applying digital analysis to detect fraud an empirical analysis of us marine industry firms have tendency to window dress their financial statements by reporting earnings to achieve reference points represented by n 10 k such practice of reporting rounded earnings is likely due to 1 firms may believe that investors perceive a reported earnings of 1 99 million to be significantly less than 2 0 million and or 2 contracts between firms and stakeholders are likely to express earnings in round numbers auditors have employed more sophisticated digital analysis such as benford s law as part of their fraud detection processes this study investigated the window dressing behaviour among firms in the us marine industry the findings of the study suggest that window dressing is a significant practice among the marine firms however the extent of the pervasiveness of such behaviour is less severe among marine firms than among all publicly listed firms in the entire us economy suggesting that the quality of financial statements of marine companies is higher than the overall population of

teen motherhood and abortion access it is argued that the net effect of any restriction of abortion access on birth rates is an empirical question this study examines the impact of access to abortion on county teenage birth rates birth rates are expected to decrease by 1 among white adolescents aged 15 19 years for a 25 mile increase in the distance to the nearest abortion provider particularly among in wedlock births data are obtained from 1973 88 national natality local area summary files for counties in the us and four other national sources data did not provide useful information on the empirical relationship between access and birth rate for densely populated urban areas cross sectional findings that had omitted variable bias indicate that an increase of 25 miles in distance to a provider was associated with an additional 1 4 births per 1000 white teenage women or a 3 increase in the average teen birth rate of 45 1000 white teenagers the findings from a county fixed effects model that controlled for omitted variable bias indicate that an increase of 25 miles was associated with a reduction in teen births of 0 5 1000 or about 1 of the mean birth rate both medicaid restrictions and parental consent laws were negative and significant and more negative in poor and more isolated counties the state year effects models did not change findings on distance and medicaid restriction effects the effects of changes in timing of laws suggests that laws followed preexisting trends changes in distance to provider were primarily in the first 2 years following the change out of wedlock births were unaffected by changes in distance to providers the out of wedlock teen birth rate increased with a complete ban on abortions fewer wanted births were associated with small restrictions findings imply that closing of clinics during 1977 88 had an impact on teen birth rates of under one tenth of 1 the 20 increase in teen births was unexplained

causes for an asymmetric relation between the price of crude oil and refined petroleum products we revisit the issue of asymmetries in the relation between the price of crude oil and refined petroleum products in the united states an econometric analysis of monthly data indicates that the asymmetric relation between the price of crude oil and motor gasoline is generated by refinery utilization rates and inventory behavior the asymmetric relation between the price of crude oil and home heating oil probably is generated by contractual arrangements between retailers and consumers together these results imply that price asymmetries may be generated by efficient markets under these conditions there is little justification for policy interventions to reduce or eliminate price asymmetries in motor gasoline and home heating oil markets

risk aversion in a dynamic asset allocation experiment we conduct a controlled laboratory experiment in the spirit of merton 1971 in which subjects dynamically choose their portfolio allocation between a risk free and risky asset using the optimal allocation of an investor with hyperbolic absolute risk aversion hara utility we fit the experimental choices to characterize the risk profile of our participants despite substantial heterogeneity decreasing absolute risk aversion and increasing relative risk aversion are the predominant types we also find some evidence of increased risk taking after a gain finally the session level risk attitudes show a different profile than the individual descriptions of risk attitudes

testing for asymmetric pricing in the canadian retail gasoline market abstract this paper applies a threshold regression model to test for asymmetric pricing in the retail gasoline market in canada using weekly data for the period january 1990 to december 1996 we present results for 13 canadian cities for both premium and regular gasoline within the context of an error correction model we test for the presence of asymmetric price behaviour using average changes in crude prices as well as various lags for the change in crude as possible thresholds we are unable to find any evidence to support this view

