the speed of the invisible hand abstract very little attention has been devoted to incorporating dynamic elements into empirical models of market structure and performance consequently there has been little progress in settling the issue of whether the market structure profits relationship is more than just a temporary phenomenon in this study an estimation equation is developed which allows for incomplete adjustment of past profits from expected future profits where expected profits depends on present and expected future changes in market structure the model is estimated pooling panel data across industries the findings indicate that adjustment to abnormal profits is relatively quick market share adjustments are non instantaneous and that inclusion of industry specific effects is important the results suggest that previous studies are susceptible to specification bias from omitted variables

giving in to social pressure in light of recent evidence we develop a theory of charitable giving in which donors feel social pressure from a direct solicitation we show that equilibrium donations are concentrated around a social norm donors below the norm increase giving while those above the norm reduce it despite a higher level of the public good relatively poor and or low altruism givers fare worse under social pressure and would avoid the solicitor at a cost aggregate donor welfare improves to the extent that the added social motive alleviates the underprovision of the public good however overprovision may result our theory therefore predicts a light handed regulation for charitable solicitations which is consistent with their exemption from the popular do not call list in the u s we further show that contrary to pure altruism a more equal income distribution may produce more of the public good in fundraising campaigns where a social norm is not apparent one may emerge endogenously if donors are not too heterogeneous in fact multiple social norms may form which offers a focal point argument for suggested donations

the effects of welfare and tax reform the material well being of single mothers in the 1980s and 1990s abstract the tax and welfare programs that provide income and in kind benefits to single mothers have changed dramatically in recent years these changes began as far back as the mid 1980s and culminated with the 1996 welfare law that ended welfare as we knew it these tax and welfare changes have sharply increased the employment of single mothers and cut welfare rolls however little is know about the effects of these policy changes on the material well being of single mothers and their children studies of those leaving welfare have found that a substantial percentage have problems paying rent purchasing enough food and paying utility bills other studies found a decline in income among the worst off single mothers after 1994 or 1995 the goal of this paper is to examine the material well being of single mothers and their families before and after recent welfare and tax reforms using data from two nationally representative household surveys we examine the consumption patterns of single mothers and their families from 1984 2000 we find that the material conditions of single mothers did not decline in recent years either in absolute terms or relative to single childless women or married mothers this pattern holds for the average single mother as well as for low educated single mothers at both the 15th and 25th percentiles of the consumption distribution in most cases our evidence suggests that the material conditions of single mothers have improved slightly

a re examination of the relationship between industry structure and economic performance the objective of this study is to develop a simultaneous equations model of profitability concentration advertising expenditures and research and development outlays the data used in the estimation are subjected to regression diagnostics in an effort to determine the importance to the estimation results of a subset of the data that can have a disproportionate influence the estimation results especially for the advertising expenditures relationship and the research and development outlays equation do change when a truncated data sample based on the omission of the outliers is used this serves partly to explain why there is some disagreement in the literature on market structure and economic performance with regard to the impact of several economic factors

the effect of safety net programs on food insecurity we investigate to what extent major safety net program benefits affect food insecurity in families we impute program eligibility and benefits in each state for 2001 2009 accounting for cross program eligibility rules we use simulated eligibility and benefits for a nationally representative sample as instruments for imputed eligibility and potential benefits among nonimmigrant low income single parent families 1 000 in potential cash or food benefits reduces the incidence of food insecurity by 1 1 percentage points on a base of 33 percent cash and food both reduce food insecurity the results highlight the importance of jointly considering a full range of safety net programs

fundraising through online social networks a field experiment on peer to peer solicitation abstract two main reasons why people donate to charity are that they have been asked and asked by someone they care about one would therefore expect that charitable organizations could benefit from peer to peer fundraising if they were able to persuade donors to do so for them however little is known on the costs and benefits of asking donors to fundraise we investigate this by implementing a field experiment embedded in an online giving organization s web page in our experiment donors who have completed an online transaction were randomly asked to share having donated by posting on their facebook fb wall or by sending a private message to a friend on fb to further explore the impact of incentives on the willingness to fundraise donors were also assigned to one of three treatments in which the organization added either 0 1 or 5 in the donor s name in exchange for sharing the information we have several findings 1 donors respond to incentives larger add on donations increase the willingness to post having made a donation 2 nuisance costs may be important willingness to post is over two times higher among those already logged into fb 3 the type of ask matters willingness to post via one s wall or via a private message is different 4 there are benefits to incentivizing peer to peer fundraising in increased new donations

