durable goods and product obsolescence the issue of product obsolescence is addressed by examining the optimal sales strategy of a monopolist firm that may introduce an improved version of its current product consumers expectations of a forthcoming product lowers the price that they are willing to pay for the current product because of its loss in value due to obsolescence the new product is characterized by consumers increased willingness to pay and by its competitive interaction with the old product these characteristics affect the tradeoff that the firm makes between the cost of waiting for new product sales versus the cost of cannibalizing these sales we analyze the effect of these characteristics of the new product on the firm s optimal sales strategy we consider the various policy measures available to the firm including limiting initial sales in order to lower cannibalization of the new product buying back the earlier version of the product in order to generate greater demand for the new product and announcements of future product introductions we find that for modest levels of product improvement the firm s optimal policy is to phase out sales of the old product while for large improvements a buy back policy is more profitable lastly we find that the firm is better off if it informs consumers whether a new product is forthcoming

does the gap in family friendly policies drive the family gap a segregation of the labour market into a family friendly and a non family friendly sector has the effect that women self select into the sectors depending on institutional constraints preferences for family friendly working conditions and expected wage differences we find that neglecting the sector dimension tends to understate the effect of birth related interruptions in both sectors the combined effect of a large depreciation effect and no recovery means that females in the non family friendly sector e g private sector are punished severely after childbirth in the family friendly sector e g public sector we find complete catch up

the effect of information streams on capital budgeting decisions in this paper a new decision rule for capital budgeting is considered a firm has the opportunity to invest in a project of uncertain profitability over time the firm receives additional information in the form of signals indicating the profitability of the project the belief that the firm needs to have in a profitable project for investment to be optimal is calculated and analyzed it is shown that the probability of investing in a project with low profitability is larger when the firm uses a conventional rule like the net present value rule as a counterintuitive result it is obtained that it can be optimal to undertake the investment at a later point in time in case the expected number of signals per time unit is higher also an error measure is discussed that indicates the accuracy of capital budgeting rules in this stochastic environment

is there a glass ceiling in sweden using 1998 data we show that the gender log wage gap in sweden increases throughout the wage distribution and accelerates in the upper tail we interpret this as a strong glass ceiling effect we use quantile regression decompositions to examine whether this pattern can be ascribed primarily to gender differences in labor market characteristics or in the rewards to those characteristics even after extensive controls for gender differences in age education both level and field sector industry and occupation we find that the glass ceiling effect we see in the raw data persists to a considerable extent

welfare aspects of technological adoption with learning abstract this paper considers the welfare implications of adoption of a new technology when this technology is characterized by costs of adaptation and some localized learning effects a two period model is developed to represent the adoption game between firms in a duopolistic framework optimal social patterns of adoption are compared with private patterns emerging as equilibria of the game it is shown that differences between the two patterns are due first to the shape of the demand function of the product sold on the duopolistic market and secondly to strategic interaction effects between the adopting firms

hitting the jackpot product proliferation by multiproduct firms under uncertainty this paper presents a model of product proliferation by multiproduct firms under uncertainty firms introduce new differentiated products because they want to hit as many jackpots as possible products with high profits and long lives there is uncertainty about the success of new products as the probability of hitting a jackpot increases product proliferation increases more products are introduced and expected in equilibrium the expected number of products in equilibrium is always less than at the optimum but in industries with multiple firms as the probability of hitting a jackpot increases rivalry intensifies and that gap shrinks

innovation and imitation in a duopoly in a duopoly where one firm has the idea for a non patentable innovation the expected profits from the innovation will not be a monotonic function of the cost of innovating furthermore a costly innovation may be undertaken where an inexpensive one would not have been all other things being equal

technological expectations and adoption of improved technology abstract attention is focused upon the adoption demand rather than the creation supply of new technology which improves from time to time based on the expected flow of technological progress over which the firm demander has no control it must decide either to adopt the current best available technology or to postpone adoption the distinguishing features of the model are that more than one technological innovation is anticipated and expectations about the likelihood of such innovations are revised as time passes since the last innovation our analysis shows that the firm will adopt the current best practice if its technological lag exceeds a certain threshold moreover as time passes without new technological advances it may become profitable to purchase a technology that has been available even though it was not profitable to do so in the past

sources procedures and microeconomic effects of innovation fabio arcangeli paul david frank engelman christopher freeman massimo moggi richard nelson luigi orsenigo nathan rosenberg michele salvati g n von tunzelman two anonymous referees and the participants at the meeting of the committee on distribution growth and technical progress of the italian national research council cnr rome november 16 1985 have helped with various redraftings a particularly grateful acknowledgment is for the insightful and patient help of moses abramovitz this work has been undertaken at the science policy research unit spru university of sussex as part of the research program of the designated research centre sponsored by the economic and social research council esrc earlier support to the research that led to this paper by the italian national research council cnr is also gratefully acknowledged the statistical research has been undertaken with the assistance of stephano brioschi ilaria fornari and giovannu prennushi

the reaper and the scanner indivisibility led incremental innovations and the adoption of new technologies widespread adoption of a new capital embodied technology requires a continu ous flow of incremental innovations a few of them address the key problem of indivisibility by making renting the new machine a viable alternative to buying it or by dividing it up into modular elements such incremental innovations differ from the learning by doing effects usually considered by diffusion models and greatly affect the structure of the adopting industry the case for keeping them in due account is made by revisiting paul david s classic paper on the mccormick reaper by criticising the subsequent evolution of threshold models of adoption and by summarising my own findings on the diffusion of electronic pre press devices

modeling multiattribute utility risk and belief dynamics for new consumer durable brand choice this paper proposes a brand choice model to aid in the prelaunch management of a new consumer durable entry in an existing category the model contributes to theory by integrating the critical phenomena of multiattribute preference risk and dynamics in an individual level expected utility framework the integration is based on established theoretical constructs in utility bayesian decision analysis and discrete choice theory measurement and estimation procedures are presented an application is described and the managerial relevance of this work as a planning and forecasting tool is examined

influence of social learning on exchange rate policy in developing countries a preliminary finding by using a suitable econometric model this study shows that beyond factors postulated by theorists social learning is a very powerful phenomenon for guiding developing countries in their exchange rate policy we introduce two variables that fairly encapsulate features of learning among neighbours the new variables together with those advanced in theory are then used to determine choice of a managed float by analysing 1993 cross section data from asian developing countries

