real exchange rates under the recent float unequivocal evidence of mean reversion standard multivariate tests of long run ppp may reject nonstationarity when a single real exchange rate series is stationary we apply a test where the null hypothesis is violated only when all series are stationary and reject nonstationarity for real dollar rates

sticky prices and deviations from the law of one price evidence from mexican micro price data abstract this paper uses a novel dataset of weekly sampled store level prices to study the impact of sticky prices on the volatility and persistence of intranational deviations from the law of one price lop the volatility of lop deviations is found to be increasing both on the distance separating two locations and on the degree of price stickiness sticky prices are also found to be systematically related to the persistence of lop deviations half lives of lop deviations are systematically larger for goods with stickier prices these observations are shown to accord well with the predictions of a dynamic general equilibrium model featuring real market segmentation and calvo pricing i also find evidence of remarkably fast convergence to the lop average half lives of lop deviations are in the order of 3 6 weeks and show that previously reported convergence estimates may be afflicted by a positive temporal aggregation bias

compatibility and bundling of complementary goods in a duopoly this paper presents a simple model of compatibility and bundling in industries where consumers assemble several necessary components into a system that is close to their ideal the authors show that for a wide range of parameters firms will choose to produce compatible components but will offer discounts to consumers who purchase all components from the same firm however firms would be better off if they could commit not to provide such discounts furthermore the equilibrium tends to involve socially excessive bundling finally mixed bundling strategies tend to increase the range of parameters over which socially excessive standardization occurs copyright 1992 by blackwell publishing ltd

optimal bundling of technological products with network externality for many high tech and internet related products utility to consumers depends in part on the size of the user base a phenomenon called network externality a firm with a portfolio of these and other products that are often asymmetric in their degree of network externality or marginal cost may have to look beyond the traditional strategies of pure components pure bundling and mixed bundling one such strategic alternative in a two product case would be a so called mixed bundling 1 under which the bundle and product 1 are offered but the other product can only be purchased in a bundled form the purpose of this study is to compare and contrast the impact of such asymmetry or symmetry in direct network externality and cost on the choice of bundling strategies we model a monopolist firm that has a product in each of two categories and faces heterogeneous consumers results suggest that pure bundling is more profitable when both products have low marginal costs or high network externality whereas pure components or mixed bundling 1 is more profitable when the products diverge in their costs and network externality e g only one product has network externality traditional mixed bundling is optimal in other instances

installed base and compatibility innovation product preannouncements and predation a good is often more valuable to any user the more others use compatible goods the authors show that this effect may inhibit innovation if an installed base exists and transition to a new standard must be gradual early adopters bear a disproportionate share of transient incompatibility costs this can produce excess inertia the installed base however is stranded if the new standard is adopted this may create excess momentum these dynamic effects have strategic implications temporary price cutting can permanently prevent entry and product preannouncements can be critical in innovation these strategic actions have ambiguous welfare effects

real exchange rate behavior abstract using random simulations with artificial data with identical sample characteristics to the long sample exchange rate data employed by lothian and taylor lothian j r and taylor m p 1996 the recent float from the perspective of the past two centuries journal of political economy 104 488 509 we show that standard unit root tests have extremely low power over sample sizes corresponding to the recent float the probability of rejecting the null hypothesis when it is false is extremely low with 20 years or even 50 years of data and only reaches an acceptable level over much longer spans

bundling as an entry barrier in this paper we look at the case for bundling in an oligopolistic environment we show that bundling is a particularly effective entry deterrent strategy a company that has market power in two goods a and b can by bundling them together make it harder for a rival with only one of these goods to enter the market bundling allows an incumbent to credibly defend both products without having to price low in each the traditional explanation for bundling that economists have given is that it serves as an effective tool of price discrimination by a monopolist although price discrimination provides a reason to bundle the gains are small compared with the gains from the entry deterrent effect i introduction in this paper we look at the case for bundling in an oligopolistic environment we show that bundling is a particularly effective entry deterrent strategy a company that has market power in two goods a and b can by bundling them together make it harder for a rival with only one of these goods to enter the market bundling allows an incumbent to defend both products without having to price low in each while it is still possible to compete by offering a rival bundle a monopolist can significantly lower the potential profits of a one product entrant without having to engage in limit pricing prior to entry we also show that bundling continues to be an effective pricing tool even if entry deterrence fails or if there is already an existing one product rival a company with a monopoly in product a and a duopoly in product b makes higher profits by selling an a b bundle than by selling a and b independently leveraging market power from a into b and accepting some one product competition against the bundle is better than using the monopoly power in good a all by itself since bundling mitigates the impact of competition on the incumbent an entrant can expect the bundling strategy to persist even without any commitment the traditional explanation for bundling that economists have given is that it serves as an effective tool of price discrimination by a monopolist see stigler 1968 adams and yellen