rewards to investors in innovative information technology applications first movers and early followers in atms innovative information technology it applications are risky investments unless successful applications provide innovators with exceptional returns these investments would not be justified other than a few case studies there is no evidence that the first movers of successful it applications are rewarded for the risks they bear we present the results of an extensive longitudinal study of the effects of early adoption of automated teller machines atms by banks on market share and income the study spans the period from 1971 to 1983 and includes 2 534 banks from across the united states results indicate that the earliest adopters 1971 through 1973 were able to increase market share with market share gains being sustained for a long time banks that adopted atms between 1974 and 1979 however did not gain market share the results also indicate that early atm adoption enabled banks to increase income and income gains were sustained for a long time these findings support case study evidence that early adoption of new it applications can lead to long term competitive advantages for firms

specifying the dynamics of industry concentration previous studies generally explain changes in concentration by its initial determinants or by changes in its determinants little attention is paid to the dynamic structure of the model this study provides a framework to sort out adjustment effects in a systematic manner the empirical model distinguishes long term from short term effects and estimates the rate of adjustment when concentration deviates from its long term equilibrium level considerable attention has focused on industry concentration as a key element of market structure while earlier empirical studies examined determinants of the level of industry concentration a more recent literature focuses on changes in concentration these more recent papers typically explain intertemporal changes in concentration by the past levels of industry growth concentration advertising intensity and minimum efficient plant size however the dynamic relationship between changes in concentration and the levels of the independent variables has not been explicitly specified caves and porter 1980 have argued that explaining changes in concentration by past levels of market structure variables is tantamount to assuming that the sampled industries are in the process of adjusting to a disequilibrium situation as an alternative they adopt a long term equilibrium approach whereby changes in concentration are explained by lagged changes in the relevant market conditions they find that this approach as a whole was unsuccessful exhibiting low levels of significance and a lack of robustness when the cross section regressions were shifted to different time periods

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

incentive effects of the u s welfare system a review the author would like to acknowledge support for prior work on this topic from the u s department of health and human services and helpful comments from three anonymous referees rebecca blank howard chernick john fitzgerald irwin garfinkel peter gottschalk edward gramlich david greenberg judith gueron james heckman v joseph hotz robert hutchens michael keane frank levy larry mead michael murray robert plotnick anuradha rangarajan philip robins howard rolston jeffrey smith and daniel weinberg all opinions and errors are those of the author alone

desirability of compatibility in the absence of network externalities i compare the incentives firms have to produce individual components compatible with components of other manufacturers instead of systems composed of components that are incompatible with components of competing manufacturers i show that even in the absence of positive consumption externalities network externalities prices and profits will be higher in the regime of compatibility equilibrium total surplus could be higher in either regime both regimes overprovide variety compared to the surplus maximizing solution in today s environment many products are complex specified by a long array of characteristics part of the decision of the firm is to choose if it should break this long array of features into two or more smaller parts and produce the products corresponding to the smaller arrays instead of the product that embodies the full array we will call the products that correspond to these smaller arrays components and the product that corresponds to the full array a system note that components are by their definition complements components produced by different manufacturers are compatible if it is feasible for the consumers to combine them costlessly into a working system in this paper we will assume that there are two components which make up a system we will discuss competition under full compatibility when components produced by all firms are compatible with each other and under incompatibility when no components produced by different firms are compatible and no hybrid systems can exist 2 assuming availability of the same

the impact of federal incentives on the adoption of hybrid electric vehicles in the united states abstract starting in 2004 the federal government in the united states offered several nationwide incentives to consumers to increase the adoption of hybrid electric vehicles this study assesses the effectiveness of the energy policy act of 2005 in this regard using econometric methods and data between 2000 and 2010 our model accounts for network externalities by using lagged sales as an independent variable this approach helps to capture the exponential initial growth associated with the diffusion of new technologies and avoids overestimating the effect of the policy incentives our results show that the energy policy act of 2005 increased the sales of hybrids from 3 to 20 depending on the vehicle model considered in addition we find that this incentive is only effective when the amount provided is sufficiently large

causes and effects of vertical intergration this paper sets out to define new measures of industry average forward and backward integration and incorporate them into an empirical stucture conduct performance model results suggest that integration is encouraged where there are relatively few firms in an industry and if sales are increasing forward integration occurs in reaction to large outgoing distribution margins backward integration acts to increase concentration at least in some parts of the manufacturing sector integratin has a complex and interactive effect on profitability serving sometimes to raise profitability and sometimes to lower it

