade debt second these prospective defaulters are indeed more likely to go bankrupt than other firms third firms that have abundant external sources of financing or whose transaction partners have such abundant sources are less likely to go bankrupt even when they are predicted to default this provides evidence for the existence and relevance of firms called deep pockets by kiyotaki and moore 1997 that can act as shock absorbers

a study of cartel stability the joint executive committee 1880 1886 this article employs weekly time series data on the joint executive committee railroad cartel from 1880 to 1886 to test empirically the proposition that observed prices reflected switches from collusive to noncooperative behavior an equilibrium model of dynamic oligopoly with asymmetric firms together with explicit functional form assumptions about costs and demand determines the estimating equations and stochastic structure of the econometric model the hypothesis that no switch took place so that price and quantity movements were solely attributable to exogenous shifts in the demand and cost functions is then tested against this alternative and rejected

interpreting the factor risk premia in the arbitrage pricing theory abstract in the arbitrage pricing theory of ross assets expected returns are shown to be approximately linear in the factor loadings of the process generating returns this note provides a very simple and direct proof of the proposition that the coefficients in this approximate pricing relation can be interpreted as the excess returns on portfolios perfectly correlated with the factors whenever a riskless asset and such mimicking portfolios exist

treasury bill factors and common stock returns capital asset pricing theory gives a linear ex ante relationship between a security s return and one special portfolio return the return on all assets this linear equation is called the capital asset pricing model capital asset pricing theory alone provides no empirical hypotheses because it is derived and defined wholly with expectations tests of empirical hypotheses with historical data require an additional proposition that relates ex ante and ex post returns a model for this second proposition is called a return generating equation arbitrage pricing theory gives a more compact method for deriving a linear ex ante security return model in the arbitrage theory developed by ross 6 the return generating equation is the basis for the ex ante return relationship briefly an approximate linear expected return equation is derived directly from the return generating equation so two separate models are not required in addition the ex ante return equation is defined in terms of an arbitrary number of special factor portfolio returns rather than a single market portfolio return in this sense arbitrage pricing theory has richer implications and a simpler structure than capital asset pricing arbitrage pricing theory starts with a linear return generating equation for each security

on the diversification observability and measurement of estimation risk this paper reexamines how risk return relationships are affected by investor uncertainty about the exact parameters of the joint rate of return distribution we attempt to clarify results relating to three central issues first we address the issue of diversification focusing on an apt factor model framework second we discuss the observability of estimation risk and describe research experimental designs that should encompass the existence of estimation risk and reveal it in the data finally we suggest exploiting contemporaneous return observations on high and low information securities to aid in the measurement of return parameters for low information securities

some results in the theory of arbitrage pricing this paper derives a stronger version of huberman s recent preference free pricing theorem this pricing result relates the expected return on an asset to its factor responses and the covariance structure of the residuals from a linear factor model it must characterize any infinite asset economy in which no arbitrage opportunities are present whether or not the factor model has uncorrelated residuals this result provides the intuition for the role of residual risk in the pricing model and eliminates some classes of arbitrage opportunities still present under huberman s bound some applications to empirical tests and performance measurement are also discussed the arbitrage pricing theory is one of several financial pricing models which attempts to explain the cross sectional variation in expected returns on assets in certain respects it is similar to the capital asset pricing model but there are both substantive and subtle differences one of the key advantages of the apt is that it derives a simple linear pricing relation approximating that in the capm without some of the latter s objectionable assumptions perhaps the key disadvantage of the apt is that it provides no clues as to what might be important factors nor as to how to interpret the factor premiums which appear in the pricing equation this paper serves several purposes after reviewing the linear factor model formulation in section i it derives in section ii a stronger version of huberman s 9 recent preference free pricing theorem this pricing result relates the expected return on an asset to its factor responses and the covariance structure of the residuals this relation must characterize any infinite asset economy in which no arbitrage opportunities are present whether or not a linear factor model with uncorrelated residuals is the appropriate returns generating mechanism section iii specializes this result by eliminating the effects of residual covariances and compares the results here to those of previous apt models when applied to the standard linear factor model with uncorrelated residuals this new pricing bound eliminates arbitrage opportunities which remain under huberman s bound this result also provides for the first time the intuition for the role of residual risk in the approximate pricing relation section v provides an interpretation of the factor premiums and gives a valid asset pricing model interpretation to the apt which is consistent with merton s

exact arbitrage pricing and the minimum variance frontier the author examines the relationship between the arbitrage pricing theory of ross and mean variance analysis in particular conditions are derived on the vector of the factor risk premia that are equivalent to the existence of a strictly positively weighted portfolio on the minimum variance frontier also a sufficient condition is given under which the existence of a positive minimum variance portfolio of all the assets in the economy will imply the existence of a positive minimum variance portfolio on a subset this means that rejection of the hypothesis of the existence of a positive minimum variance portfolio on a subset satisfying this condition implies rejection for the whole set a growing body of literature explores the relationship between the arbitrage pricing theory apt of ross 13 14 and the mean variance model among the early work in this direction were the papers of chamberlain and rothschild 2 and chamberlain 1 these papers examine a sequence of economies and characterize the relationship in the limit between the mean and portfolio cost functionals and the minimum variance frontier chamberlain 1 also gives a condition under which exact arbitrage pricing will hold dybvig 4 and grinblatt and titman 7 examine equilibrium models in an apt context for a finite economy they derive sharp bounds on the deviation from exact arbitrage pricing recent papers by huberman kandel and stambaugh 9 and grinblatt and titman 8 explore the relationship between the apt and the mean variance model by studying portfolios that can be used as proxies for the factors and examining the relationship these portfolios bear to the minimum variance frontier these two papers also deal with equilibrium models in spite of the number and variety of equilibrium apt models the question of the pricing of factor risk in equilibrium remains largely unexplored this paper makes some progress in addressing that issue by looking at a given equilibrium restriction and studying the constraints it imposes on the vector of factor premia itself the most familiar equilibrium restriction we might study is the central implication of the capital asset pricing model capm that the market portfolio is efficient in particular no portfolio with the same expected return as the market portfolio has a smaller variance the restriction we actually study is weaker than