smooth breaks and non linear mean reversion post bretton woods real exchange rates the recent literature on purchasing power parity ppp has emphasized the role of two phenomena that may lead to the rejection of the ppp hypothesis structural breaks and non linear adjustment induced by transaction costs these two hypotheses are analyzed separately in the literature we develop tests for unit roots that account jointly for structural breaks and non linear adjustment structural breaks are modeled by means of a fourier function that allows for infrequent smooth temporary mean changes and is hence compatible with long run ppp nonlinear adjustment is modeled by means of an estar model our tests present good finite sample properties the tests are applied to a set of 15 oecd countries rers and are able to reject the null of a unit root in 14 cases the breaks are usually associated with the great appreciation and later depreciation of the dollar in the 1980s and the estar adjustment appears to play an important role

consumption import prices and the demand for imported consumer durables a structural econometric investigation this paper derives and estimates a rational expectations optimizing model of the demand for imported consumer durable goods the author is unable to reject the essential empirical implications of the model and obtain sensible estimates of the price and income elasticities of the demand for imported consumer durables copyright 1996 by mit press

real and nominal exchange rates in the long run an empirical investigation abstract this paper reports on econometric tests of the hypothesis that purchasing power parity holds as a long run relationship using data on eight industrialized countries during the flexible exchange rate period the empirical work proceeds by i testing whether nominal exchange rates and relative price levels are co integrated and ii conducting impulse response analysis of long run exchange rate and relative price level changes to explain the data keynesian models suggest that shocks during the estimation period were due principally to exogenous shifts in aggregate demand while equilibrium models suggest that monetary factors have been relatively more important

intraconnectivity and interconnectivity when value creation may reduce profits this paper analyses firms decisions to provide connectivity to their customers we distinguish between intraconnectivity the ability of one firm s customers to connect to each other and interconnectivity the ability of one firm s customers to connect with another firm s customers the profitability implications of allowing connectivity are not a straightforward consequence of the consumer value of connectivity because connectivity affects not only the customer value but also the intensity of competition by creating or changing network externality we find that if sales are driven by brand switching rather than by category expansion a firm may find it optimal not to provide intraconnectivity even if providing it is not costly and may find it optimal to provide interconnectivity even at a cost exceeding the consumer value of connectivity on the other hand if category expansion is possible providing intraconnectivity may be profitable in this case either the equilibrium intraconnectivity provision may be asymmetric or both firms may find it individually optimal to provide intraconnectivity under certain conditions in the latter case the firms choice of intraconnectivity is a prisoner s dilemma game

cointegration aggregate consumption and the demand for imports a structural econometric this paper uses a two good version of hall s 1978 representative agent permanent income model to derive a structural import demand equation for nondurable consumer goods under the identification restriction that taste shocks are stationary the model is shown to imply that log imports log domestic goods and the log relative price of imports are co integrated the data decisively reject the null hypothesis that imports the relative price of imports and the consumption of home goods are not co integrated we employ the non linear least squares technique recently proposed by phillips and loretan 1990 to estimate the parameters of the import demand equation the long run price elasticity of import demand is estimated to be 0 95 the elasticity of import demand with respect to a permanent increase in real spending is estimated to be 2 20 these estimates fall within the range reported in studies by helkie and hooper 1986 cline 1989 and the many studies surveyed by goldstein and kahn 1985 the message of this paper is that at least for non durable consumer goods it is possible to interpret the traditional import demand equation as a co integrating regression and to interpret the price and expenditure elasticities estimated from such a trade equation as a co integrating vector estimates of the co integrating vector can be used to recover estimates of the utility parameters of the representative household the similarity between the ols and phillips loretan estimates of the parameters suggests that the simultaneous equation bias is not large this abstract was borrowed from another version of this item