factors determining participation of the elderly in supplemental security the same low participation rates which plague many welfare programs have been observed among the elderly eligible for supplemental security income ssi a number of hypotheses have been offered to explain the low enrollment but none has attracted universal acceptance in this paper i use the survey of income and program participation sipp to examine the participation of the elderly in ssi because of the high quality of the data i am able to determine eligibility more accurately than in most previous studies in this sample only 56 percent of those whom i determine to be eligible for ssi are presently receiving benefits i model the decision to participate as a probit equation but modify the likelihood function to account for measurement error in the expected benefit the results indicate that participation is primarily determined by the financial situation of the eligible individuals although all those eligible for ssi are poor those with little in the way of other resources are significantly more likely to participate this finding differs from widespread beliefs that eligible individuals are discouraged by the difficulty of the application process or that many are uninformed about the program

concentration changes and large firm small firm efficiency differences evidence from us manufacturing industries 1990 concentration changes and large firm small firm efficiency differences evidence from us manufacturing industries applied economics vol 22 no 1 pp 131 142

welfare for the elderly the effects of ssi on pre retirement labor supply abstract this paper studies pre eligibility age labor market disincentives created by the supplemental security income ssi program asset and income limits might induce individuals nearing the eligibility age to work less we exploit states supplementation of federal ssi benefits to estimate the effects of ssi on pre retirement labor supply using sipp data we find some evidence that generous ssi benefits reduce the pre retirement labor supply and earnings of men who are likely to participate in ssi after retirement as they near the eligibility age especially men who are eligible for early social security benefits which may be used to offset their reduced labor income

trade offs in means tested pension design abstract the means testing of age pension programs allows governments to control the receipt of pension benefits extensive margin and the benefit level intensive margin we investigate how the presence of the extensive margin influences the trade off between protecting the poorer elderly and the economic costs of distorting incentives to work and save of young individuals the means test effect via the extensive margin improves the insurance aspect but introduces opposing impacts on incentives that potentially have ambiguous welfare outcomes we characterize combinations of the maximum pension benefit and taper rate that balance the negative incentive effects and positive insurance effects

adoptions and orphans in the early microcomputer market in this paper we examine the development of the microcomputer market in the early 1980s cp m a widely adopted operating system was orphaned by the user and the development communities a new operating system dos and a new hardware platform the ibm pc became the predominant industry standard we examine the statistical relationship between data that reflects hardware and software sales for the competing platforms we conclude that the economic processes underlying the development of dos differed from those underlying cp m and that many of these differences related to the role of software development

the determinants of technology adoption the case of the banking firm using data on the adoption of automatic teller machines by firms in the banking industry this study examines the relationship between the decision to adopt new technology and its determinants since banking firms differ considerably in terms of the competitive environments in which they operate focusing on this one innovation in this industry allows a stronger test of the relationship between market structure and the adoption of new technology than has been previously conducted using a failure time estimation procedure we find that larger banks and banks operating in more concentrated local banking markets register a higher conditional probability of adopting this new technology all else equal we also find that other results are consistent with the underlying model and that the bank s regulatory environment shapes its adoption decision in plausible ways

how does incompatibility affect prices evidence from atm s if consumers value mix and match combinations of network complements incompatibility between different sellers components should affect prices in atm markets a 1996 governance change exogenously generated such incompatibility by allowing banks to impose surcharges when other banks deposit customers use their atm s in our data incompatibility makes the relationship between deposit account pricing and own atm s more positive and makes the relationship between deposit account pricing and competitors atm s more negative the level effect on prices is positive the pattern of results is more pronounced in high population density markets where customers may care more about atm s

excusing selfishness in charitable giving the role of risk decisions involving charitable giving often occur under the shadow of risk a common finding is that potential donors give less when there is greater risk that their donation will have less impact while this behaviour could be fully rationalized by standard economic models this article shows that an additional mechanism is relevant the use of risk as an excuse not to give in a laboratory study participants evaluate risky payoffs for themselves and risky payoffs for a charity when their decisions do not involve tradeoffs between money for themselves and the charity they respond very similarly to self risk and charity risk by contrast when their decisions force tradeoffs between money for themselves and the charity participants act more averse to charity risk and less averse to self risk these altered responses to risk bias participants towards choosing payoffs for themselves more often consistent with excuse driven responses to risk additional results support the existence of excuse driven types

the effect of expanding medicaid eligibility on supplemental security income program participation abstract low income adults without dependent children have historically had few paths to obtain public health insurance unless they qualified for supplemental security income ssi cash benefits because of a disability however in states that expand their medicaid programs childless adults may obtain medicaid without undergoing an intensive ssi disability review process and with substantially higher income and assets than the ssi program allows this expanded availability of medicaid coverage independent of ssi participation creates an opportunity to increase earnings and savings without jeopardizing health insurance coverage in this paper we use the natural experiments created by state decisions to expand medicaid to nondisabled nonelderly adults without dependent children to study the effect of decoupling medicaid eligibility and cash assistance using a difference in differences study design we collected data on the income eligibility limits enrollment caps and coverage characteristics of state medicaid expansions to childless adults from 2001 to 2013 we combine these data with the nationally representative american community survey to estimate the effects of state expansion on ssi participation we find relative declines in ssi participation of 0 17 percentage points on average after the introduction of medicaid coverage for childless adults a 7 relative decrease this finding suggests the potential for small but important efficiency gains from separating ssi and medicaid eligibility