an international arbitrage pricing model with ppp deviations an internation al arbitrage pricing model with ppp deviations i introduction there is a growing literature examining the implications of purchasing power parity ppp deviations in international asset pricing models this literature typically assumes that residents of a country deflate nominal returns by their national price index in order to determine real returns in this setting stochastic ppp deviations imply that the real return on an asset differs internationally this international difference in real returns has forced authors to make important simplifying assumptions in order to derive international asset pricing models solnik 1974 develops an international capital asset pricing model icapm assuming no inflation and no correlation between ppp deviations and local real returns his model is extended by sercu 1980 to permit correlation between exchange rates and local real returns and by kouri and de macedo 1978 to allow for nonstochastic inflation this paper abandons the icapm approach in order to price assets in a setting of stochastic inflation rates stochastic ppp deviations and correlation between ppp deviations and real asset returns without imposing concomitant restrictions on agents utility functions 1 the paper extends ross s 1976 arbitrage pricing theory to an international environment with ppp deviations it improves upon solnik s 1983 and ross and walsh s 1983 international arbitrage pricing models iapm by i allowing both stochastic inflation and stochastic ppp deviations ii demonstrating how returns may be translated into any nominal or real numeraire and iii emphasizing the dynamic nature of international asset pricing in addition the model specifies risk the price of risk and the translation of these variables between all nominal and real numeraires as functions of the model s fundamental state variables this yields testable restrictions not found in domestic arbitrage pricing models apm 2 after deriving an iapm with ppp deviations this paper uses the model to examine the forward exchange market s riks premium the model s state variables determine the stochastic structure of ppp deviations and national price levels which in turn define the dynamics of risk and the price of risk the analysis demonstrates the potentially central role of ppp deviations in determining the evolution of forward exchange risk premia since the source of the bias between forward and future spot exchange rates has not bee convincingly identified and since ppp deviations have not been highlighted in studies of this bias future empirical investigations concerning the systematic discrepancies between forward and future spot exchange rates should incorporate ppp deviations 3 the model s equations are discussed in section ii section iii derives an intertemporal iapm with ppp deviations demonstrates how to translate risk and the price of risk into any nominal or real numeraire using the model s state variables and identifies testable restrictions not found in the domestic apm section iv derives and examines the forward exchange market s risk premium and section v presents a brief summary ii the model the world economy consists of n 1 countries each with its own currency currency 0 is arbitrarily chosen as the nominal numeraire every investor is able to issue and purchase assets in any country through freely floating international exchange markets it is assumed that country i has n sub i assets and the total number of assets mathematical expression omitted is much larger than the number of countries n 1 for convenience the first n 1 assets are nominally riskless in local currency terms so that asset o is country o s nominally riskless asset although all goods are available in each country residents of country i can consume only goods purchased in country i

stable factors in security returns identification using cross validation recent papers in financial research focus on identifying a stable factor structure for security returns the likelihood ratio test typically is used to determine the number of factors from exploratory factor analysis models in this article we consider the use of cross validation to identify a stable factor structure in security returns when applied to actual stock return data cross validation identifies a smaller number of stable factors than the likelihood ratio test in groups of 30 60 randomly selected securities cross validation suggests one dominant factor whereas the likelihood ratio test identifies from four to six factors furthermore when groups are designed to highlight industry or size effects the discovery of more than one dominant factor is problematic even if there are multiple economic factors generating stock returns they may be difficult to disentangle if the underlying factors tend to be correlated

the relation between mean variance efficiency and arbitrage pricing the mean standard deviation diagram has proven to be a valuable tool for understanding equilibrium asset pricing theory first introduced by markowitz 1952 1959 and tobin 1958 the diagram helps students and researchers alike to develop intuition about the capital asset pricing model capm its properties are useful for analyzing the conditions under which the market portfolio is mean variance efficient and for linking the location of the market portfolio in the diagram with the validity of the capm in addition its simple geometry seems to be the critical inspiration for roll s 1977 argument that the capm cannot feasibly be tested because the market portfolio is unobservable and because of a mathematical equivalence between the individual return beta linearity relation and the market portfolio s mean variance efficiency p 129 recent research on equilibrium asset pricing both theoretical and empirical has tended to focus on multibeta pricing models especially the arbitrage pricing theory apt this paper will show that the simple intuition derived from the

arbitrage and diversification in a general equilibrium asset economy this paper presents a theory of equilibrium asset pricing that generalizes the recent work of connor the model extends connor s results to more general sets of asset returns and consumer preferences introduces production and provides a framework for analyzing exact and approximate equilibrium asset pricing the other major contribution of the paper is the introduction of geometric arguments that exploit the properties of induced prefer ences over assets this method of analyzing asset pricing provides an intuitively appealing way of analyzing equilibrium asset pricing theories unifies several well known asset pricing models this paper extends connor s finite asset model in a number of directions these extensions are nontrivial because they allow the theory to encompass asset pricing models that were excluded by connor s assumptions the second major contribution of the paper is to introduce a method of argument that exploits the geometric properties of induced preferences over assets and characterizes asset prices using these proper ties this technique provides an intuitively appealing way of analyzing asset pricing theories for a simple geometric exposition of the main ideas in this paper see milne 1987 0 2 to place this paper in the context of the literature it is important to appreciate the development of asset pricing models over the last two decades the first and perhaps the most famous asset pricing model is the capital asset pricing model capm developed by sharpe 1964 and lintner 1965 the model demonstrated a striking result assuming i consumers characterize portfolios in terms of the means and variance of rates of return ii there exists a risk free asset and iii asset market equilibrium then any asset s expected rate of return could be written as a linear function of the riskless interest rate and the expected rate of return on the endowment of risky assets the so called market portfolio the original capm result was derived from a one period model but merton 1973 showed that in a continuous time model where returns could be char acterized by a diffusion process the same mean variance argument could be applied to obtain the capm formula it was well known that if consumers had von neumann morgenstern prefer ences then either quadratic utility and or multivariate normality of returns were

arbitrage asset pricing under exchange risk this paper extends the arbitrage pricing theory to an international setting specifying a linear factor return generating model in local currency terms the author shows that the usual risk diversification rule in the arbitrage pricing theory does not yield a riskless portfolio unless currency fluctuations obey the same factor model as asset returns the author then considers an arbitrage portfolio whose exchange risk is hedged by foreign riskless bonds under the resulting no arbitrage conditions the expected returns are not on the same hyperplane unlike the closed economy arbitrage pricing theory unless they are adjusted by the cost of exchange risk hedging copyright 1991 by american finance association