real exchange rate behavior the recent float from the perspective of the past two centuries using annual data spanning two centuries for dollar sterling and franc sterling real exchange rates we find strong evidence of mean reverting real exchange rate behavior using simple stationary autoregressive models estimated on prefloat data we easily outperform nonstationary real exchange rate models in dynamic forecasting exercises over the recent float such stationary univariate equations explain 60 80 percent of the in sample variation in real exchange rates although the degree of short run persistence may be high the econometric estimates imply a half life of shocks to the real exchange rate of about 6 years for dollar sterling and a little under 3 years for franc sterling

the dynamic effects of bundling as a product strategy several key questions in bundling have not been empirically examined in marketing is mixed bundling more effective than pure bundling or pure components does correlation in consumer valuations make bundling more or less effective does bundling serve as a complement or substitute to network effects to address these questions we develop a consumer choice model from microfoundations to capture the essentials of our setting the handheld video game market we provide a framework to understand the dynamic long term effects of bundling on demand the primary explanation for the profitability of bundling relies on homogenization of consumer valuations for the bundle allowing the firm to extract more surplus we find that bundling can be effective through a novel and previously unexamined mechanism of dynamic consumer segmentation which operates independent of the homogenization effect and can in fact be stronger when the homogenization effect is weaker we also find that bundles are treated as separate products distinct from component products by consumers sales of both hardware and software components decrease in the absence of bundling and consumers who had previously purchased bundles might delay purchases resulting in lower revenues we also find that mixed bundling dominates pure bundling and pure components in terms of both hardware and software revenues investigating the link between bundling and indirect network effects we find that they act as substitute strategies with a lower relative effectiveness for bundling when network effects are stronger

real exchange rate assessment in the gcc countries a trade elasticities approach this article adopts new panel econometric methods to assess real exchange rate alignment with economic fundamentals in the countries of the gulf cooperation council gcc using a theoretical approach popularized by paul krugman in the late 1980s results from panel econometric applications of the krugman model yield low levels of real exchange rate undervaluation in the gcc countries although indicating persistence of undervaluation albeit statistically low into the medium term they also show that the recent real exchange rate undervaluation could be characterized as due to short run frictions and adjustment costs associated with continued depreciation of the us dollar to which gcc countries currencies are pegged further failure to find supporting evidence for the marshall lerner condition underscores the propriety of using fiscal policy rather than exchange rate policy to address recent inflationary pressures and help resolve lingering global financial imbalances

research note competitive bundling and counterbundling with generalist and specialist firms bundling which is the practice of selling two or more products or services in a package is a pervasive marketing practice and is often used as a strategic competitive tool however there has not been enough consideration of competitive bundling situations in which exit of a competitor is not a concern in this paper we address this issue by identifying conditions under which strategic competitors may or may not resort to bundling when competitor exit considerations are absent we study competition between a multiproduct generalist firm and two single product specialist firms in two product categories one of which has undifferentiated products and the other has differentiated products in our model the specialist firms can form an alliance to bundle their products in competing with the generalist firm in contrast to the previous literature we find that concurrent bundling by competitors if it occurs in equilibrium is profitable we also find that when one competitor bundles and the other does not the bundling firm gains a greater share of customers and makes a higher profit however when conditions favor counterbundling by a competitor such counterbundling helps the competitor retain its customers finally we note that under other market conditions concurrent bundling by competitors escalates price competition to the extent that retaining customers through bundling is not profitable in such a case we show that strategic competitors are better off having asymmetric product lines with one competitor bundling and the other selling unbundled