the interaction of public retirement income programs in the united states around 1 2 million elderly individuals currently receive income through the supplemental security income ssi program a welfare program intended to provide income assistance to individuals age 65 or above whose earnings histories do not support an adequate retirement benefit under the old age insurance oai component of social security in this paper we explain how the two programs interact and present basic empirical evidence on how this interaction affects the timing of a first oai claim which may take place as early as age 62 we are fortunate to have unusually complete data on individuals experiences with both the oai and ssi systems due to access to administrative data from the social security administration ssa matched to individuals in the surveys of income and program participation sipp by special arrangement our essential point is that ssi creates incentives for individuals to claim their oai benefits earlier than they otherwise would two factors underlie this first the availability of an early i e pre age 65 retirement option in oai makes ssi participation itself more attractive to those who are oai qualified the ability to combine early oai retirement with later ssi participation enhances the value of participating in ssi second the ssi benefit computation formula creates strong financial incentives to claim oai as early as possible given a person plans to enter ssi and is qualified for oai both of these phenomena are generated by the form of the ssi benefit formula as is typical in a welfare program other income sources are subject to a heavy implicit tax there is also an asset limit for ssi eligibility which we ignore in the interests of simplicity see neumark and powers 1998 for an empirical analysis of this feature in general monthly ssi benefits are reduced dollar for dollar with other income beyond the first 20 two thirds of ssi recipients receive oai income almost none receive private pension income or earnings so most face a 100 percent marginal tax rate on their social security retirement benefits due to participation in the ssi program theory predicts that this implicit confiscatory tax imposed by ssi on oai benefits above 20 discourages work prior to turning age 65 to the extent that people work to enhance postretirement income neumark and powers 2000 the constraint on acting upon the incentives to reduce labor supply prior to age 65 is the maintenance of current consumption clearly this may be a binding constraint for the sorts of lifetime poor individuals who participate in ssi in old age now consider that people may claim oai benefits as early as age 62 early oai benefits enable prospective ssi recipients to curtail their labor supply in the years prior to ssi participation enhancing the value of the ssi program from a lifetime utility perspective while in the absence of ssi the actuarial reduction in oai benefits for early retirement might discourage early claims this is not the case under ssi when ssi determines the government old age transfer actuarial reductions are effectively lifted at age 65 implying that there are no long run adverse financial consequences of making an early first old age insurance oai claim in fact the rules strongly encourage future ssi recipients to claim oai early if they powers institute of government and public affairs and department of economics university of illinois 1007 w nevada st urbana il 61801 e mail epowers uiuc edu neumark public policy institute of california 500 washington st suite 800 san francisco ca 94111 and national bureau of economic research this research was supported by grants from the u s social security administration to the michigan retirement research center and the center for retirement research at boston college and nia grant 1 r01 ag17619 01a2 the opinions and conclusions are solely those of the authors and should not be construed as representing the opinions or policy of any agency of the federal government the centers or the public policy institute of california the authors thank sarah jackson for excellent research assistance and alison del rossi for comments 1 people may also enter ssi through disability we restrict our attention to the aged component

the effects of welfare vehicle asset rules on vehicle assets before 1996 households were typically ineligible for welfare if they had assets worth more than 1000 where 1500 from each vehicle s value was excluded from this determination however the 1996 welfare reform act began allowing states to increase their asset limits and vehicle exclusions this may prompt low income households to reallocate resources to or from vehicles we examine the effects of state vehicle asset rules on vehicle assets results show that liberalizing asset rules increases vehicle assets and that this increase is driven largely by eligible individuals increasing vehicle assets with no evidence indicating that ineligible individuals reduce vehicle assets to become eligible

market dynamics and dichotomy evidence from taiwanese manufacturing in taiwan a dichotomous market structure is closely related to the progress of economic development the purpose of the present article is to examine the market dynamics and dichotomous nature of taiwanese manufacturing a model of dynamic adjustment of industry structure is considered when both the speed of adjustment and the long run market concentration are allowed to vary across industries we use 118 four digit manufacturing industries for empirical analysis of our models spanning between 1981 and 1991 empirical findings show that both the speed of adjustment and long run industry concentration are predominantly determined by minimum efficient scale the speed of adjustment is much faster in a small open economy like taiwan compared to mature economies like the us and australia in addition the dichotomous nature of the market is supported in our findings for both periods viz 1981 1986 and 1986 1991 albeit weaker for the later period