small sample tests of portfolio efficiency abstract this paper presents an eigenvalue test of the efficiency of a portfolio when there is no riskless asset complementing the test of gibbons ross and shanken 1989 besides optimal upper and lower bounds an easily implented numerical method is provided for computing the exact p value our approach makes it possible to draw statistical inferences on the efficiency of a given portfolio both in the context of the zero beta capm and with respect to other linear pricing models as an application using monthly data for every consecutive five year period from 1926 to 1986 we reject the efficiency of the crsp value weighted index for most periods

optimal cartel trigger price strategies abstract a dynamical model of industry equilibrium is described in which a cartel deters deviations from collusive output levels by threatening to produce at cournot quantities for a period of fixed duration whenever the market price falls below some trigger price in this model firms can observe only their own production level and a common market price the market demand curve is assumed to have a stochastic component so that an unexpectedly low price may signal either deviations from collusive output levels or a downward demand shock

complementarities and comovements short run interindustry comovement may be due either to common shocks or to complementarities that progagate shocks across sectors this paper assesses the importance of input output linkages aggregate activity spillovers and local activity spillovers to comovement in postwar u s manufacturing i find that input output linkages and local activity spillovers are important to comovement while aggregate activity spillovers are not important i find that complementarities are important to aggregate volatility even after i remove observable aggregate shocks from the data local spillovers are particularly important explaining between 15 and 36 percent of manufacturing employment volatility the importance of local spillovers stems from the fact that industries that cluster together in space also comove through time contrary to the marshallian idea that industries with negatively correlated fluctuations should cluster together in order to stabilize local demand

on testing the arbitrage pricing theory inter battery factor analysis this paper tests the arbitrage pricing theory apt by estimating the factor loadings that are consistent between two industry groups of securities one of the pitfalls in the study by roll and ross is that the factors estimated in one group may not be the same with the factors estimated in another group this raises some concerns on the acceptability of their conclusions for our study we employ inter battery factor analysis which enables us to estimate factor loadings by constraining the factors to be the same between two different groups our results show that there seem to be five or six inter group common factors that generate daily returns for two industry groups of securities and these inter group common factors do not seem to depend on the size of groups also based on our cross sectional tests on the risk premia we conclude that the apt should not be rejected the arbitrage pricing theory apt introduced by ross 35 36 provides another model for explaining the relationship between return and risk the apt may be conceived as an alternative to the well known capital asset pricing model capm introduced by sharpe 39 lintner 27 and mossin 29 and later modified by black 1 both models assert that every asset must be compensated only according to its systematic risk one of the major differences is that in the capm the systematic risk of an asset is defined to be the covariability of the asset with the market portfolio whereas in the apt the systematic risks are defined to be the covariability with not only one factor but also possibly with several economic factors another difference is that the capm requires the economy to be in equilibrium whereas the apt requires only that the economy has no arbitrage opportunities note that the absence of arbitrage condition is necessary but not sufficient for the economy to be in equilibrium thus the apt is a more fundamental relationship than the capm in the sense that a rejection of the apt implies the rejection of the capm but not vice versa despite numerous attempts the capm has not been satisfactorily tested and furthermore roll s critique 32 33 casts serious doubts on the testability of the capm itself roll argues that the linear relationship between return and risk will hold for any efficient portfolio thus unless the market portfolio is observed a test of the capm using ex post data is ambiguous it results only in testing the

an asset pricing theory unifying the capm and apt this study shows that the competitive equilibrium version of the arbitrage pricing theory may be extended to develop an exact mode l if idiosyncratic risks obey the ross separating distribution the r esults indicate that one only need add the market portfolio as an ext ra factor to the factor model in order to obtain an exact asset prici ng relation the empirical arbitrage pricing theory is also general ized to allow for some factors to be omitted from the econometric m odel employed to test the theory the importance of the market portfo lio is shown to be a monotonic increasing function of the number of o mitted factors copyright 1988 by american finance association

hypothesis testing with the sharpe and treynor portfolio abstract using the scholes and williams 1977 model consistent estimates of the variances and covariances of security returns under conditions of non synchronous trading are derived the effects of using such corrected estimates on the measurement of portfolio performance are illustrated by assessing the performance of a value and equally weighted portfolio of all the stocks issued under the quebec stock savings plan qssp

integration or segmentation of the canadian stock market evidence based on the apt the domestic and international arbitrage pricing theories are modified to encom pass the hypotheses that the canadian and global north american equity markets are com pletely or partly integrated segmented the exchange rate determination literature is used to identify potentially priced binational factors and the sensitivities and factor prices are es timated using non linear sur the two equity markets are only partly integrated segmented canadian stock returns are influenced by the pure domestic components of the term structure and lagged industrial production and by the pure international components of the differential

optimal managerial contracts and equilibrium security prices recent developments in economic theory have focused attention on efficient methods for providing incentives within a corporation especially to top management jensen meckling 12 have examined some implications of incentive or agency problems for corporate finance in this paper we combine a simple model of security market equilibrium with that of an optimal managerial incentive contract using results of harris raviv 8 and holmstrom 9 we provide a rationale for including security prices in the managerial incentive contracts of publicly held firms in this model we also show that non systematic diversifiable risks will be considered in the capital budgeting decisions of a managerial firm operated in the interests of its stockholders this is in contrast to the implication of the arbitrage pricing theory a similar result follows from the capital asset pricing model which abstracts from incentive problems and suggests that only systematic risks ought to be considered the optimal contract model of the corporation takes the following view of the firm since decision makers within a firm are not sole owners of the business but employed agents the decisions which they make depend on the incentives which the organization provides these incentives are embodied explicitly in employment contracts and implicitly through the threat of dismissal or effect on reputation the contract whether explicit or not describes the decision maker s anticipation of the consequences to him conditional on various observable outcomes these outcomes are used to provide information useful in determining whether he did his job properly in the simplest optimal contract scenario there is a single principal and a single agent whose decision concerns the level of effort he expends the level of effort affects the level of output of the firm but not unambiguously because the output is also governed by other stochastic elements as a result some information about the agent s level of effort can be inferred