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

testing a discrete switching disequilibrium model of the uk labour market this paper develops a test procedure for serial correlation for discrete switching disequilibrium models which include both an endogenous price adjustment equation and lagged dependent variables the tests are applied to a model of the u k labor market and the model is respecified in the light of the test results

rockets and feathers the asymmetric speed of adjustment of uk retail gasoline prices to cost changes abstract the paper develops a quadratic quantity adjustment model to test the hypothesis put forward in the recent monopolies and mergers commission report that the speed of adjustment of uk retail gasoline prices to cost changes is more rapid when costs rise than when they fall and that the adjustment path is more concentrated around the mean value on the upswing using data from 1982 to 1989 evidence of faster and more concentrated responses to cost increases were found

regulation and the optimal size and type of abortion provider between 1973 the year the supreme court ruled in roe v wade that women have the right to decide whether or not to terminate their pregnancies and 1982 the number of abortion providers increased by 81 per cent however between 1982 and 1992 a period of increasing state level abortion regulation the number of abortion providers decreased by 18 per cent we know very little about the factors that influence the willingness and ability of hospitals clinics and physicians to provide abortion services over time based on state data from 1978 to 1992 the results of this paper suggest that large abortion providers are better able to compete and survive in the market also clinics and physicians offices appear to be gaining market share relative to hospitals further this paper includes analysis of the impact of state level medicaid funding regulations on the number size and type of abortion provider these results have important implications for women s access to abortion services and thus have impor

retail price cycles and response asymmetry weekly retail gasoline prices in windsor ontario from 1989 to 1994 appear to respond faster to wholesale price increases than to decreases but exhibit a cyclic pattern inconsistent with a common explanation of response asymmetry i reconcile these observations through a model of price cycles prices on the downward portion of the cycle appear insensitive to costs compared with price increases supporting the theory that price decreases result from battles over market share this pattern resembles a faster response to cost increases than to decreases and the conclusion that asymmetry indicates a role for competition policy may be inappropriate jel classification l13 l71 cycles des prix de detail et reponse asymetrique les prix de detail hebdomadaires de la gazoline a windsor ont entre 1989 et 1994 semblent reagir plus vite aux accroissements qu aux chutes des prix de gros mais suivent un pattern cyclique qui ne semble pas consistant avec l explication traditionnelle en termes de reponse asymetrique l auteur reconcilie ces observations a l aide d un modele de cycle de prix les prix dans la portion descendante du cycle semblent insensibles aux variations de couts par comparaison avec les accroissements de prix ce qui supporte la theorie que les chutes de prix resultent de luttes pour les parts de marche le pattern ressemble a celui declenche par une reponse plus rapide aux augmentations qu aux chutes de couts et la conclusion qui voudrait qu on puisse attribuer le tout a l asymetrie des reponses et que donc une intervention de la politique de la concurrence s impose peut etre inappropriee

shell shocked the impact of foreign entry on the gasoline retail market in china abstract since joining the wto in 2001 restrictions on foreign entry into china s energy sector have been steadily reduced we investigate the impact of royal dutch shell s entry on the pricing behavior of three varieties of gasoline in the retail market of china using a difference in difference pairwise estimator we show that a year after entry the average absolute price differential of gasoline between two cities increased by around 1 4 before falling the following year in other words shell s entry caused prices to diverge but only for a short period of time the largest price effect was found for highly refined fuels in western cities similar results are found when we examine the effect of entry of the top four foreign retailers policy implications are discussed

the determinants of hospital size a survivor analysis the meaning and reliability of existing estimates of optimal scale in the production of hospital services are suspect because of the failure to adequately deal with the role of admitting physicians this paper develops estimates of hospital size by studying changes in the size distribution of us short term general hospitals over the period 1971 77 the technique produces size estimates which would be socially optimal only under very strong assumptions but it has the advantage of accounting for the impacts of factors which typically have been ignored in cost function studies of hospital size the analysis reveals substantial differences in survival size among geographic regions a measure of survival size of nonprofit hospitals by state is developed and its determinants are investigated in a multiple regression framework survival size is found to be negatively affected by growth in the profit hospital sector and by the entry of health maintenance organizations while population growth urbanization and a