dynamic analysis on market structure of china s coal industry abstract according to industrial organization theory market structure is a crucial factor to market performance based on the var model and the data from 1994 to 2014 we revealed the dynamic response route of the market structure to these factors and the change process of contribution rate of these factors to the market structure it shows that market structure is inertial adjustment technology advance and industry policy have continuous effects on improvement of market concentration ratio market size and production scale have sustained negative effects on market concentration ratio fixed capital has barrier effect which is mainly the entry barrier effect at the beginning and then the exit barrier effect continues to play a leading role therefore the government has no need to introduce special policies to encourage merger or expansion on the capacity as enterprises would do it spontaneously it is necessary to make market access system stricter to improve exit compensation mechanism and to promote technological innovation all these policies need dynamic adjustment based on the stages of economic cycle

industrial concentration and competition in malaysian manufacturing industrial concentration is the most widely studied area among various elements of market structure in the industrial organization literature this paper is a first attempt to analyse the determinants of changes in industry concentration over time in the case of malaysia using a partial adjustment model a cross sectional analysis is carried out against a sample of manufacturing industries between 1986 and 1996 domestic factors in influencing competition e g capital intensity advertising intensity and market size are found to be significant in most cases to explain the level of concentration considering variable rate of adjustment of concentration an increase in labour productivity of large firms and high entry rates are found to be significant for faster adjustment towards equilibrium level compared with other developed countries the annual rate of structural adjustment is found to be slow in the case of malaysian manufacturing

using the medicare buy in program to estimate the effect of medicaid on ssi participation aaron s yelowitz this article assesses the importance of receiving supplemental health insurance on participation in supplemental security income ssi for the elderly the implementation of the qualified medicare beneficiary qmb program offered a substitute for medicaid and expanded health insurance eligibility to a higher income level using a sample of elderly respondents aged 66 to 75 i find that the qmb program reduced ssi participation more than half of the qmb participants were previously covered by ssi and medicaid the calculations suggest that the qmb program was not as expensive as it might first appear because of reductions in ssi expenditure jel h53 138 j14 i introduction the supplemental security income ssi program in the united states provides assistance to elderly blind and disabled individuals who are poor it is federally financed and administered by the social security administration although much more attention has been focused on the former aid to families with dependent children afdc program which primarily targets poor single parent families more money was spent on cash relief for ssi recipients in 1993 23 6 billion compared to 22 3 billion 1 in addition to cash ssi recipients receive supplemental health insurance coverage for medicare similar to private medigap policies through the medicaid program this provides a second important benefit to ssi recipients in fiscal year 1993 medicaid expenditure for elderly categorically needy ssi recipients amounted to 14 1 billion 2 several studies have examined the importance of health insurance for working age adults in the labor market 3 in addition the effects of recent medicaid expansions for younger populations have been extensively studied 4 little is known however about the quantitative importance of medicaid on the ssi participation of the elderly the key obstacle in assessing this effect is that until recently medicaid eligibility had been closely related to ssi eligibility in most states this study analyzes the introduction of the qualified medicare beneficiary qmb program enacted in different states from 1987 to 1992 which offered supplemental health insurance coverage to the elderly without the need to participate in ssi the qmb program offered some of the same medicare cost sharing benefits that an elderly ssi recipient would receive from medicaid including the payment of medicare premiums deductibles and copayments 5 moreover the qmb program expanded medicaid coverage to individuals with higher inc omes and assets than the ssi program 6 the primary goal of this article is to document the link between the qmb program and the decision to participate in ssi i find that raising the income limit in qmb program significantly reduces ssi participation particularly among african americans and the less educated the coefficient estimates suggest that in the absence of the qmb buy in program ssi participation would have been 45 higher in 1992 than it actually was the caseload growth in the elderly ssi population would have looked very similar to the caseload growth of the disabled 851 population a group not eligible for qmb in addition the qmb program was considerably less expensive than one would infer from simply calculating the increased health care expenditure because of reductions in ssi expenditure for cash benefits the rest of the article is arranged as follows section ii outlines some relevant features of the ssi medicaid and qmb programs in particular it reviews how the income eligibility limits for qmb and ssi are computed the difference between those limits is a measure of how closely are medicaid and ssi linked it will subsequently be used as the key independent variable in the regression analysis this section also shows the cross sectional and time series variation in the qmb program section iii models the potential effects on ssi participation of the introduction of the qmb program and considers the role of information