efficient funds for meager asset spaces abstract for finite state space models of securities markets there exists a portfolio of traded securities on which conventional call or put options suffice to complete securities markets 28 moreover these efficient funds are generic 2 18 the objective of this paper is to present a class of larger models of securities markets for which existence and genericity of efficient funds obtains conditions abstracted from the finite state space case serve to define a meager asset space it is shown that for meager asset spaces satisfying a separability condition efficient funds exist and are generic in a category theoretic sense

trade credit and the propagation of corporate failure an empirical analysis using an exhaustive data set on claims held by trade creditors suppliers on failed trade debtors customers we quantify the importance of trade credit chains for the propagation of corporate bankruptcy we show that trade creditors experience significant trade credit losses due to trade debtor failures and that creditors bankruptcy risks increase in the size of incurred losses by exploring the roles of financial constraints and creditor debtor dependences we infer that the trade credit failure propagation mechanism is driven by both credit losses and demand shrinkage finally we show that the documented propagation mechanism constitutes a significant part of the overall bankruptcy frequency suggesting that it has measurable implications for the aggregate level

a new approach to testing asset pricing models the bilinear paradigm we propose a new approach to estimating and testing asset pricing models in the context of a bilinear paradigm introduced by kruskal 18 this approach is both simple and at the same time quite general as an illustration we apply it to the special case of the arbitrage pricing model where the number of factors is pre specified the data appear to be generally in conflict with a five or seven factor representation of the model used by roll and ross 30 when we consider the number of replications of our test and the large number of observations on which it is performed the frequency with which we reject the three factor apm does not lead us to conclude that this model is unrepresentative of security returns further the rejection of the five and seven factor versions is to be expected if the three factor version is correct the paradigm gives insight into the appropriate specification of the model and suggests that there may be a small number of economy wide factors that affect security returns tests of asset pricing models on the basis of observed stock market data have represented a staple of the financial economics literature of the past twenty years the early work is reviewed in the famous paper by jensen 12 and papers by fama and macbeth 6 rosenberg and marathe 31 and roll and ross 30 there has been a great deal of confusion regarding what testable propositions are implied by these models see discussion in roll 29 in this paper we show that at a minimum all asset pricing models yet proposed imply a simple easily testable hypothesis which we refer to as the bilinear hypothesis while specific models may imply further testable propositions if the bilinear hypothesis is rejected the model is inconsistent with the data and should be rejected our test exploits the fact that the economic content of any equilibrium asset pricing model can be expressed in the form of a potentially refutable constraint on the set of parameters of the process generating security returns this constraint specifies that given a set of security specific characteristics there exists a linear relationship common across securities relating expected returns to these

a critical reexamination of the empirical evidence on the arbitrage pricing theory this paper demonstrates that the roll and ross rr and other previously published tests of the apt are subject to several basic limitations there is a general nonequivalence of factor analyzing small groups of securities and factor analyzing a group of securities sufficiently large for the apt model to hold it is found that as one increases the number of securities the number of factors determined increases this increase in the number of factors with larger groups of securities cannot readily be explained by a distinction between priced and nonpriced risk factors as it is impermissible to carry out tests on whether a given risk factor is priced using factor analytic procedures the apt model as exposited by ross 17 18 and extended by huberman 9 has provided the basis of an extensive literature as for example brown and weinstein 1 chen 3 hughes 10 ingersoll 11 jobson 12 reinganum 15 roll and ross rr 16 and shanken 17 to mention but a few it has also been treated in a more general context by chamberlain and rothschild 2 our purpose here is not to comment on this collection of papers many of which are unpublished but to reexamine the evidence presented by rr and point out major pitfalls involved in the empirical methodology employed by them and others who have followed their lead rr claim that on theoretical and more importantly on empirical grounds arbitrage pricing theory apt is an attractive alternative to the capital asset pricing model capm the apt it is argued requires less stringent and presumably more plausible assumptions is more readily testable since it does not require the measurement of the market portfolio and may be better able to explain the anomalies found in the application of the capm to asset returns the acceptability of the apt like that of the capm or any other theory ultimately depends on its ability to explain the relevant empirical evidence our subsequent discussion will show that many of the prqblems associated with the capm are also present in the apt context and that its ability to explain the relevant empirical evidence is not markedly superior moreover it raises questions not only about the rr and related empirical investigations of the apt but also about the testability of that theory in the present state of the art a major part of the problem results from the necessity to break down the universe being analyzed through the apt model this is forced upon the investigator by the fact

portfolio performance evaluation old issues and new insights this article presents a model that provides insights about various measures of portfolio performance the model explores several criticisms of these measures these include the problem of identifying an appropriate benchmark portfolio the possibility of overestimating risk because of market timing ability and the failure of informed investors to earn positive risk adjusted returns because of increasing risk aversion the article argues that these need not be serious impediments to performance evaluation

the empirical foundations of the arbitrage pricing theory abstract this paper uses maximum likelihood factor analysis of large cross sections to examine the validity of the arbitrage pricing theory apt we are unable to explain the expected returns on firm size portfolios although we do explain the expected returns on portfolios formed on the basis of dividend yield and own variance where risk adjustment using the usual capm market proxies fails we also compare alternate versions of the apt and sharply reject the hypothesis that basis portfolios formed to mimic the factors span the mean variance frontier of the individual assets

a comparison of single and multifactor portfolio performance methodologies a comparison of single and multifactor portfolio performance methodologies using value line and size ranked portfolios indicates that although both methodologies provide unbi ased estimates of portfolio performance there are systematic differences in the power of the two methodologies the predictive power of the multifactor methodology is superior for well diversified portfolios but inferior for less diversified portfolios

factor pricing in a finite economy abstract prior theoretical derivations of the arbitrage pricing theory apt bound an aggregate measure of the deviation of mean asset returns from that predicted by a linear pricing equation it is conceivable given this bound that some assets might be badly mispriced by the model in this paper a more intuitive derivation of the factor pricing equation is presented which describes the deviation on an asset by asset basis the deviation is shown to be small for assets in a realistic finite economy and is arbitrarily close to zero for those assets with arbitrarily small size relative to aggregate wealth it follows that the linear pricing equation provides a good approximation for the mean returns of all traded assets