income equivalence and a proposed resource rent charge abstract we demonstrate the equivalence of various income based charges when perfect certainty prevails as well as deviations from equivalence under uncertainty some of these equivalences are known but the derivations of others such as cases for two types of free equity are not these equivalences lay the foundation for a proposed accrued rent charge arc as an alternative to resource rent taxes rrt both as proposed and implemented we argue that the arc may be preferred to the rrt because the timing of returns to investors owners of reproducible capital and owners of natural assets coincide that is returns accrue to owners of natural assets earlier in time with the arc relative to the rrt in addition we argue that while both charges are inefficient when there is uncertainty the arc may be relatively more administratively and economically efficient finally we use simulations to compare the arc to the rrt and to standard income charges and discuss the results

optimal bundling and pricing under a monopoly contrasting complements and substitutes from independently valued products we develop an analytical model of contingent valuations and address two questions of import to a monopolist i should a given pair of complements or substitutes be sold separately pure components together pure bundling or both mixed bundling and at what prices ii how do optimal bundling and pricing strategies for complements and substitutes differ from those for independently valued products we find that the combination of marginal cost levels and the degree of complementarity or substitutability determines which of the three bundling strategies is optimal complements and substitutes should typically be priced higher than independently valued products

mixed bundling of two independently valued goods this paper develops analytical results and insights for the mixed bundling problem of pricing a product line consisting of two component goods with valuations distributed uniformly and independently in 0 a1 and 0 a2 respectively with a1 a2 and a bundle of the two goods this setting has previously been considered analytically intractable by deriving component good prices as exact algebraic functions of the optimal bundle price i reduce the multiproduct pricing problem to a univariate nonlinear optimization problem in the bundle price when the two component goods are sufficiently asymmetric in valuations the optimal solution is partial mixed bundling one component good is not sold separately for which i derive exact conditions and optimal prices an exact analytical solution is also given for mixed bundling of two information goods component goods with zero marginal costs for the general case i derive a closed form approximation of the optimal bundle price pb 0 5724w1 0 5695w2

long run purchasing power parity in the 1920s abstract this paper presents an empirical analysis of long run purchasing power parity ppp during the 1920s float using recently developed methodology on the cointegration of economic time series our results are generally supportive of ppp as a long run equilibrium condition on which exchange rates tended to converge over the period for dollar sterling however there is some evidence of a non stationary drift away from fundamentals during the last year or so before britain s return to the gold standard perhaps due to speculation our results also appear to reconcile some apparently conflicting evidence in the literature

network externality compatibility choice and planned obsolescence this paper attempts to provide a formal theory of planned obsolescence based on incompatible technologies in the presence of network externalities the author explores how a monopolist s ability to make the new product incompatible with the old version of a product constrains the optimal dynamic behavior of the monopolist the social optimum and the market equilibrium are compared finally the possibility of quality distortion is considered as a commitment mechanism to the future compatibility choice copyright 1994 by blackwell publishing ltd

technology adoption in the presence of network externalities we analyze technology adoption in industries where network externalities are significant the pattern of adoption depends on whether technologies are sponsored a sponsor is an entity that has property rights to the technology and hence is willing to make investments to promote it key findings include the following 1 compatibility tends to be undersupplied by the market but excessive standardization can occur 2 in the absence of sponsors the technology superior today has a strategic advantage and is likely to dominate the market 3 when one of two rival technologies is sponsored that technology has a strategic advantage and may be adopted even if it is inferior 4 when two competing technologies both are sponsored the technology that will be superior tomorrow has a strategic advantage

gaussian demand and commodity bundling in an important and widely cited essay adams and yellen 1976 examine the use of package selling as a price discrimination device they consider a monopolist producing two goods with constant unit costs and facing buyers with diverse tastes the marginal utility of a second unit of either good is assumed to be zero for all buyers the two goods are independent in demand for all buyers so that any buyer s reservation price for the first unit of either good is independent of the market price of the other thus the maximum amount any buyer would pay for a bundle consisting of one unit of each good is the sum of the two reservation prices and buyers are completely described by the values of those two prices 2 resale markets are assumed away in order to obtain comparative results for alternative pricing strategies the distribution of reservation prices in the adams yellen framework is assumed to be bivariate normal implications of gaussian demand are explored pure bundling is shown to operate by reducing buyer diversity thus facilitating the capture of consumers surplus it generally makes buyers worse off than unbundled sales it is more profitable if average reservation prices are high enough mixed bundling combines advantages of both pure bundling and unbundled sales and it is generally strictly more profitable than either bundling which treats goods symmetrically seems most attractive under symmetric reservation price distributions i am indebted to severin borenstein for superb research assistance to the ford motor company for research support through a grant to m i t and to the harvard economics department for housing me as a visiting scholar while most of this research was performed of course only i can be held responsible for this essay s shortcomings 1 the first clear recognition of this possibility seems to have been by stigler 1968 but also see burstein 1960 2 paroush and peles 1981 relax the assumption that consumers purchase at most one unit of each good but they consider only two types of buyers both with linear demand functions they retain the assumption that demands are independent for all buyers telser 1979 and phillips 1981 use different frameworks to analyze bundling policies spence 1980 explores the relation between bundling across commodities as here and bundling multiple units of the same