profit entry and changes in concentration abstract the simultaneity between profit entry and changes in concentration is examined the sample includes 481 observations on 4 digit industries over the years 1972 1977 and 1977 1982 results show that profits respond positively to entry barriers and initial concentration net entry responds positively to initial profits and responds negatively to entry barriers concentration moves toward its steady state level but the rate of adjustment is very slow the competitive process left on its own does not seem to move quickly toward equilibrium

brother can you spare a dime peer pressure in charitable solicitation abstract while the effects of peer pressure in charitable giving have been of considerable interest to social scientists there is little empirical evidence on the magnitude of these effects a correlation between giving or volunteering by one s peers and one s own giving can be driven by self selection into groups common shocks that inspire both the solicitor to ask and the individual to give or social influence using data from a university this paper analyzes whether alumni are more likely to give and give larger amounts when they are solicited by someone with whom they have social ties freshman year roommate assignments and the structure of the university s giving campaigns are used to overcome problems of selection and common shocks social ties play a strong causal role in the decision to donate and the average gift size additionally a solicitor s request is much more effective if he or she shares characteristics such as race with the alumnus being solicited

strategic incompatibility in atm markets abstract we test whether firms use incompatibility strategically using data from atm markets high atm fees degrade the value of competitors deposit accounts and can in principle serve as a mechanism for siphoning depositors away from competitors or for creating deposit account differentiation our empirical framework can empirically distinguish surcharging motivated by this strategic concern from surcharging that simply maximizes atm profit considered as a stand alone operation the results are consistent with such behavior by large banks but not by small banks for large banks the effect of incompatibility seems to operate through higher deposit account fees rather than increased deposit account base

sunk costs and regulation in the u s pesticide industry abstract this paper examines the impact of sunk costs and market demand on the number of innovative companies the u s market share of foreign based firms and merger choice in the u s pesticide industry results are consistent with sutton s 1991 view of sunk costs and market structure in that rising endogenous sunk research costs and exogenous sunk pesticide product regulation costs and declining demand negatively affect the number of firms in the industry have a stronger negative impact on the number of smaller firms and encourage foreign based firm expansion

turbulence in growing and declining industries turbulence over the industry life cycle is examined for the case of portugal using the lowest possible level of industry aggregation thus allowing for the use of panel data to study the evolution of product markets replacement of exiting firms by subsequent entrants plays a primary role in generating turbulence in high growth markets while displacement of incumbents by recent entrants is the main selection force in declining markets as the industry life cycle progresses trial and error entry and entry mistakes decrease and turbulence subsides

the dynamics of market structure abstract in this paper changes in market concentration are modelled in terms of long run steady state levels and the adjustment towards them both the speed of adjustment and the long run levels of concentration are allowed to vary across industries non linear three stage least squares estimates for allowing for the endogeneity of profits and advertising for 184 u s industries 1963 1967 suggest that both the speed of adjustment and the levels of concentration in the long run are largely determined by minimum efficient scale

the effect of means tested income support for the elderly on pre retirement saving evidence from the ssi program in the u s abstract we attempt to draw inferences about behavioral responses to means tested income support for the elderly by examining the effects on saving of the supplemental security income ssi program for the aged in the u s part of this program provides payments to the poor elderly operating as a means tested public retirement program we exploit state level variation in ssi benefits to estimate the effects of ssi on saving using data from the 1984 survey of income program participation we find evidence that high ssi benefits reduce saving among households with heads who are approaching the ssi eligibility age and are likely participants in the program

income transfers and assets of the poor contrary to the predictions of the standard life cycle model many low lifetime income households accumulate little wealth relative to their incomes compared to households with high lifetime income i use data from the panel study of income dynamics and a correlated random effects generalized method of moments estimator to decompose the rich poor gaps in wealth to permanent income ratio into the portions attributable to differences in characteristics such as labor market earnings income uncertainty observed demographics and the utilization of transfer programs which may have stringent income and liquid asset tests and those attributable to differences in the estimated coefficients on the respective characteristics the results suggest that wealth to permanent income ratios are increasing in permanent labor income and income uncertainty but that transfer income with or without asset tests discourages liquid asset accumulation the decompositions indicate that most of the rich poor wealth gap is attr

racial and ethnic differences in wealth in the health and retirement study this paper examines wealth data in the health and retirement study hrs in comparison with asset data in other major surveys the quality of hrs asset data is high missing asset data does remain a problem however to which future hrs analysts must remain sensitive evidence is presented showing that it is no accident that asset data are missing and solutions for imputing missing data are developed finally racial and ethnic wealth disparities are large these minority wealth disparities are due in part to differential inheritances and desired bequests as inequities perpetuate themselves across generations the disparities are also due to lower minority incomes poorer health and an excessively narrow definition of wealth that excludes social security and employer pensions authors