an empirical method of dynamic oligopoly behavior analysis in electricity markets evidence of market power existing in the electricity markets has been empirically revealed but the understanding of the market structure and generation companies gencos strategic behaviors underlying the market power is far from satisfactory this paper presents a theory and method for estimating the conjectural variations of gencos based on these estimates of conjectural variations in an actual electricity market an empirical methodology is also proposed to analyze the dynamic oligopoly behaviors underlying market power this is not only useful for system regulators to analyze the market structure but also to recognize and control the market power accordingly the australia national electricity market is used as the simulation case to test the proposed method

incorporating contemporaneous residual relationships for security prices abstract using a recent procedure developed by jalilvand and kryzanowski 1985 to capture the contemporaneous residual dependencies in a system of regression equations this paper tests the impact of such residual based relationships in explaining security prices utilizing a multi industry sample of securities over two non overlapping periods the empirical findings show that not only are these contemporaneous residual relationships statistically significant but their inclusion significantly improves the explanatory power of the underlying return generating model

the arbitrage pricing theory approach to strategic portfolio planning the well known capital asset pricing model asserts that only a single number an asset s beta against the market index is required to measure risk arbitrage pricing theory asserts that an asset s riskiness hence its average long term return is directly related to its sensitivities to unanticipated changes in four economic variables 1 inflation 2 industrial production 3 risk premiums and 4 the slope of the term structure of interest rates assets even if they have the same capm beta will have different patterns of sensitivities to these systematic factors the central focus of portfolio strategy is the choice of an appropriate pattern of sensitivities this choice will depend upon the economic characteristics of the beneficiary of the portfolio s income in particular upon whether it is more or less concerned with the economic factor risks than the broad average of investors an organization for example may expect to spend less on food than the average investor to the extent that food p

multivariate proxies and asset pricing relations abstract a framework is developed in which inferences can be made about the validity of an equilibrium asset pricing relation even though the central aggregate in this relation is unobservable a multivariate proxy for the true market portfolio consisting of an equal weighted stock index and a long term government bond index is employed in an investigation of the sharpe lintner capm the empirical evidence suggests that we can reject the joint hypothesis that a capm is valid and b multiple correlation between the true market portfolio and proxy assets exceeds 0 7 connections to the equilibrium factor pricing literature are also explored

a new approach to international arbitrage pricing this paper uses a nonlinear arbitrage pricing model a conditional linear model and an unconditional linear model to price international equities bonds and forward currency contracts unlike linear models the nonlinear arbitrage pricing model requires no restrictions on the payoff space allowing it to price payoffs of options forward contracts and other derivative securities only the nonlinear arbitragepricing model does an adequate job of explaining the time series behavior of a cross section of international returns the idea that a few relevant state variables explain expected returns is the main driving force of the seminal papers of merton 1973 and ross 1976 these seminal ideas have been extended to the pricing of international assets by ikeda 1991 ross and walsh 1983 solnik 1974 1983 and stulz 1981 among others the key implication of these arbitrage pricing models is that only risks related to these factors state variables are relevant in determining asset prices testable implications of these international asset pricing models have been derived either by placing restrictions on the payoff structure i e payoffs are linear in factors as in ikeda 1991 ross and walsh 1983 and solnik 1983 or on the joint distributions of the payoffs and state variables as in constantinides 1989 these restrictions lead to the testable implication that expected asset returns are linear in the conditional covariances with the factor payoffs in what follows we refer to these models as linear arbitrage models or linear models

intertemporal arbitrage pricing theory it is shown that the arbitrage pricing theory holds in each infinitesimal period of a continuous trading model under the assumption that dividend payoffs are functionals of factor and idiosyncratic uncertainty this generalizes the one period model s result that the arbitrage pricing theory holds under the assumption that price changes in a given period satisfy a factor structure since instantaneous returns in a multiperiod model are endogenously determined the theory is derived under assumptions that may be viewed as restricting more primitive characteristics of the economy than the assumptions made for the one period model article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

diversification of macroeconomic risk and international integration of capital markets the case of mexico this article tests the arbitrage pricing theory in the context of the unstable macroeconomic years in mexico 1977 87 using information on returns on assets available to domestic investors primarily stocks traded at the local stock exchange an attempt is made to ascertain the extent to which these assets have offered premia for a set of proposed sources of risk the pervasive factors that play an important role in asset pricing in mexico are unexpected inflation unexpected money growth innovations in the standard poor s 500 price series and innovations in the dollar oil price a residual market factor is obtained using the mcelroy and burmeister model given that these risks get premia over and above the riskless rate expected rates of return in mexico have been higher during the years of erratic macroeconomic conditions mexico is not considered to be well integrated with the international capital markets because local sources of risk such as inflation are not priced in the united states whereas international sources of uncertainty such as oil price shocks are priced locally but not in the united states capital markets are becoming increasingly important in developing countries because of the international debt problem it seems unlikely that semi industrial nations will be able to raise substantial amounts of funds in the international financial markets the development and growth of modern domestic capital markets will allow these economies to tap additional savings and to improve the allocation of scarce funds organized and liquid capital markets are a vital factor in promoting overall development they provide a means of allocating capital to alternative private and public projects and they furnish essential information for evaluating investment undertakings ross 1978 black 1988

asset financing with credit risk abstract this paper develops a model for the unified valuation of all forms of real asset financing such as bank loans leases securitization vehicles and credit guarantees secured by assets that generate a stochastic service flow to the operator or a rental stream to the lessor and depreciate over a finite economic life to their scrap value examples include mobile equipment such as aircraft railroad equipment ships trucks and trailers as well as energy generation assets heavy factory equipment and construction equipment in the event of obligor default after a repossession delay and incurring costs of repossession maintenance re marketing and re deployment the lender repossesses the asset and sells it on the secondary market and is thus subject to the risk of decline in the market value of the asset the model we develop in this paper treats all forms of asset financing in a unified fashion as contingent claims on the collateral asset and the credit of the borrower as an application we estimate the collateral asset model on historical secondary market data for aircraft values and calibrate the financing model to the enhanced equipment trust certificates eetcs issued in 2007 by continental airlines and secured by a fleet of new aircraft we then apply the calibrated model to value private market financing including bank loans leases and credit guarantees consistently with the capital market financing and assess the impact of repossession delays on credit spreads this analysis leads to a policy insight suggesting that bankruptcy laws limiting asset repossession delays lead to lower costs of asset financing