a theory of dynamic oligopoly ii price competition kinked demand curves and edgeworth cycles we provide game theoretic foundations for the classic kinked demand curve equilibrium and edgeworth cycle we analyze a model in which firms take turns choosing prices the model is intended to capture the idea of reactions based on short run commitment in a markov perfect equilibrium mpe a firm s move in any period depends only on the other firm s current price there are multiple mpe s consisting of both kinked demand curve equilibria and edgeworth cycles in any mpe profit is bounded away from the bertrand equilibrium level we show that a kinked demand curve at the monopoly price is the unique symmetric renegotiation proof equilibrium when there is little discounting we then endogenize the timing by allowing firms to move at any time subject to short run commitments we find that firms end up alternating thus vindicating the ad hoc timing assumption of our simpler model we also discuss how the model can be enriched to provide explanations for excess capacity and market sharing keiiwords tacit collusion markov perfect equilibrium kinked demand curve edgeworth cycle excess capacity market sharing endogenous timing

gas wars retail gasoline price fluctuations this paper examines the retail gasoline price fluctuations known as gas wars weekly prices for the los angeles area were examined for the period from january 2 1968 through december 23 1975 the observed fluctuations were remarkably regular and apparently large ly predictable the data appear consistent with the recent game theory model of e maskin and j tirole in which competing firms produce edgeworth cycles by undercutting each other and eventually relenting copyright 1993 by mit press

asymmetric price adjustments in us gasoline markets impacts of spatial dependence on the rockets and feathers hypothesis gasoline retail prices show sometimes wild asymmetric fluctuations over time we explore the impact of spatial dependence on gasoline retail price formation by using for the first time an asymmetr

state abortion rates the impact of policies providers politics demographics and economic environment abstract this paper uses data on abortion rates by state from 1974 1988 to estimate two stage least squares models with fixed state and year effects restrictions on medicaid funding for abortion are correlated with lower abortion rates in state and higher rates among nearby states a maximal estimate suggests that 19 25 of the abortions among low income women that are publicly funded do not take place after funding is eliminated parental notification laws for teen abortions do not significantly affect aggregate abortion rates a larger number of abortion providers in a state increases the abortion rate primarily through inducing cross state travel

price adjustments by a gasoline retail chain we use daily data to examine price responses in the swedish gasoline market to changes in the rotterdam spot price exchange rates and taxes the distribution of price adjustments by a leading retail chain for the period january 1980 to december 1996 is symmetric with no small adjustments an error correction model shows that in the short run prices gradually move towards the long run equilibrium in response to cost shocks there is some evidence that also in the short run prices are stickier downwards than upwards prices respond more rapidly to exchange rate movements than to the spot market price our analysis emphasizes that to fully understand price adjustments it is necessary to examine data sets where the sample frequency at least matches that of price adjustments

resolving the impasse on hospital scale economics a new approach the existence of scale economies in hospitals in important for both public and managerial policy yet production and cost function studies have found conflicting evidence more recently more sophisticated studies have typically found scale diseconomies which is inconsistent with the views of industry participants and observers in the early 1980s california deregulated both private and public health insurance medical which provides a natural laboratory for examining hospital efficiency using stigler s original and multivariate survivor analysis we resolve the conflict in favour of scale economies and reconcile the controversy the survivorship methodology in simple to apply and a useful tool in conjunction with statistical cost and production studies

econometric models of asymmetric price transmission abstract in this paper we review the existing empirical literature on price asymmetries in commodities providing a way to classify and compare different studies that are highly heterogeneous in terms of econometric models type of asymmetries and empirical findings relative to the previous literature this paper is novel in several respects first it presents a detailed and updated survey of the existing empirical contributions on price asymmetries in the transmission mechanism linking input prices to output prices second this paper presents an extension of the traditional distinction between long run and short run asymmetries to new categories of asymmetries such as contemporaneous impact distributed lag effect cumulated impact reaction time equilibrium and momentum equilibrium adjustment path regime effect regime equilibrium adjustment path each empirical study is then critically discussed in the light of this new classification of asymmetries third this paper evaluates the relative merits of the most popular econometric models for price asymmetries namely autoregressive distributed lags partial adjustments error correction models regime switching and vector autoregressive models finally we use the meta regression analysis to investigate whether the results of asymmetry tests are not model invariant and find which additional factors systematically influence the rejection of the null hypothesis of symmetric price adjustment the main results of our survey can be summarized as follows i each econometric model is specialized to capture a subset of asymmetries ii each asymmetry is better investigated by a subset of econometric models iii the general significance of the f test for asymmetric price transmission depends mainly on characteristics of the data dynamic specification of the econometric model and market characteristics overall our empirical findings confirm that asymmetry in all its forms is very likely to occur in a wide range of markets and econometric models