the impact of technology adoption on market structure this paper examines the impact of bank adoptions of automated teller machines atms on subsequent levels of concentration in local banking markets the findings suggest that banks have had some success in using atms to attract customers from competitors as a consequence technology adoption s impact on market structure depends upon whether it is the larger or smaller firms within the market that adopt the new technology large firm adoptions increase concentration levels while small firm adoptions tend to reduce them the evidence also suggest that a state of structural disequilibrium seems to be characteristic of banking markets copyright 1990 by mit press

a closer look at the effect of market growth on industries profits everybody talks about the relation of industries profit rates to their markets rates of growth but nobody does anything about it specifically researchers have confirmed the effect of the growth of nominal output on profits in many multivariate studies without specifying closely the hypothesis under test or the measure of demand growth appropriate to test it a profits growth relationship could stem from several mechanisms the lagged adaptation of capacity to unexpected changes in demand reactions of oligopolists to disturbances in their consensus etc these mechanisms how and where they work hold their own normative interest therefore knowing what behavior and what structure lying behind it accounts for the profits growth relationship should do more than improve the specifications of our studies of allocative efficiency it should also expand our knowledge of adaptive processes that are important and hard to observe directly in this paper we shall synthesize the available explanations of why changes in market demand should affect an industry s profits then present a statistical test of the relative significance of the competing explanations

dynamics of market concentration in u s banking 1966 1986 abstract this paper estimates the speed at which local banking market concentration adjusts to its long run equilibrium level long run market concentration is estimated as a function of the attractiveness of entry and regulatory barriers to entry into the market the speed of adjustment is allowed to vary across markets and depends on the deviation of market from normal profits the empirical results from panels of data over 5 10 15 and 20 years show that concentration levels in local banking markets adjust slowly over time markets with unusually high or low profits show significantly more rapid adjustment than other markets over shorter time periods but the differences are small in magnitude legal barriers to entry significantly impede market adjustment over longer time periods

market concentration contestability and sunk costs this paper provides an exploratory assessment of the theory of contestability that is based on a diverse sample of industries and introduces a new important determinant of market concentration the results of the paper indicate that the variables determining the degree of contestability of markets are significant correlates of market concentration sunk costs account for a substantial portion of the sample variance of concentration even after technological factors are controlled for copyright 1990 by mit press

the impact of snap vehicle asset limits on household asset allocation beginning in 2001 states were given the authority to formulate their own rules on how vehicles are counted toward the asset limit in the supplemental nutritional assistance program we exploit differences in timing of the state vehicle asset policy changes to identify their effect on vehicle assets and debts car ownership liquid assets holdings as well as non housing wealth we estimate difference in differences and household fixed effects specifications and find that liberalizing vehicle asset rules increases vehicle assets of households with a high ex ante probability of program participation households also take on more debt to finance their vehicles the increase in car value can be attributed primarily to less educated single parents who already owned a car before the policy change buying more expensive cars

wage declines among older men we examine the evidence on whether real wages decline with age among older men while the general human capital model of wage growth over the life cycle predicts that wages will fall as workers approach the end of their career alternative models of wage growth do not predict these wage declines we find that in longitudinal estimates of age wage profiles wage declines only set in for workers in their 60s furthermore these longitudinal declines are at least partly due to interactions with the social security system the earnings cap or other effects of social security appear to lead some workers to choose jobs and job characteristics associated with lower wages copyright 1996 by mit press

network effects without network externalities abstract the network externalities hypothesis postulates that consumers prefer to purchase brands which are bought by more consumers compared with brands with a low market share in this paper we show that increasing returns to scale in the production of complementary products can substitute for the network externalities assumption we develop a model for the computer industry in which the production of complementary software requires a large fixed cost of development relative to the cost of duplicating and marketing the software the increasing returns to scale in the production of software yields consumers behavior which is very similar to consumers who have preferences exhibiting network externalities

old sick alone and poor a welfare analysis of old age social insurance programmes all individuals face some risk of ending up old sick alone and poor is there a role for social insurance for these risks and if so what is a good programme a large literature has analysed the costs and benefits of pay as you go public pensions and found that the costs exceed the benefits this article instead considers means tested social insurance mtsi programmes for retirees such as medicaid and supplemental security income we find that the welfare gains from these programmes are large moreover the current scale of mtsi in the u s is too small in the following sense if we condition on the current social security programme increasing the scale of mtsi by 1 3 benefits both the poor and the affluent when a payroll tax is used to fund the increase