some empirical tests of the theory of arbitrage pricing we estimate the parameters of ross s arbitrage pricing theory apt using daily return data during the 1963 78 period we compare the evidence on the apt and the capital asset pricing model capm as implemented by market indices and find that the apt performs well the theory is further supported in that estimated expected returns depend on estimated factor loadings and variables such as own variance and firm size do not contribute additional explanatory power to that of the factor loadings

tests of asset pricing with time varying expected risk premiums and market betas tests of asset pricing models are developed that allow expected risk premiums and market betas to vary over time these tests exploit the relation between expected excess returns and current market values using weekly data for 1963 through 1982 on ten common stock portfolios formed according to equity capitalization a single risk premium model is not rejected if the expected premium is time varying and is not constrained to correspond to a market factor conditional mean variance efficiency of a value weighted stock index is rejected and the rejection is insensitive to how much variability of expected risk premiums is assumed financial economists have studied valuation models in which securities expected returns are related to the covariances of unanticipated returns with the return on the market portfolio or with other risk factors empirical tests of such models typically have employed unconditional sample moments of returns recent studies provide mounting evidence that expected returns change over time with information such evidence presents an opportunity to develop new approaches for evaluating and implementing asset pricing models that exploit this time variation this paper presents new tests of financial valuation models in which expected returns are allowed to vary over time time series of relative

the pricing of interest rate risk evidence from the stock market this paper addresses the issue of whether firms are required to pay an ex ante premium to investors for bearing the risk of interest rate changes a two factor apt model with the market and changes in the yield on long term government bonds as factors is employed the paper shows that empirically most of the interest sensitive stocks are in the utility industries and that there is reasonable evidence that the interest factor is priced in the sense of the apt several sources for the interest sensitivity are considered and regulatory lags are focused on as a likely candidate some firms exhibit ex post sensitivity in their stock returns to unanticipated changes in interest rates are these firms required to pay investors ex ante for bearing this risk of interest rate changes the framework for examining pricing of unanticipated interest rate changes is a two factor apt model with the market and changes in the yield on long term government bonds as factors the issue is whether the interest rate change premium is significant to study this the paper uses full information maximum likelihood fiml estimation on groups of twenty five individual firms with both cross equation constraints and withinequation nonlinear constraints on the parameters as mandated by the apt model whether the risk of unanticipated changes in interest rates is priced in the market is of particular interest with regard to regulated firms regulated firms especially electric utilities turn out to comprise the big majority of firms that are sensitive to unanticipated interest rate changes after some preliminary investigation the analysis focuses on electric utilities much empirical work on the apt relies on factor analysis e g roll and ross 30 bower bower and logue 5 use factor analysis in comparing the apt and the capm to explain utilities returns the present paper however uses observable variables at the macro level chan chen and hsieh cch 7 and chen roll and ross crr 8 also examine apt models with specific macroeconomic factors cch and crr use a traditional fama macbeth type of cross sectional estimation approach in the premia calculations rather than a fiml approach gibbons and stambaugh have applied fiml techniques to models using only the market as an explanatory variable gibbons 20 used a noniterative algorithm on portfolios of firms equivalent to a two step cross sectional approach stam

a scenario simulation approach for market power analysis in hydrothermal systems this paper focuses on markets based on physical bilateral contracts combined with a power exchange px the main feature to be analyzed is the behavior of the hydrothermal system where one or more companies have a big reservoir with capacity for inter annual regulation in this work inter annual regulation means the ability of a reservoir to allocate water from consecutive years the use of the reservoirs in a context of a power exchange market with competition is the main objective of this study results on the chilean central interconnected system using stochastic dynamic programming are presented and discussed

the sampling error in estimates of mean variance efficient portfolio weights this paper presents an exact finite sample statistical procedure for testing hypotheses about the weights of mean variance efficient portfolios the estimation and inference procedures on efficient portfolio weights are performed in the same way as for the coefficients in an ols regression ols t and f statistics can be used for tests on efficient weights and when returns are multivariate normal these statistics have exact t and f distributions in a finite sample using 20 years of data on 11 country stock indexes we find that the sampling error in estimates of the weights of a global efficient portfolio is large

additional evidence on integration in the canadian stock market this paper reexamines the integration of the canadian and u s stock markets in the 1977 86 period that is relatively free from capital controls the study employs both the capm and the apt frameworks under both models the evidence is consistent with segmentation in the 1977 81 subperiod but supports integration in the 1982 86 subperiod using the apt framework we also find that the canadian stocks interlisted on the u s exchanges and nasdaq are priced in an integrated market and segmentation is predominant for the non interlisted canadian stocks in a study using an international capm framework jorion and schwartz 1986 find strong evidence of segmentation in the pricing of canadian stocks relative to a north american market comprising the canadian and u s stock markets the rejection of integration holds for canadian stocks that are interlisted on the u s stock exchanges and nasdaq as well as for domestic canadian stocks that are listed only on the canadian stock exchanges their results are surprising since the canadian and u s economies are highly integrated and the structure and regulation of security markets in the two countries are similar as well the canadian stocks interlisted on the u s stock exchanges list under the same regulation as the domestic u s stocks thus ex ante we would expect the canadian and u s stock markets to be integrated especially for the interlisted stocks 1 this study reexamines the integration in the canadian market employing both the capm and the apt frameworks since tests of market integration are joint tests of a specified model and market integration a relevant question is whether the two models produce different inferences pertaining to the integration issue in addition we explore this issue in a period that is

portfolio selection and asset pricing three parameter framework idiosyncratic security risks are modelled as following a joint spherical distribution characterized by a mean vector and a generalized covariance matrix skewness is generated by a single factor for the whole economy but upon which different securities have different loadings this results in three fund separation two funds to span the spherical risk and one more fund to span the additional skewness risk a three parameter normative portfolio analysis that allows short sales restrictions is developed in addition a three parameter capital asset pricing model is provided

a simple approach to arbitrage pricing theory the following sections are included introductionarbitrage pricingdiscussionreferencesdiscussion notes on the arbitrage pricing theorypure arbitrage pricing theoryapproximate arbitrage and the aptapproximate factor modelsthe competitive equilibrium version of the aptconclusionnotereferences this abstract was borrowed from another version of this item

reference variables factor structure and the approximate multibeta representation the arbitrage pricing theory apt implies that if asset returns have a factor structure then an approximate multibeta representation holds with respect to the factors as reference variables this paper assumes that asset returns satisfy a factor structure and derives a condition under which the approximate multibeta representation holds with respect to a set of reference variables which may not be the factors this condition is that the regression matrix of the reference variables on the factors is nonsingular implications for the testability of the apt are also discussed