motives to adopt renewable electricity technologies evidence from sweden the diffusion of renewable electricity technologies rets has to speed up for countries to reach their often ambitious targets for renewable energy generation this requires a large number of actors including individuals companies and other organizations to adopt rets policies will most likely be needed to induce adoption but there is limited knowledge about what motivates ret adoption the purpose of this paper is to complement and expand the available empirical evidence regarding motives to adopt rets through a survey to over 600 ret adopters in sweden the main finding of the study is that there are many different motives to adopt rets and that ret adopters are a heterogeneous group with regard to motives although environmental concerns interest in the technology access to an re resource and prospects to generate economic revenues are important motives in general adopters differ with regard to how large importance they attach to the same motive and each adopter can also have several different motives to adopt there are also differences in motives between adopter categories especially independent power producers vs individuals and diversified companies and between rets especially wind power vs solar power this implies that a variety of policy instruments might be needed to induce further adoption of a variety of rets by a variety of adopter categories

technology diffusion and public policy a useful typology of technological change is provided by the schumpeterian trilogy invention the generation of new ideas innovation the development of those ideas through to the first marketing or use of a technology and diffusion the spread of new technology across its potential market until recently policy schemes in most oecd countries have tended to focus predominantly on the invention and innovation or science and r d end of this technology spectrum see e g limpens et al i 992 although it is generally realised that it is the process of diffusion or use of technology that creates productive potential and competitiveness policy initiatives have largely bypassed opportunities to improve the diffusion process if this may seem misplaced emphasis it does in fact reflect the state of the academic literature which is wide ranging and extensive as it relates to policies on r d but small and fragmented as regards policies on diffusion currently a gradual reorientation of policy direction toward diffusion seems to be taking place the us and uk governments for example have recently proposed major technology policy initiatives that despite differences in emphasis both stress the importance of creating an infrastructure conducive to a rapid spread of awareness and knowledge of innovations we argue that although sensible in themselves such policies may be too limited in scope and that a broader policy stance may be needed this paper has two main objectives the first is to provide an overview of why policy intervention in the diffusion process may be desirable and what form it might take this discussion is rather long since to the best of our knowledge there is no published systematic synthesis of the diffusion policy literature though see stoneman i987 for an earlier attempt the second aim is to look at actual diffusion policies and their impacts to make the task manageable we are restricting this paper to a discussion of the diffusion of new process technologies although similar issues apply to new consumer technologies these are not explicitly addressed we also consider diffusion policy only within the context of a given institutional and macroeconomic environment although it may well be that the supply of skilled manpower the nature of the capital market animal spirits and entrepreneurship fiscal and monetary policies will all impact upon the diffusion path improvements in these areas will also impact upon a whole host of other aspects of the economy s performance to use a plea for diffusion policy as a rationale for changes in such areas would be equivalent to the tail wagging the dog and thus they fall outside the remit of this paper

the effects of expectations on technology adoption some empirical evidence n rosenberg 1976 argues that in many markets prospective buyers for an innovation are strongly influenced by expectations concerning the timing and significance of future improvements the primary objectives of this article are to provide a model of the innovation decision process of user firms that expect improvements in current best technology and to offer an empirical study that tests the model s predictions among other results the author finds empirical support for rosenberg s argument and demonstrates theoretically that compared to models without technological expectations and learning the optimal decision process is nonmonotonic copyright 1994 by blackwell publishing ltd

an evolutionary analysis of insurance markets with adverse selection abstract the equilibrium nonexistence problem in rothschild and stiglitz s insurance market is reexamined in a dynamic setting insurance firms are boundedly rational and offer menus of insurance contracts which are periodically revised profitable competitors contracts are imitated and loss making contracts are withdrawn occasionally a firm experiments by withdrawing or innovating a random set of contracts we show that rothschild and stiglitz s candidate competitive equilibrium contracts constitute the unique long run market outcome if innovation experiments are restricted to contracts which are sufficiently similar to those currently on the market

the demand for information and the diffusion of a new product abstract the paper examines the implications of the ability of a consumer to learn about the characteristics of a new product on the diffusion of the product over time the demand for information by the consumer is shown to generate a sigmoid diffusion curve for total sales of the product further it is shown that over time the elasticity of demand along the diffusion curve increases

discontinuous adoption paths with dynamic scale economies this paper examines the equilibrium adoption patch for two innovations when there are network externalities we show that the existence of significant increasing returns in system scale can give the result that one variant will drive out the other one and so emerges as the unique standard for the industry moreover if network externalities are sufficiently strong then the equilibrium adoption path is discontinuous that is it includes a catastrophe point

on the adoption of new technologies we investigate the incentives of private firms to adopt new technologies econometric investigation is performed on a pooled sample of individual us airline firms over the period 1971 to 1986 for which extensive information on available jet aircraft technology and fleet choice have been recorded given the incidence of successive commercial aircraft innovations and variation in production attributes across firms we are able to consider a wider array of time dependent and time independent adoption influences than in previous firm level studies to the extent that our study provides useful general insights into adoption decisions by firms the results have implications for us global competitiveness policy one key finding is that firms subject to increased product market competition exhibit a higher propensity to adopt technological innovations

information capacity and innovation adoption researchers of innovation adoption and diffusion often have tested the hypothesis that firms with greater capacities to gather and evaluate information should adopt sooner however the data generally do not support this hypothesis a theoretical model of innovation adoption under uncertainty is developed to show that greater information capacity implies not only faster learning which tends to reduce the expected delay until adoption but also a more stringent adoption criterion which tends to increase the expected delay the resulting ambiguity provides an explanation for the lack of empirical support for this hypothesis

strategic timing of adoption of new technologies under uncertainty abstract in this paper we introduce experience effects into a duopoly game of timing of adoption of new technologies which exhibit exogenous technological progress departing from the existing literature with this model we obtain continuous and downward sloping reaction functions we find that a higher level of uncertainty increases the extent of dispersion between the equilibrium timings of adoption furthermore we find that the equilibrium timings are even more dispersed when the leader takes the follower s reaction into account when firm roles are made endogenous we find that if there is an incentive to lead follow the equilibrium timings are more less dispersed finally we show that it is possible for collusive adoption to improve welfare

uncertainty competition and the adoption of new technology faced with the decision of whether or not to adopt a new technology whose economic value cannot be gauged with certainty the manager of the firm may elect to decrease the uncertainty by sequentially gathering information at a unit cost of c 0 updating his prior beliefs in a bayesian manner uncertainty regarding the actions of a competitor however cannot be reduced our model allows a manager to account for potential competition either substitute or complementary by inclusion of strategic considerations modelled in a game theoretic setting we show that the firm s best response mapping satisfies a dynamic programming recursion even when the one period reward function is unbounded providing management with a familiar tool to solve its problem best response behavior is characterized by a monotone sequence of pairs of threshold numbers which give rise to a cone shaped continuation region the continuation region is shown to shift up down with increases in the expected level of substitute complementary competition making the firm less more likely to adopt the innovation finally the existence of a nash equilibrium in cone shaped strategies is established