does means testing welfare discourage saving evidence from a change in afdc policy in the united states abstract this paper provides empirical evidence on the impact of a welfare program s asset test on the saving behavior of its target population the approach exploits a policy experiment the essential federalization of the afdc program s asset testing policy in 1981 data on female headed households from the national longitudinal survey young women are used to test the hypothesis that likely afdc users adjusted their asset stocks in response to this change the findings indicate additional saving between 1978 and 1983 of about 25 cents for each additional 1 increase in the limit in most states

the dynamics of industrial concentration in australian manufacturing abstract a dynamic model of concentration is developed with incomplete and industry specific adjustment to deviations of concentration from its steady state cross sectional analysis is carried out against a sample of 102 australian manufacturing industries at the australian standard industrial classification asic four digit level over the period 1977 78 1984 85 the estimated adjustment is faster than found in studies of the more mature industrial economies and this adjustment is found to significantly increase with reductions in tariff protection there is also empirical support for john sutton s argument that the relationship between concentration and market size depends on whether set up costs are exogenous

a cohort analysis of saving behavior by u s households the aim of this paper is to shed some light in the decline in personal saving rates in the united states in the 1980s for a such a purpose the paper analyses the only u s data set containing information on consumption and income at the household level the consumer expenditure surveys cex from 1980 to 1991 because the cex is not a panel most of the analysis is conducted using average cohort techniques the paper identifies a typical age profile for saving rates such a profile is hump shaped and peaks around age 57 the paper also argues that such a profile was shifted down for the cohorts born between 1920 and 1939 relative to the younger and older cohorts considered these cohorts are the parents of the baby boom generation the paper also argues that these cohort effects can account for a non neglible proportion of the decline in aggregate saving because these cohorts were during the 1980s in the ages when saving rates are typically highest the result is robust to the consideration of several controls and holds for several definitions of consumption the only exception is when durable expenditure is considered as saving rather than consumption

does welfare inhibit success the long term effects of removing low income youth from the disability rolls i estimate the effects of removing low income youth with disabilities from supplemental security income ssi on their earnings and income in adulthood using a regression discontinuity design based on a 1996 policy change in age 18 medical reviews i find that youth who are removed from ssi at age 18 recover one third of the lost ssi cash income in earnings ssi youth who are removed and stay off ssi earn on average 4 400 annually and they lose 76 000 in present discounted observed income over the 16 years following removal relative to those who do not receive a review jel i30 i38 j14 supporters of welfare programs defend them as vital lifelines for those who face barriers to work while critics charge that these programs create perverse incentives to qualify and perpetuate dependency encapsulating this debate is the controversy over the us supplemental security income ssi program a program that provides cash payments and medicaid eligibility to low income children and adults with disabilities and the aged elderly after three decades of rapid expansion ssi is now the largest nonwork based cash welfare program in the united states paying about 50 billion each year to 8 million recipients including 1 3 million children 1 ssi has been singled out by policymakers and the media for potential perverse incentives

fixed costs sunk costs entry barriers and sustainability of monopoly this paper shows that i fixed costs of sufficient magnitude assure the existence of a vector of sustainable prices for the products of a natural monopolist prices making him invulnerable against entry ii nevertheless fixed costs do not constitute barriers to entry that is they need not have undesirable welfare consequences iii indeed in market forms that we call perfectly contestable large fixed costs are completely compatible with many desirable attributes of competitive equilibrium iv sunk costs do however constitute barriers to entry and v finally the profit and welfare consequences of entry barriers are described formally in this paper it is shown that i fixed costs of sufficient magnitude assure the existence of a vector of sustainable prices a set of product prices that make a natural monopolist invulnerable against successful entry ii nevertheless costs that are truly fixed do not constitute barriers to entry that is they do not have the welfare consequences normally attributed to barriers to entry iii indeed there are markets of a form which we call perfectly contestable markets and whose properties may be approximated in practice in which large fixed costs are completely compatible with many if not most of the desirable attributes of competitive equilibrium iv sunk costs do however constitute barriers to entry and v finally the resource allocation problems that stem from fixed costs are formally identical with those that accompany public goods both their sources and their character are the same thus the rationale for public supply of public goods may be no different from that pertaining to nationalization of natural monopolies

do welfare asset limits affect household saving evidence from welfare reform we use data from the panel study of income dynamics to estimate the effect of new saving incentives implemented as part of the 1996 welfare reform on household saving economic theory predicts that loosening asset limits will increase total savings for households with a large ex ante probability of welfare receipt such as female headed households with children we follow a sample of female heads with children and find that in both absolute terms and relative to comparison groups of male heads and female heads without children there has been no effect of welfare policy changes on the saving of at risk households