posterior predictive and utility based approaches to testing the arbitrage pricing theory abstract to provide a framework for judging the economic significance of departures from the arbitrage pricing theory we adopt a utility based metric based on optimal portfolio choices this measure is examined using both predictive and posterior analysis our predictive analysis shows very large and economically significant departures from the model restrictions however the high level of parameter uncertainty suggests that we cannot conclusively either affirm or reject the apt our conclusions differ markedly from other studies which employ traditional significance testing procedures and in many instances fail to reject the apt restrictions

credit chains and bankruptcy propagation in production networks abstract we present a simple model of a production network in which firms are linked by supplier customer relationships involving extension of trade credit our aim is to identify the minimal set of mechanisms which reproduce qualitatively the main stylized facts of industrial demography such as firms size distribution and at the same time the correlation over time and across firms of output growth and bankruptcies the behavior of aggregate variables can be traced back to the direct firm firm interdependence in this paper we assume that the number of firms is constant and the network has a periodic static structure but the framework allows further extensions to investigate which network structures are more robust against domino effects and if the network is let to evolve in time which structures emerge spontaneously depending on the individual strategies for orders and delivery

the current state of the arbitrage pricing theory this paper provides a simple proof of a recent theorem presented by reisman 1992 concerning the use of proxies for the factors in the return generating process of the arbitrage pricing theory apt in the single factor case the theorem asserts that any variable correlated with the factor can serve as the benchmark in an approximate apt expected return relation the significance of this result is considered and a new direction for empirical work on arbitrage pricing is outlined given a factor model for an infinite sequence of asset returns ross 1976 showed that the absence of arbitrage implies an approximate linear relation between expected returns and the factor betas ross assumed that returns conform to a strict factor structure i e a factor model with uncorrelated disturbances but noted that this condition could be weakened in deriving the arbitrage pricing theory apt nonetheless statistical methods based on the strict factor model assumption dominated the early empirical work on the apt at first glance the requirement of a strict factor structure appeared to impose a strong restriction on the sets of factors that could be used as a benchmark for measuring systematic risk shanken 1982 demonstrated though that virtually any variables could serve as the factors in a welldefined strict factor model one need only repackage an initial finite set of assets into an equivalent set of portfolios in order to fundamentally alter the associated factor space 2 thus the statistical assumptions underlying the apt cannot by themselves characterize the economically relevant components of returns chamberlain and rothschild 1983 shifted attention away from strict factor structures by proving that the apt holds more generally if returns conform to an approximate factor model 3 in this case the disturbances need

international arbitrage pricing theory an empirical investigation in this paper we test the arbitrage pricing theory apt in an international setting inter battery factor analysis is used to estimate the international common factors and the chow test is used in testing the validity of the apt our inter battery factor analysis results show that the number of common factors between a pair of countries ranges from one to five and our cross sectional test results lead us to reject the joint hypothesis that the international capital market is integrated and that the apt is internationally valid our results however do not rule out the possibility that the apt holds locally or regionally in segmented capital markets finally the basic results of both the inter battery factor analysis and the cross sectional tests are largely invariant to the nume raire currency chosen numerous authors notably solnik 21 grauer litzenberger and stehle 11 and stulz 24 have derived various versions of the international asset pricing model iapm under alternative views of the structure of international capital markets however only a few serious attempts have been made to test various versions of the iapm these tests are largely inconclusive see solnik 20 and stehle 23 apart from the problem stressed by roll 16 of identifying the world market portfolio previous tests of the iapms suffer from the technical problem of aggregating assets of national investors using different numeraire currencies differences in the numeraire arise from differences in consumption baskets in an environment characterized by exchange rate uncertainty in a fruitful attempt to extend the arbitrage pricing theory apt of ross 18 to an international setting solnik 22 derives an international arbitrage pricing theory which is largely devoid of the aforementioned difficulties and thus more amenable to empirical testing 1 as shown by solnik testability of the apt in an

arbitrage pricing theory as a restricted nonlinear multivariate regression model iterated nonlinear seemingly unrelated regression estimates by replacing the unknown random factors of factor analysis with observed macroeconomic variables the arbitrage pricing theory apt is recast as a multivariate nonlinear regression model with across equation restrictions an explicit theoretical justification for the inclusion of an arbitrary well diversified market index is given using monthly returns on 70 stocks iterated nonlinear seemingly unrelated regression techniques are employed to obtain joint estimates of asset sensitivities and their associated apt risk prices without the assumption of normally distributed errors these estimators are strongly consistent and asymptotically normal with the additional assumption of normal errors they are also full information maximum likelihood estimators classical asymptotic nonlinear nested hypothesis tests are supportive of the apt with measured macroeconomic factors

an explicit bound on individual assets deviations from apt pricing in a finite economy abstract ross s arbitrage pricing theory apt is a tractible and reasonable alternative to the mean variance model nonetheless understanding of the theory has been obscured by the complexity of the sequence economy models used for motivation by contrast we give a simple and direct derivation of the apt in a finite economy using an explicit bound on the deviations from apt prices across assets a coarse calculation shows that theoretical deviations from apt pricing are negligible in our economy

data frequency and the number of factors in stock returns abstract determining the number of factors that explain stock returns plays an important role in empirical tests of the arbitrage pricing theory this paper examines the sensitivity of the number of factors to different data frequencies using daily weekly and monthly returns the empirical results are consistent with the null hypothesis that the number of factors is the same for different data frequencies once daily returns are adjusted for nonsynchronous trading the evidence also identifies only one or two factors