differences in income elasticities and trends in real exchange rates abstract one might expect that differences in income elasticities in trade and or differences in growth rates among countries would give rise to strong secular trends in real exchange rates for example fast growing countries might need steady depreciation to get the world to accept their growing exports in fact however income elasticities are systematically related to growth rates by the 45 degree rule under which fast growing countries appear to face high income elasticities of demand for their exports while having low income elasticities of import demand the net effect of this relationship between elasticities and growth rates is that secular trends in real exchange rates are much smaller than one might otherwise have expected relative ppp holds fairly well this paper documents the existence of a 45 degree rule and suggests an explanation in terms of increasing returns and product differentiation

engel s law and cointegration a time series counterpart of engel s law is that the expenditure share on food declines as the economy grows the main purpose of this paper is to test whether houthakker s addilog utility function can simultaneously explain this time series observation and cross sectional observations concerning engel s law ogaki and park s cointegration approach is used to estimate parameters of the utility function from time series data total expenditure elasticities implied by the estimated addilog utility function are compared with estimates of the elasticities from cross sectional data

a strategic motivation for commodity bundling the analytical literature on commodity bundling explains the practice of selling two or more differentiated products in a single package as a surrogate for direct price discrimination in contrast this paper shows that imperfect competition creates a strategic incentive to bundle the profitability of bundling whether it adversely affects rival producers and whether it yields an overall efficiency gain depends inter alia on the nature of product market competition the role of complementarity in explaining why firms bundle is also explored copyright 1990 by blackwell publishing ltd

purchasing power parity over two centuries strengthening the case for real exchange rate stability a reply to cuddington and liang cuddington and liang 2000 purchasing power parity over two centuries journal of international money and finance 19 751 755 examine the long span of sterling dollar real exchange rate data of lothian and taylor 1996 real exchange rate behavior the recent float from the perspective of the past two centuries journal of political economy 104 488 509 and claim to reject long run purchasing power parity by fitting time trends or by considering very high order autoregresssive representations this reply demonstrates however that the central claims of lothian and taylor are in fact strengthened by the implications of cuddington and liang s analysis in that while the economic importance of introducing trend terms is slight this leads to a faster estimated speed of mean reversion c 2000 elsevier science ltd all rights reserved jel classification f31 f41 c22

a panel project on purchasing power parity mean reversion within and between countries abstract previous time series studies have shown evidence of mean reversion in real exchange rates deviations from purchasing power parity ppp appear to have half lives of approximately four years however the long samples required for statistical significance are unavailable for most currencies and are potentially inappropriate because of regime changes in this study we re examine deviations from ppp using a panel of 150 countries and 45 annual post wwii observations our panel shows strong evidence of mean reversion that is similar to that from long time series ppp deviations are eroded at a rate of approximately 15 annually i e their half life is around four years such findings can be masked in time series data but are relatively easy to find in cross sections

the role of royalties in resource extraction contracts the manner in which governments charge mineral resource producers has been the subject of considerable debate income based charges such as resource rent taxes have been advocated on the theory that royalties and other output based charges create inefficiency by distorting production decisions using a principal agent approach to resource contracts separating asset ownership from asset use we demonstrate that royalties can be efficient under conditions of certainty and also when there is uncertainty and asymmetric information royalties serve a key pricing purpose signaling the marginal impact of extraction on the residual value of reserves and surrounding land or sea