strategic intrafirm innovation adoption and diffusion 1 introduction this paper addresses two empirical observations that are common in the extensive literature on innovation diffusion first a firm usually adopts an innovation over time not instantaneously that is there are intrafirm diffusions mansfield 1968 nasbeth and ray 1974 romeo 1975 stoneman 1981 1983 second the time path of an intrafirm diffusion has a predictable shape diffusion curves plot the extent of adoption against time and are generally s shaped that is they are initially convex reach an inflection point and then are concave thereafter often they are also skewed in that they are initially convex for less than half of the length of the diffusion this skewing can be so severe that the diffusion curve is essentially concave davies 1979 stoneman 1983 given the voluminous literature on innovation diffusion it is surprising that intrafirm diffusions have not received more attention with few exceptions noted below the theoretical literature assumes adoption is a discrete choice variable and so occurs instantaneously moreover empirical studies typically assume adoption occurs at the date of first use of the innovation by the firm to the extent intrafirm diffusions occur these studies clearly overestimate the speed at which the innovation is put into use and thus the speed at which its benefits accrue to the firm and society intrafirm diffusions are especially common in the case of capital embodied new process innovations because adoption involves adjustment costs as well as acquisition costs in a seminal study mansfield 1968 found that the time interval between 10 and 90 usage of diesel locomotives ranged from three to more than 14 years for firms in the u s railroad industry more recent examples abound most readers have undoubtedly experienced at least once the adoption of new computer equipment in their workplace from my own experience not all users are upgraded to the new equipment within a day a week or even a month hence in this paper i analyze the intrafirm diffusion of a new process innovation in a differential game model of an oligopoly the model s predictions are consistent with the empirical regularities noted above first an intrafirm diffusion occurs in equilibrium because the marginal cost of adoption is increasing in the rate of adoption it is not optimal to adopt instantaneously just as it is not optimal to adjust to the desired level of a stock instantaneously when adjustment costs are increasing at the margin second the equilibrium intrafirm diffusion curve is either s shaped or concave moreover this diffusion curve is more likely to be sshaped the more competitive the industry the larger the marginal cost of adoption or the preinnovation unit cost of production or the smaller the demand the analysis also shows a firm s diffusion is longer and so the extent of its adoption at any date is lower the more competitive the industry the larger the marginal cost of adoption or the pre innovation unit cost of production or the smaller the demand that is a diffusion is longer the smaller the incentive to adopt whether due to lower flow profit or higher adoption flow cost one surprising result is that an increase in the unit cost reduction from the innovation has an ambiguous effect on the intrafirm diffusion the reason is that there are two conflicting effects first as is obvious a larger cost reduction allows each firm to earn a larger flow profit at every date from the same rate of adoption however a more subtle effect is that it also allows the firm to earn the same flow of profit with a slower rate of adoption and so lower adoption costs that is the firms also have an incentive to spread out the diffusion over a longer period of time to save on adoption costs these results are important for two reasons first they show that diffusion curves are more likely to have an s shape for longer diffusions

money for nothing universal child care and maternal employment abstract the strong correlation between child care and maternal employment rates has led previous research to conclude that affordable and readily available child care is a driving force both of cross country differences in maternal employment and of its rapid growth over the last decades we analyze a staged expansion of subsidized child care in norway our precise and robust difference in differences estimates reveal that there is little if any causal effect of subsidized child care on maternal employment despite a strong correlation instead of increasing mothers labor supply the new subsidized child care mostly crowds out informal child care arrangements suggesting a significant net cost of the child care subsidies

adoption and diffusion of an innovation of uncertain profitability the argument has frequently been made that the pattern of diffusion associated with most new innovations will typically have certain characteristics a diffusion curve for an innovation is usually defined as the proportion of its potential users who have already adopted as a function of time measured from the first adoption many empirical studies by both economists and other social scientists have shown that diffusion curves nearly always have two distinct characteristics i they are s shaped the proportion adopted is an increasing function of time which is initially convex but eventually becomes concave and ii they tend to be right hand skewed the inflection point occurs at a time corresponding to a proportion adopted which is less than one half so that the function is concave over the greatest amount of time in fact this skewing is occasionally severe enough to make the diffusion curve appear concave everywhere the focus of most empirical studies of innovation diffusion has centered on identification of either the major determinants of the speed of diffusion or the characteristics of firms which determine how long they delay adoption the seminal contributions are griliches 6 study of hybrid corn and mansfield s 121 study of 12 industrial innovations these studies and most of the similar ones following conclude that diffusion is faster for innovations with higher profitability and that large firms tend to be the earliest adopters some studies e g mansfield 121 herregat 71 have attempted to ascertain

from mill town to board room the rise of women s paid labor the widespread participation of women in paid labor outside of the home and in the highest echelons of society would have been unheard of a century ago this paper documents this dramatic change in women s social and economic status and argues that it was determined both by contemporaneous demand factors and by the characteristics expectations and social norms regarding work and family of different cohorts of women history suggests that change in women s labor force experiences may be slow because it must await the entry of new cohorts of women and also of men into the labor market

the effect of piracy on the market penetration of subscription software software piracy is not necessarily harmful to a software firm seeking to launch a new product when strategically managed through the use of price and protection measures piracy establishes the initial adopters of the software who in turn influence other users to buy the product we examine the role of piracy in affecting the adoption of subscription software products we present an individual level model in an adaptive population setting intended to determine the price protection mix that maximizes the discounted profit stream over the life of the software an extension for nonsubscription software is also discussed

risk aversion information acquisition and technology adoption we use a dynamic programming model to study the impacts of risk aversion on information acquisition in technology adoption decisions in this model the benefit of the technology is uncertain and in each period the decision maker dm may adopt the technology reject the technology or pay to acquire a signal about the benefit of the technology the dynamic programming state variables are the dm s wealth and a probability distribution that describes the dm s beliefs about the benefit of the technology these distributions are updated over time using bayes rule if the signal generating process satisfies the monotone likelihood ratio property and the dm is risk neutral the value functions and policies satisfy natural monotonicity properties a likelihood ratio improvement in the distribution on benefits leads to an increase in the value function and moves the dm away from rejection and toward adoption with risk aversion the value functions now representing expected utilities will be monotonic but