regulation imperfect competition and the u s abortion market the u s abortion market has grown increasingly concentrated recently while many states tightened abortion laws using data on abortion providers i estimate an equilibrium model of demand price competition entry and exit to capture the effect of regulation on industry dynamics estimates show regulations played an important role in determining the abortion market structure and evolution counterfactual simulations reveal increases in demand aimed regulation were the most important observed factor in explaining recent abortion declines simulating utah s regulatory regime nationally shows tightening abortion restrictions can increase abortions in equilibrium mainly through tilting the competitive landscape toward low price providers

price response asymmetric information and competition we compare predictions from a theoretical model based on the structure of the main outdoor retail market in jerusalem with the results of an empirical analysis of price response to changes in cost we find that firms without adjacent competition exhibit both upward and downward price rigidity an outcome we ascribe to asymmetric information between the consumer and the firm given that previous studies have focused on downward price rigidities of firms with market power our findings highlight the importance of accounting for transitory information asymmetries between the consumer and the firm when studying price rigidity

retail price asymmetries in local gasoline markets the experience of the salt lake city retail gasoline market during the 1989 to 1993 period suggests that there was asymmetric adjustment wholesale and retail price data unique to the salt lake market are used to test for the existence of three types of price asymmetry during this period with respect to the magnitude of the pass through of wholesale price changes evidence of price asymmetry during periods of average weekly wholesale price changes is found however during market shocks the evidence points in the direction of retail price symmetry evidence of asymmetry with respect to the timing and pattern of the retail price response is found for periods of both average and market shock changes since gasoline is purchased by the consumer in local markets conclusions reached by studies of market pricing behaviour that rely on national data may not be relevant for local policy decisions this appears to be the case for the salt lake city market

sequential moves and tacit collusion reaction function cycles in a finite pricing duopoly abstract this paper analyzes a finite horizon sequential move pricing duopoly restricting attention to markov strategies the solution yields stationary patterns independent of initial conditions where the reaction functions follow cycles of three periods the market price never settles down and is at all times strictly above marginal cost long run average industry profits are approximately 5 6 of the monopoly level these results demonstrate that neither a long horizon nor non markovian strategies are required for persistent profits in dynamic price competition games journal of economic literature classification numbers c73 d43 l13

do gasoline prices respond asymmetrically to crude oil price changes the authors test and confirm that retail gasoline prices respond more quickly to increases than to decreases in crude oil prices among the possible sources of this asymmetry are production inventory adjustment lags and market power of some sellers by analyzing price transmission at different points in the distribution chain the authors attempt to shed light on these theories spot prices for generic gasoline show asymmetry in responding to crude oil price changes which may reflect inventory adjustment effects asymmetry also appears in the response of retail prices to wholesale price changes possibly indicating short run market power among retailers

the impact of state abortion restrictions on minors demand for abortions this study uses a weighted least squares model and a fixed effects model to estimate the impact of parental consent laws and laws governing medicaid funding of abortions on the adolescents demand for abortion in the united states during 1978 90 the focus is on adolescent pregnancy because 12 of total legal abortions in 1987 were to adolescents aged under 18 years the rate of abortion and types of abortion law range widely between states data are obtained from the us center for disease control on reported abortions from the naral foundation on the dates of actual enforcement restrictions and from the alan guttmacher institute on abortion providers the empirical model is based on a model developed by grossman and joyce proxy measures are used to represent abortion sentiment fixed effects models indicated that there was a decline of 13 17 in adolescents demand for abortion in states with enforced parental involvement laws compared to states without enforced laws the results implied a 9 15 decline in adolescents demand for abortion in states that restricted medicaid funding of abortion compared to states that did not there was a positive association between abortion demand and income and between abortion demand and the availability of abortion providers the inclusion of the abortion sentiment proxies did not change the signs and magnitudes of the impact very much in the fixed effects models it is posited that the negative impacts of abortion restrictions on adolescent abortion demand cannot be attributed to unobserved heterogeneity four methods of modeling are used to account for the potential role of unobserved heterogeneity