equilibrium product bundling this article offers an equilibrium theory of product bundling by rival firms in several models where a primary good is produced in a duopoly market and one or more other goods is produced under perfectly competitive conditions bundling is shown to emerge as an equilibrium strategy of one or both of the duopolists for its role as a product differentiation device when the rival firms can commit to bundling sales their profits are higher but social welfare is reduced copyright 1997 by university of chicago press

a graphical analysis of bundling by comparing the demand for a bundle and the vertical sum of the demands for its components this article analyzes the profitability and welfare consequences of bundling if it does not lower costs bundling tends to be profitable when reservation values are negatively correlated and high relative to costs if bundling lowers costs and costs are high relative to average reservation values positively correlated reservation values increase the incentive to bundle bundling and charging a price equal to the sum of the components prices lowers consumer surplus bundling can however increase consumer surplus when it results in lower prices copyright 1995 by university of chicago press

multiproduct monopoly commodity bundling and correlation of values through what selling strategy can a multiproduct monopolist maximize his profits when his knowledge about individual consumers preferences is limited one possibility extensively studied in the context of a single good monopoly is to use quantity dependent pricing as a means of discriminating among customers with differing tastes see for example oi 1971 and maskin and riley 1984 an alternative technique for price discrimination first suggested by stigler 1968 and analyzed further by adams and yellen 1976 is for the monopolist to package two or more products in bundles rather than selling them separately through a series of examples adams and yellen illustrate that bundling can serve as a useful price discrimination device even when all consumers willingnesses to pay for each of the goods individually are unaffected by whether they are also consuming the other product a typical example is illustrated in figure i adapted from figure iv in adams and yellen where there are two goods three consumers ab c who consume at most one unit of each good with reservation values for each good that are independent of whether the other good is consumed and zero costs of production there a bundle offered at a price of 100 fully extracts all potential surplus which would be impossible pricing the goods independently unfortunately though these authors do not provide any general characterization of the circumstances in which bundling is actually a multiproduct monopolist s optimal strategy their examples however such as figure i create the impression that the profitable use of bundling

searching for stationarity purchasing power parity under the current float abstract using panel data methods we investigate long run purchasing power parity by testing for unit roots in real exchange rates of industrial countries under the current float the evidence against the unit root hypothesis is stronger for larger than for smaller panels for monthly than for quarterly data and when the german mark rather than the united states dollar is used as the base currency while we find that accounting for serial correlation considerably weakens the evidence against the unit root null the results as a whole are consistent with long run purchasing power parity

resource taxation with heterogeneous quality and endogenous reserves abstract this paper analyzes the impact of mining taxation on the intertemporal extraction profile for a heterogeneous ore body the extraction profile specifies both quantities and qualities extracted in each period total extraction is thus endogenously determined the taxes explicitly considered are severance taxes ad valorem or per unit on metal or on ore property taxes and profits taxes with depletion allowance the intertemporal framework integrates economic and geological factors generating new results on extraction distortions and providing qualification or reconciliation of previous diverse results in this area

an empirical examination of long run purchasing power parity using cointegration techniques this paper presents an empirical analysis of long run purchasing power parity ppp for five major exchange rates using recently developed econometric techniques on the cointegration of economic time series our empirical results are extremely unfavourable to the ppp hypothesis as a long run equilibrium condition even with an allowance made for measurement error and or tranportation costs in particular we are unable to reject the hypothesis of non cointegration of the exchange rate and relative prices for any of the countries concerned far from finding a stable long run proportionality between exchange rates and relative prices our results therefore suggest that they tend to drift apart without bound

the overvaluation of purchasing power parity abstract recent panel studies of purchasing power parity have reported strong evidence of mean reversion in real exchange rates however these studies fail to control for cross sectional dependence in the data this failure has dramatic consequences raising the significance level of tests with a nominal size of 5 percent to as much as 50 percent it is shown in this paper that controlling for cross sectional dependence no evidence against the random walk null can be found in panels of up to 64 real exchange rates this finding cannot be attributed to low power as there is ample power in panels of this size to reject the unit root null