imitators and optimizers in cournot oligopoly we analyze a symmetric n firm cournot oligopoly with a heterogeneous popu lation of optimizers and imitators imitators mimic the output decision of the most successful firms of the previous round a la vega redondo 1997 optimizers play a myopic best response to the opponents previous output firms are allowed to make mistakes and deviate from the decision rules with a small probability apply ing stochastic stability analysis we find that the long run distribution converges to a recurrent set of states in which imitators are better o than are optimizers this finding appears to be robust even when optimizers are more sophisticated it suggests that imitators drive optimizers out of the market contradicting a funda mental conjecture by friedman 1953

innovation adoption and diffusion when there are competing innovations abstract firms face a choice between two innovations without knowing which of the two is better each firm has a prior that one of the innovations is better which is updated by bayes rule as trials with the innovations are made a simple decision rule indicating which innovation should be tried given any posterior is derived and used to define an expected diffusion curve for the better innovation this curve has the commonly observed ogive shape even in the absence of any external demonstration effect when the distribution of firm priors belongs to a general class

rules of thumb for social learning this paper studies agents who consider the experiences of their neighbors in deciding which of two technologies to use we analyze two learning environments one in which the same technology is optimal for all players and another in which each technology is better for some of them in both environments players use exogenously specified rules of thumb that ignore historical data but may incorporate a tendency to use the more popular technology in some cases these naive rules can lead to fairly efficient decisions in the long run but adjustment can be slow when a superior technology is first introduced

word of mouth communication and social learning this paper studies the way that word of mouth communication aggregates the information of individual agents we find that the structure of the communication process determines whether all agents end up making identical choices with less communication making this conformity more likely despite the players naive decision rules and the stochastic decision environment word of mouth communication may lead all players to adopt the action that is on average superior these socially efficient outcomes tend to occur when each agent samples only a few others i introduction economic agents must often make decisions without knowing the costs and benefits of the possible choices given the frequency with which such situations arise it is understandable that agents often choose not to perform studies or experiments but instead rely on whatever information they have obtained via casual word of mouth communication reliance on this sort of easily obtained information appears to be common in circumstances ranging from consumers choosing restaurants or auto mechanics to business managers evaluating alternative organizational structures this paper studies two related environments in arguing that individuals reliance on word of mouth communication has interesting implications for their aggregate behavior first motivated by the diffusion of new technologies we consider a choice between two competing products with unequal qualities or payoffs and show that the structure of communication is important in determining whether the population as a whole is likely to learn to use the superior product second we consider a choice between two products or practices that are equally good and ask whether consumers are likely to herd onto a single choice or whether diversity will obtain even in the long run we explore the implications of word of mouth communication in a simple nonstrategic environment there is a large population of identical players each of whom repeatedly chooses between two possible actions each player s payoff is determined by his own

better reply dynamics and global convergence to nash equilibrium in aggregative games we consider n person games with quasi concave payoffs that depend on a player s own action and the sum of all players actions we show that a discrete time stochastic process in which players move towards better replies the better reply dynamics converges globally to a nash equilibrium if actions are either strategic substitutes or strategic complements for all players around each nash equilibrium that is asymptotically stable under a deterministic adjusted best reply dynamics we present an example of a 2 person game with a unique equilibrium where the derivatives of the best reply functions have different signs and the better reply dynamics does not converge

three problems in learning mixed strategy nash equilibria this paper discusses three problems that can prevent the convergence of learning mechanisms to mixed strategy nash equilibria first while players expectations may converge to a mixed equilibrium the strategies played typically fail to converge second even in 2 2 games fictitious play can produce a sequence of frequency distributions in which the marginal frequencies converge to equilibrium mixed strategies but the joint frequencies violate independence third in a three player matching pennies game with a unique equilibrium it is shown that if players learn as bayesian statisticians then the equilibrium is locally unstable journal of economic literature classification numbers c72 c73 d83

co evolution of firms and consumers and the implications for market dominance consider a setting in which rms randomly discover new ideas that a ect their products or services and implement favorable ones at the same time that rms are adapting their o erings consumers are searching among rms for the best match it is shown that implicit in these dual dynamics is an increasing returns mechanism which can result in one rm dominating the market in the long run the conditions under which there is sustained market dominance are characterized

invest or exit optimal decisions in the face of a declining profit stream even in the face of deteriorating and highly volatile demand firms often invest in rather than discard aging technologies to study this phenomenon we model the firm s profit stream as a brownian motion with negative drift at each point in time the firm can continue operations or it can stop and exit the project in addition there is a one time option to make an investment that boosts the project s profit rate using stochastic analysis we show that the optimal policy always exists and that it is characterized by three thresholds there are investment and exit thresholds before investment and there is a threshold for exit after investment we also effect a comparative statics analysis of the thresholds with respect to the drift and the volatility of the brownian motion when the profit boost upon investment is sufficiently large we find a novel result the investment threshold decreases in volatility

the role of technological expectations in a mixed model of international diffusion of process innovations the case of open end spinning rotors abstract in the years following the introduction of open end rotors a major innovation in cotton spinning technological change in spinning has been characterized by fast rates of introduction of incremental innovations this has made possible considerable improvements in the quality of products as well as reductions in the cost of spinning this case seems especially appropriate for analysing the effects of incremental innovations on the rate of diffusion one the one hand expectations of continuing incremental change may have actually slowed the diffusion of open end rotors contrarily increased profitability from their adoption may have reinforced the rate of diffusion a mixed model of diffusion one that is able to evaluate the role of supply forces such as the introduction of incremental innovations and at the same time the role of bounded rationality and learning by imitating has been developed it draws on the behavioural literature and upon the epidemic approach due to mansfield results of an econometric test on international data available for 26 countries confirm that the rate of introduction of incremental innovations has reduced the rate of diffusion this is especially the case in countries where the technological change in spinning was originated and consequently technological expectations were higher

human capital information and the early adoption of new technology when producers are uncertain or have imperfect information about the profitability of adopting new technology their adoption behavior depends on the endowment of human capital and the investment in adoption information this study analyzes the role of education experience and information acquisition in the decision to be an early adopter the findings support the hypothesis that adoption decision making is a human capital intensive activity the econometric evidence presented suggests that education and information reduce adoption costs and uncertainty and thereby raise the probability of early adoption adoption behavior is also shown to vary significantly across firm size

boom and bust patterns in the adoption of financial innovations we develop a dynamic model of the adoption of financial innovations each period firms decide whether or not to adopt an innovation of uncertain value and the profitability of each period s adoptions reveals information about the innovation s value we show that characteristics of financial innovation waves cited by critics as evidence of irrational excess are in fact consistent with fully rational behavior we also show that social welfare is enhanced when more firms adopt innovations of questionable value and that financial intermediaries base an incentive to encourage such adoption article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