the seasonal stability of the factor structure of stock returns this paper investigates the month by month stability of a daily returns and correlation coefficients of stock returns b correlation and covariance matrices c number of return generating factors and d the apt pricing relationship the results show that there is a january effect and a small firm effect in stock returns correlation matrices are more stable than covariance matrices but both types of matrices are not stable across months and across the sample groups the number of return generating factors is rather stable most of the time and for most of the sample groups but there is some significant instability that is related to the average correlation coefficients among stocks the apt pricing relationship does not seem to be supported by the two stage process using the maximum likelihood factor analysis the seasonality of common stock returns has received considerable attention in financial economics research studies by officer 23 rozeff and kinney 29 gultekin and gultekin 11 and others have investigated the stock returns of the u s and other countries on a monthly basis they generally have found that on average january returns are significantly higher than the returns for other months banz 1 and reinganum 25 26 have found abnormally high returns in small market value firms and keim 17 has related this to the first few trading days of january schwert 30 points out the current difficulty of explaining these empirical regularities and the need for further investigations several studies have examined seasonality in risk premiums rozeff and kinney 29 found that seasonality appeared in the risk premiums obtained from a twoparameter capm and that january displayed a relatively large risk premium compared with the other months keim 16 also found seasonality in the risk premiums more recently tinic and west 32 examined the risk premiums of the two parameter capm and observed the previously reported seasonality and high january premium they also found that january is the only month in which there is a consistently positive statistically significant relationship between expected return and risk very recently using the two stage procedure with the

general factor models and the structure of security returns based on markowitz s pioneering study 40 sharpe 56 and lintner 38 advanced the first positivist formulations of the capital asset pricing model capm their models were subsequently refined by mossin 45 fama 15 black 1 and others even though the capm has been studied extensively it has not been empirically validated according to roll 48 the capm cannot be tested in an unambiguous fashion because of a number of intractable measurement and computational difficulties and the joint nature of the hypotheses to be tested

systemic risk in financial systems we consider default by firms that are part of a single clearing mechanism the obligations of all firms within the system are determined simultaneously in a fashion consistent with the priority of debt claims and the limited liability of equity we first show via a fixed point argument that there always exists a clearing payment vector that clears the obligations of the members of the clearing system under mild regularity conditions this clearing vector is unique next we develop an algorithm that both clears the financial system in a computationally efficient fashion and provides information on the systemic risk faced by the individual system firms finally we produce qualitative comparative statics for financial systems these comparative statics imply that in contrast to single firm results even unsystematic nondissipative shocks to the system will lower the total value of the system and may lower the value of the equity of some of the individual system firms

equilibrium factor pricing with heterogeneous beliefs this paper develops an equilibrium factor pricing theory when investors have heterogene ous beliefs about asset payoffs generated by the ross linear factor model investors receive private information about the unknown parameters of the payoff process they use this private information and equilibrium prices to predict asset payoffs the paper de velops a closed form price function for a noisy rational expectations equilibrium and relates it to the general solution even though we allow for a large number of investors diversity of beliefs and parameter uncertainty both persist in equilibrium we show that investors beliefs about expected payoffs are approximately linear in the asset s betas thus establishing the apt as investors prefer to hold high information assets in equilib rium the relative weight of these assets in the apt pricing bound is higher the reverse is true for low information assets

yes the apt is testable the arbitrage pricing theory apt has been proposed as an alternative to the meanvariance capital asset pricing model capm this paper considers the testability of the apt and points out the irrelevance for testing of the approximation error we refute shanken s objections including his assertion that roll s critique of the capm is applicable to the apt we also explain the testability of the apt on subsets and we explore the relationship between the apt and the capm the arbitrage pricing theory apt has been the subject of extensive research efforts since it was introduced by ross 36 37 the research has included theoretical papers and a growing empirical literature 2 nonetheless there seems to be some confusion in the literature about the relation between the theoretical underpinnings of the apt and its empirical tests this paper is an attempt to alleviate the confusion to illustrate the issues and to provide a focus section i of this paper is devoted to examining and refuting some points raised in shanken 40 which considers the testability of the apt the underlying premise of the apt is that asset returns ri are generated by a factor model of the form

multi beta capm or equilibrium apt a reply in their influential empirical paper roll and ross 11 state we think that in many discussions of the capm scholars were actually thinking of the apt and of process 1 the factor model with just a single factor in light of recent developments in the asset pricing literature i think it can now meaningfully be suggested that in many discussions of the apt scholars may have actually been thinking of a multi beta interpretation of the capm indeed much can be said in support of each of these perspectives for a single paradigm is emerging which integrates fundamental aspects of both the capm and the apt broadly speaking the equilibrium capm paradigm emphasizes the role of covariance between asset returns and an endogenous preference based aggregate while the arbitrage apt paradigm focuses on the covariance between asset returns and factors in the return generating process the emerging equilibrium factor paradigm encompasses each of these relations as well as a third covariance between the factors and the equilibrium aggregate my thesis in shanken 17 was that i the arbitrage paradigm has not produced a refutable hypothesis and that ii recognition of the role of the factor aggregate covariance relation appears to be essential if positive economic significance is to be attributed to asset pricing empirical work dybvig and ross d r attempt to resolve the empirical indeterminacy of the arbitrage paradigm by appealing to the condition that residual variance should not be too large i explain in section ii that this condition is inherently ambiguous from an empirical perspective and does not permit the formulation of a precise testable implication the equilibrium factor models which d r discuss do yield testable restrictions on parameters in the return generating process however consistent with my second point above these restrictions involve joint hypotheses that cannot be verified without observing the entire universe of assets thus contrary to their claim considerations similar to those in roll s 10 critique are indeed relevant to the testing of these models this and other similarities between the equilibrium apt and the capm are discussed in section iii i begin by clarifying some basic terminology

real business cycles in this paper we demonstrate how certain very ordinary economic principles lead maximizing individuals to choose consumption production plans that display many of the characteristics commonly associated with business cycles our explanation is entirely consistent with i rational expectations ii complete current information iii stable preferences iv no technological change v no long lived commodities vi no frictions or adjustment costs vii no government viii no money and ix no serial dependence in the stochastic elements of the environment we also provide a completely worked out example of the type of artificial economy we have in mind the time series properties of the example exhibit some major features of observed business cycles although this type of model may not be capable of explaining all of the regularities in actual business cycles we believe that it provides a useful well defined benchmark for assessing the relative importance of factors e g monetary disturbances

government bond returns measurement of interest rate risk and the arbitrage pricing theory empirical tests are reported for ross arbitrage pricing theory using monthly data for u s treasury securities during the 1960 1979 period we find that mean returns on bond portfolios are linearly related to at least two factor loadings multivariate test results however are not consistent with the apt our sample data in the u s treasury securities market are also not consistent with either version of the capm one monthahead forecasts of excess returns using factor generating models are compared with corresponding naive predictions or predictions using the market model with various