information and profitability estimates modelling the firm s decision to adopt a new technology this paper uses a response surface based on catastrophe theory to examine the interaction of information and profitability estimates on the firm s adoption of a new technology or innovation as such the paper builds on the conceptual ideas behind mccardle s 1985 work an illustrative example using simulated data is presented to indicate how one might operationalize the key constructs for the purpose of estimating the model

reputations in the adoption of a new technology abstract this paper studies the effects of uncertainty on the timing of adoption of a new technology in a duopoly firms are uncertain of the innovative capabilities of their rivals and about the profitability of adoption these features lead to a richer and in some respects more plausible theory of adoption in which rents from delayed adoption are always realized and returns are not equalized across adoption times

vocational training and gender wages and occupational mobility among young workers this paper investigates the relationship between the gender wage gap the choice of training occupation and occupational mobility we use longitudinal data for young workers with apprenticeship training in west germany workers make occupational career choices early during their careers and women and men pursue very different occupational careers we reconsider whether through occupational segregation women are locked in low wage careers kunze 2005 or whether they can move up to higher wage paths through mobility we furthermore investigate whether patterns have changed across cohorts during the period 1975 and 2001 and whether effects vary across the distribution the main results are first while there exists a persistent gender wage gap over experience the gap has decreased over time second in the lower part of the wage distribution the gap is highest and it increases with experience third occupational mobility is lower for women than for men and the wage gains due to occupational mobility are higher for men than for women especially in the lower part of the wage distribution we conclude that occupational mobility has reduced the gender wage gap but lock in effects are still stronger for women compared to men

appropriability and commercialization evidence from mit inventions the effects of appropriability on invention have been well studied but there has been little analysis of the effect of appropriability on the commercialization of existing inventions exploiting a database of 805 attempts by private firms to commercialize inventions licensed from the massachusetts institute of technology mit between 1980 and 1996 we explore the influence of several appropriability mechanisms on the commercialization and termination of projects to develop products based on university inventions our central hypothesis is that the relationship between a licensee s decision to either terminate or commercialize the invention is driven by the current market value of the invention as well as the option value of delaying its commercialization we use a competing risks framework that allows for nonparametric heterogeneity and correlated risks we find that better appropriability in the sense of more effective patent strength and secrecy has a strong negative effect on the hazard of license termination the effectiveness of learning has a strong positive effect on the hazard of technology commercialization while lead time has a negative effect

uncertain search a model of search among technologies of uncertain values in the standard search problem there is an infinite pool of items whose distribution of values is known a decision maker draws an item from the pool observes its value and decides whether to keep it or to draw another item he can keep only one item and he seeks the item with the largest value in the standard uncertainty resolution problem there is only one item and the value of that item remains uncertain even after it is drawn the decision maker sequentially collects observations on the value of the item and decides whether to keep the item discard the item or take another observation uncertain search marries the sequential drawing from a pool of items from the search literature with the unknown value of a drawn item from the uncertainty resolution literature presented in the context of technology adoption it considers drawing from a pool of new technologies whose values remain unknown even after being drawn the decision maker sequentially purchases information in order to bayesianly update

adoption of competing inventions by united states steel producers a hstract this research investigates innovative behavior in the u s steel industry under the assumption that basic oxygen and large electric furnaces are competing technologies the empirical model of innovation is based on recent theoretical research the coefficients are estimated by a seemingly unrelated tobit approach the research finds innovation is strongly influenced by a demonstration effect adoption is also influenced by potential cost savings and technical progress there is no evidence that large u s steel producers modernized more slowly than their smaller rivals the large electric furnace becomes sufficiently attractive by 1980 that firms choose not to adopt basic oxygen

innovation firm size and growth in a centralized organization the optimal innovation firm size and growth are derived for a centrally controlled firm in which only the entrepreneur evaluates and restores current projects or evaluates and adopts new projects current projects are subject to failure due to entry and possible obsolescence while new projects may not be successful the optimal allocation of attention implies bounds on firm size and that the rate of innovation depends not only on monopoly profits firm size and technological opportunity but also on the probability of obsolescence the effects of monopoly power and firm size on innovation also depend on the degree of obsolescence

technology adoption with uncertain future costs and quality in this paper we study the impact of uncertainty about future innovations in quality and costs on consumers technology adoption decisions we model the uncertainty in the technology s quality and costs as a markov process and consider three models of the adoption decision the first model assumes that consumers do a simple net present value npv analysis that compares the npv of adopting to that of not adopting without considering the possibility of waiting the second model is a stochastic dynamic program that considers the possibility of waiting and views the adoption decision as a one time event i e the consumer will only make a single purchase the only question is when the third model allows repeat purchases so the consumer may upgrade by purchasing new versions of the technology whenever it suits her we study structural properties of these models e g the following what changes in qualities and costs will make the consumer better off what changes will encourage adoption we will see that the simple npv and single purchase model have many intuitive properties with the right notion of improvements and reasonable assumptions about the technology changes we find that improvements in the technology make the consumer better off and encourage adoption here improvements are defined using a partial order on quality and cost pairs the results are more complicated in the repeat purchase model under the same conditions on technology changes technology improvements will make the consumer better off however except for special cases of transitions these improvements may make the consumer better off and discourage adoption

economists models of learning abstract economic theorists have intensively studied learning in games and decisions over the last decade this essay puts some of the work in perspective and offers opinions about what still needs to be learned journal of economic literature classification numbers c73 d83

bayesian learning in an infant industry model abstract most analyses of the infant industry argument assume that production early on benefits subsequent production in deterministic fashion this paper presents an alternative framework for evaluating the infant industry argument that focuses on imperfect information as a barrier to entry initial entrants provide information of social value by reducing uncertainty for potential followers about the suitability of local conditions in contrast to earlier work i show that factors that increase the informational barrier to entry may lower the optimal subsidy to the infant industry and that the standard test of the success of infant industry policy is not always valid 1997 elsevier science b v

something to talk about social spillovers in movie consumption we exploit the randomness of weather and the relationship between weather and moviegoing to quantify social spillovers in movie consumption instrumenting for early viewership with plausibly exogenous weather shocks captured in lasso chosen instruments we find that shocks to opening weekend viewership are doubled over the following five weekends our estimated momentum arises almost exclusively at the local level and we find no evidence that it varies with either ex post movie quality or the precision of ex ante information about movie quality suggesting that the observed momentum is driven in part by a preference for shared experience and not only by social learning

learning preemption and the degree of rivalry we examine a model in which all firms receive common signals as to the uncertain profitability of an investment whose actual payoffs are split only among those who develop the project earliest the benefit from preempting rivals yields an equilibrium reduction in the amount of learning and earlier development as the number or rivals increases the set of equilibria shrinks as the number of rivals gets large and in the limit only the competitive outcome occurs

the rise of female professionals are women responding to skill demand for years college educated women were limited mainly to lower paying female dominated professions such as teaching and nursing over the past several decades however there has been a remarkable increase in the percentage of college educated women in higher paying traditionally male professional occupations in 1967 the fraction of college educated women working in these occupations was less than 20 percent by 1997 this number had increased to almost 40 percent this increase is particularly striking when compared to the slightly declining trend among college educated men what can explain this increase in female professionals there are a number of possible explanations one explanation is a demand shift favoring women over men in these highly skilled occupations while the notion of a gender specific demand shift is compelling in the case of high school graduate men and women who work in very different industries and occupations the story is much less convincing for the college educated group collegeeducated men and women work in more similar occupations and are presumably closer substitutes for each other to the extent that they are different the available evidence suggests that this may have worked to the disadvantage of women see francine blau and lawrence kahn 1997 another explanation and the one we focus on in this paper is that college educated women have responded to the rise in overall skill demand a phenomenon which has characterized the u s labor market during the 1980 s and perhaps even as early as the 1970 s an important margin of response for these women may have been labor market participation in 1970 less than 60 percent of college educated women were working the economy wide rise in skill demand may have attracted educated women not only from other occupations but from nonparticipation as well since virtually all college educated men work labor market participation is less likely to be a factor for men while we postulate that the overall increase in skill demand played an important role we are also aware that this is not the only explanation within these high wage professional occupations women s wages rose relative to male wages even as women increased their share this suggests to us that declining discrimination which both made it easier for women to enter these occupations and resulted in wage convergence vis a vis the male workers or unobserved skill upgrading also may have played a role in addition the spread of more effective birthcontrol devices roe v wade and no fault divorce laws just to name a few of the factors which changed marriage and fertility patterns of women also most likely contributed to women s willingness and ability to invest in career jobs see claudia goldin and lawrence katz 2000

experimentation imitation and stochastic stability abstract do boundedly rational agents repeatedly playing a symmetric game with a unique symmetric equilibrium learn over time to play it in this paper we model the dynamic interaction of two types of such agents experimenters and imitators whose behavior is characterized by simple rules of thumb we find that the stochastic process describing their play isstable in the large it converges globally and with probability one to a compact neighborhood of the equilibrium however its local behavior near the equilibrium depends in interesting ways on the details of the model journal of economic literatureclassification number d83

dominant firms and their alleged decline abstract by way of a survey of recent literature on the theory of strategic competition this paper focuses on the question of whether dominant firms decline the traditional argument suggesting decline is found to be based on a rather unsatisfactory modelling of dominance and more acceptable conceptualizations suggest that such privileged positions will persist

information acquisition and the adoption of new technology the profitability of a new technology is rarely known with certainty at its announcement date consequently prior to making an adoption decision it behooves the firm considering the adoption of this innovation to reduce the level of uncertainty associated with its profitability the firm accomplishes this by sequentially gathering information updating its prior estimate of profitability in a bayesian manner quantifying the uncertainty regarding the innovation permits application of dynamic programming techniques criteria are derived which tell the firm when to stop collecting information and make the adoption decision it will be shown that it is optimal for the firm to continue to collect information until its estimate of profitability crosses one of two thresholds upon crossing the upper threshold the firm adopts the technology whereas the firm rejects the technology if the lower threshold is crossed the model predicts that even the manager who behaves optimally will occasionally adopt unprofitable technologies and reject profitable ones

time to cook expenditure at retirement in spain detailed panel expenditure data from spain reveal little evidence of a retirement consumption puzzle in 1985 2004 there is a drop in food at home expenditure in the later years of the sample along with evidence of households paying lower prices for the food they purchase after retirement however our findings are consistent with a model that allows for home production as long as one accounts for the greater participation in housework by men after retirement coinciding with this latter period our work adds to the evidence from several countries and helps in reconciling the retirement consumption puzzle with life cycle models

stochastic adaptation in finite games played by heterogeneous populations we analyze stochastic adaptation in finite n player games played by heterogeneous populations containing best repliers better repliers and imitators individuals select strategies by applying a

the diffusion of new technology and the market for an innovation this article shows that the diffusion of a capital embodied process innovation results from a pattern of decreasing incremental benefits and adoption costs for later adoptions strategic behavior is inessential to this finding we develop a method for comparing diffusion rates for different market structures in the capital equipment market we consider cases with market power on the seller s side of the market and on the buyers side of the market a case with no market power and the welfare optimal case we find that a joint venture adopts an innovation more slowly than other market regimes to protect existing capital investments and that the adoption rate is slower than is socially optimal a monopoly supplier on the other hand adopts at a rate faster than is socially optimal this result is usually also the case when there is no market power finally we show that the monopoly supplier accelerates adoptions faster than in the case where there is no market power but retards later adoptions market power thus makes a difference in diffusion rates and on which side of the market that power lies makes a considerable difference

second mover advantages in the strategic adoption of new technology under uncertainty abstract this paper introduces technological uncertainty into a timing game of new technology adoption it is shown that the timing neither necessarily involves first mover advantages in precommitment equilibria reinganum review of economic studies xlviii 1981 395 405 nor rent equalization due to the threat of preemption fudenberg and tirole review of economic studies lii 1985 383 401 rather there may be second mover advantages because of informational spillovers furthermore the model predicts that the equilibrium payoffs will typically be discontinuous and non monotonic in the probability that the new technology is profitable a welfare analysis reveals several market failures and suggests that policy intervention should adequately depend on the nature of uncertainty and the rate of technological progress

technology choice and timing with positive network effects abstract when two competing and incompatible products coexist in a market potential users face a choice between the two products and the alternative of deferring the decision this paper examines the choice between the two substitutes where each one is subject to a positive network effect that is a user of one of the products experiences an increase in the value for each additional person using the same product we examine this buy or wait problem either for an individual or a manager making the investment on behalf of a firm by formulating and analyzing a decision theoretic model to model the stochastic evolution of market share we build on the generalized polya urn of arthur et al arthur w b ermoliev y m kaniovski y m 1987 path dependent processes and the emergence of macro structure european journal of operational research 30 3 294 303 allowing for composition of the market to affect not just the relative market shares but also the absolute growth rate of the market we show that the optimal strategy is defined by a pair of market penetration thresholds that depend on the market composition looking at the effect of the network effects on the optimal strategy we find that more pronounced network effects can either raise or lower the penetration thresholds

optimal timing of technology adoption abstract in a dynamic programming framework this paper investigates the optimal timing of technology adoption by a competitive firm when technology choice is irreversible and the firm faces a stochastic innovation process with uncertainties about both the speed of the arrival and the degree of improvement of new technologies a numerical example illustrates how the optimal timing decision is affected by changes in parameter values reflecting market conditions the firm s initial technological attributes and the characteristics of the stochastic innovation process some of these effects turn out to be in sharp contrast to common intuition contrasting the optimal decision rule derived here with the rule obtained under the net present value shows that the former implies a slower pace of adoption than implied by the latter the optimal decision rule is generalized for the case of multiple technology switches and it is shown that for all the switching decisions except the last one the optimal rule satisfies the net present value criterion

models of technology diffusion abstract the literature on new technology diffusion is vast and it spills over many conventional disciplinary boundaries this paper surveys the literature by focusing on alternative explanations of the dominant stylized fact that the usage of new technologies over time typically follows an s curve the most commonly found model which is used to account for this model is the so called epidemic model which builds on the premise that what limits the speed of usage is the lack of information available about the new technology how to use it and what it does the leading alternate model is often called the probit model which follows from the premise that different firms with different goals and abilities are likely to want to adopt the new technology at different times in this model diffusion occurs as firms of different types gradually adopt it there are actually many ways to generate an s curve and the third class of models which we examine are models of density dependence popularized by population ecologists in these models the twin forces of legitimation and competition help to establish new technologies and then ultimately limit their take up finally we look at models in which the initial choice between different variants of the new technology affect the subsequent diffusion speed of the chosen technology such models often rely on information cascades which drive herd like adoption behaviour when a particular variant is finally selected

on the diffusion of new technology a game theoretic approach this paper is an attempt at a rigorous albeit not exceedingly general analysis of the diffusion of new technology in particular consider an industry composed of two firms each using the current best practice technology the firms are assumed to be operating at nash equilibrium output levels generating a market price given demand and profit allocations when a cost reducing innovation is announced each firm must determine when if ever to adopt it based in part upon the discounted cost of implementing the new technology and in part upon the behavior of the rival firm if either firm adopts before the other it can expect to make substantial profits at the expense of the other firm on the other hand the discounted sum of purchase price and adjustment costs may decline with the lengthening of the adjustment period as various quasi fixed factors become more easily variable therefore although waiting costs the firm more in terms of foregone profits it may save money on the cost of purchasing the new technology thus the firm must weigh the costs and benefits of delaying adoption as well as take account of its rival s strategic behavior

dynamic patent licensing abstract this paper shows one way a fixed fee can dominate an auction if no one knows whether the innovation will succeed or not when it appears and if its life exceeds the life of the patent then selling one licence by fixed fee maximizes inventor profit for some probabilities of success the reason is a nonlicensee is better off when a rival buys a license because this reveals the nature of the innovation if it succeeds the nonlicensee can adopt in the future after the patent has expired this expected future gain can outweigh the expected loss during the life of the patent

impact of bayesian learning and externalities on strategic investment we investigate the interplay between learning effects and externalities in the problem of competitive investments with uncertain returns we examine a game theoretic duopoly investment model in which i a firm can learn about the profitability of the investment by observing the performance of the first mover and ii externalities exist between the investments of two firms we find a region of a war of attrition between the two firms in which the interplay between externalities and learning gives rise to counterintuitive effects on investment strategies and payoffs in particular we find that contrary to the conventional war of attrition where an increase in benefits for the follower generally delays the first move an increase in the rate of learning which tends to benefit the follower can hasten the first investment this paper was accepted by james smith decision analysis

endogenous fluctuations under evolutionary pressure in cournot competition abstract an evolutionary game theoretic model of cournot competition is investigated individuals choose from a finite set of different behavioral rules each rule specifies the quantity to be produced in the current period as a function of past quantities using more sophisticated rules may require extra information costs based upon realized payoffs the fractions of the population choosing a certain behavioral rule are updated according to the replicator equation with noise the long run behavior of the evolutionary system consisting of the population dynamics coupled with the quantity dynamics of the cournot game may be complicated and endogenous fluctuations may arise we consider a typical example where firms can choose between two rules the nash rule and the best reply rule we show that a homoclinic tangency between the stable and unstable manifold of the equilibrium occurs as evolutionary pressure increases implying bifurcation routes to complicated dynamics and strange attractors

imitators and optimizers in a changing environment abstract we analyze the repeated interaction between an imitating and a myopically optimizing player in an otherwise symmetric environment of changing marginal payoff focusing on finite irreducible environments and the case of strategic substitutes we unfold a trade off between the degree of interaction and the size of environmental shocks the optimizer outperforms the imitator if interaction is weak or shocks are large as to the case of duopoly this translates into small cross price elasticities or large shocks in marginal cost and or the maximum willingness to pay in these cases a changing environment creates selection pressure against imitative behavior

modelling cognitively bounded rationality an evaluative taxonomy abstract since its origins in the 1950s the notion of bounded rationality has been incorporated into economic theory using an array of methodological approaches this paper presents a taxonomy by which these approaches can be categorized and understood evaluating each approach against a range of important criteria at a time when the foundations of economic theory are being re examined this paper should be viewed as a first step towards an assessment of the appropriate role that this more realistic view of cognition should take in different areas of economic theory and also of the desirable characteristics of models that incorporate it

information revelation and strategic delay in a model of investment we model investment as an n player game with a pure informational externality each player s payoff depends only on his own action and the state of nature however because a player s action reveals his private information players wait to see what other players will do equilibrium is inefficient because delay is costly and information is imperfectly revealed we characterize the unique symmetric perfect bayesian equilibrium and study the robustness of delay which turns out to be sensitive to the reaction speed and the number of players we establish the following results i when the period length is very short the game ends very quickly and there is a form of herding or informational cascade which results in a collapse of investment ii as the period length increases the possibility of herding disappears iii as the number of players increases the rate of investment and the information flow are eventually independent of the number of players adding more players simply increases the number who delay iv in the limit the time profile of investment is extreme a period of low investment followed either by an investment surge or a collapse

endogenous diffusion of technology abstract this paper presents a positive theory of diffusion of technology it examines a two period model strategic firms are confronted by a process technology with an uncertain reduction in marginal costs the uncertainty is automatically resolved between the two periods adoption in the first period yields a leadership advantage relative to firms that do not adopt while simultaneous adoption by firms results in a cournot equilibrium the firms strategies are both production quantities and adoption timings these decisions are made at the same time thus firms face a trade off between early adoption and possibly reaping first mover advantages on one hand and deferring the adoption decision until after all the uncertainty is resolved but face the possibiity of being a follower in the market interestingly an endogenously determined diffusion rate is obtained as a pure strategy nash equilibrium of this game this means that while adoption and diffusion of technology results with probability one diffusion of a bad innovation is also possible it is also shown that in a market with one large firm and a nonatomic continuum of small firms there is a unique nash equilibrium in which the large firm adopts first and is a stackelberg leader and all the small firms decide whether or not to adopt after the uncertainty is resolved the implication of this result is simply that the diffusion of technology is to some extent determined by the relative size of firms in the industry

multiplant firms and innovation adoption and diffusion 1 introductionone empirical regularity associated with the adoption of new technology is that large firms tend to adopt sooner than small firms e g see davies 1979 mansfield 1968 mansfield et al 1982 stoneman 1983 1995 or hoppe 2002 the usual explanation of course is that large firms expect a greater return from adoption than small firms however large firms do not always adopt first as can be seen from the diffusion of several new processes in the u s steel industry the basic oxygen furnace and continuous casting adams and mueller 1982 and thin slab casting ghemawat 1993 1995 this article develops a new theoretical model of innovation adoption and diffusion that explains why large firms tend to adopt first but admits conditions under which small firms adopt first the analysis focuses on the adoption of an innovation of uncertain profitability when a firm s size is measured by the number of plants it operates as is well known one reason for operating multiple plants is production costs that are increasing at the margin another reason is the existence of economies of multiplant operations cost savings that result solely from the operation of multiple plants theoretical and empirical support for these economies is mixed theoretically the operation of multiple plants can allow savings in nonproduction costs such as transportation distribution and inventory it can also allow economies of massed reserves cost savings associated with retaining proportionately fewer spare parts backup machines and repair persons in reserve information sharing between plants can reduce production and adoption costs however multiplant operation can also result in greater information costs van zandt and radner 2001 show that because information processing takes time computational constraints limit the amount of information that can be used in reaching a decision this informational crowding out effect can result in decreasing returns to size or diseconomies of multiplant operation in a seminal wide ranging study scherer et al 1975 find little empirical evidence in support of multiplant economies moreover when these economies do exist they involve savings in nonproduction costs more recently in their comparative study of the performance of light water nuclear reactor power plants in the united states and france lester and mccabe 1993 do find empirical support for production cost savings due to information sharing about learning by doing between plants in his study of the adoption of thin slab casting in the steel industry ghemawat 1995 1997 finds that nucor achieved cost savings due to information sharing between plants regarding both construction and production costs however he attributes these multiplant economies to specific aspects of nucor s organizational structure and observes that other steel firms with different organizational structures did not achieve these same cost savings given these conflicting results the analysis in this article assumes that if there are multiplant economies they take the form of savings in nonproduction costs in this case a large firm need not have a greater incentive to adopt first its increase in profit from the adoption of a success in all its plants is certainly greater however the existence of nonproduction cost economies can reduce the incentive of a large firm to adopt first suppose there are two firms a large firm with two plants and a small firm with one plant also suppose that when the innovation is first installed in a plant the adopter must shut down that plant for a finite amount of time in order to learn if the innovation is a success or not this shut down time can be considered as an experimental period during which the firm trains workers produces and tests prototypes attempts to overcome any problems associated with the use of the new technology or makes any necessary changes in its existing organization

bad eggs learning by doing and the choice of technology we model long run economic development through technology adoption under scientific uncertainty about environmental effects there are four possible long run equilibria in a socially planned economy high growth adopt rapidly but abandon damaging technologies once revealed ddt cfcs cautious brake the introduction of new technologies to avoid mistakes genetically modified organisms no growth halt technological progress to preserve secondary knowledge and collapse adopt rapidly without ever abandoning damaging technologies in the base parameterization a short sighted social planner chooses the cautious strategy a far sighted planner chooses the high growth strategy unless damages are irreversible in which case the cautious strategy again dominates regulatory options in the market economy are investigated pollution taxes do not affect the firm s level of precaution if they can only be applied after the adopting firm has reaped the benefits however they do encourage the abandonment of damaging technologies liability rules do affect precaution but may lead to excessive caution or even a no growth trap

female employment and occupational changes in the 1990s how is the eu performing relative to the us abstract this paper provides a comparison of the incidence and composition of female employment both in the eu and in the us despite a significant increase in female labour market participation in the eu about 50 of the difference between the employment rates in the us and the eu can still be attributed to differences in the educational attainments and the employment rates of women aged 25 54 we highlight the main features of female employment in both areas paying particular attention to the differences across age cohorts and educational levels our main findings are as follows i the educational level of the eu female population is slowly converging to that of the us across age cohorts ii the employment rates of less educated women are much lower in the eu than in the us with the exceptions of the scandinavian countries even for women aged 25 34 and iii occupational segregation is lower for the younger highly educated women who seem to be entering more typically male occupations and less typically female occupations although at a higher rate in the us than in the eu

learning mixed equilibria we study learning processes for finite strategic form games in which players use the history of past play to forecast play in the current period in a generalization of fictitious play we assume only that players asymptotically choose best responses to the historical frequencies of opponents past play this implies that if the stage game strategies converge the limit is a nash equilibrium in the basic model plays seems unlikely to converge to a mixed strategy equilibrium but such convergence is natural when the stage game is perturbed in the manner of harsanyi s purification theorem journal of economic literature classification number c72

cournot versus walras in dynamic oligopolies with memory abstract this paper explores the impact of memory in cournot oligopolies where firms learn through imitation of success as suggested in alchian j polit econ 57 1950 211 and modeled in vega redondo econometrica 65 1997 375 as long as memory includes at least one period the long run outcome corresponds to any quantity between the cournot one and the walras one the evolutionary stability of the walrasian outcome relies on interfirm comparisons of simultaneously observed profits i e whether a firm earns more than others in a given period whereas the stability of the cournot nash equilibrium is derived from intertemporal comparisons of profits for each given firm i e whether a deviation pays off for that firm

demand and supply in new markets diffusion with bilateral learning i explore the endogenous joint evolution of demand and supply in new markets firms and consumers learn in a bayesian fashion by observing the behavior of other firms and consumers respectively as a result endogenous information diffusion takes place on both sides of the market in equilibrium entry occurs in waves and its level depends on two distinct informational effects the model identifies an externality that provides a natural explanation for s shaped diffusion paths entry reveals information to the consumers about the value of the new product and thus early waves of entry affect the expected profitability of subsequent entry