THE INTERNATIONAL DIMENSION OF PRODUCTIVITY AND DEMAND SHOCKS IN THE US ECONOMY

This paper analyzes the cross‐country effects of productivity and demand disturbances in the United States identified with sign restrictions based on standard theory. Productivity gains in US manufacturing increase US consumption and investment vis‐à‐vis foreign countries, resulting in a trade deficit and higher international prices of US goods, despite the rise in their supply. Financial adjustment works via a higher global value of US equities, real dollar appreciation, and an expansion of US gross foreign liabilities as well as assets. Positive demand shocks to US manufacturing also increase investment and cause a real dollar appreciation, but have limited effects on the trade balance and net foreign assets. Our findings emphasize the importance for macroeconomic interdependence of endogenous fluctuations in aggregate demand across countries in response to business cycle shocks.     

Prices,Markups, and Trade Reform

This paper examines how prices, markups, and marginal costs respond to trade liberalization. We develop a framework to estimate markups from production data with multi‐product firms. This approach does not require assumptions on the market structure or demand curves faced by firms, nor assumptions on how firms allocate their inputs across products. We exploit quantity and price information to disentangle markups from quantity‐based productivity, and then compute marginal costs by dividing observed prices by the estimated markups. We use India's trade liberalization episode to examine how firms adjust these performance measures. Not surprisingly, we find that trade liberalization lowers factory‐gate prices and that output tariff declines have the expected pro‐competitive effects. However, the price declines are small relative to the declines in marginal costs, which fall predominantly because of the input tariff liberalization. The reason for this incomplete cost pass‐through to prices is that firms offset their reductions in marginal costs by raising markups. Our results demonstrate substantial heterogeneity and variability in markups across firms and time and suggest that producers benefited relative to consumers, at least immediately after the reforms.     

Equilibrium Labor Turnover,Firm Growth,and Unemployment

This paper considers equilibrium quit turnover in a frictional labor market with costly hiring by firms, where large firms employ many workers and face both aggregate and firm specific productivity shocks. There is exogenous firm turnover as new (small) startups enter the market over time, while some existing firms fail and exit. Individual firm growth rates are disperse and evolve stochastically. The paper highlights how dynamic monopsony, where firms trade off lower wages against higher (endogenous) employee quit rates, yields excessive job‐to‐job quits. Such quits directly crowd out the reemployment prospects of the unemployed. With finite firm productivity states, stochastic equilibrium is fully tractable and can be computed using standard numerical techniques.     

The Impact of Trade on Intra‐Industry Reallocations and Aggregate Industry Productivity

This paper develops a dynamic industry model with heterogeneous firms to analyze the intra‐industry effects of international trade. The model shows how the exposure to trade will induce only the more productive firms to enter the export market (while some less productive firms continue to produce only for the domestic market) and will simultaneously force the least productive firms to exit. It then shows how further increases in the industry's exposure to trade lead to additional inter‐firm reallocations towards more productive firms. The paper also shows how the aggregate industry productivity growth generated by the reallocations contributes to a welfare gain, thus highlighting a benefit from trade that has not been examined theoretically before. The paper adapts Hopenhayn's (1992a) dynamic industry model to monopolistic competition in a general equilibrium setting. In so doing, the paper provides an extension of Krugman's (1980) trade model that incorporates firm level productivity differences. Firms with different productivity levels coexist in an industry because each firm faces initial uncertainty concerning its productivity before making an irreversible investment to enter the industry. Entry into the export market is also costly, but the firm's decision to export occurs after it gains knowledge of its productivity.     

Collusion With Persistent Cost Shocks

We consider a dynamic Bertrand game in which prices are publicly observed and each firm receives a privately observed cost shock in each period. Although cost shocks are independent across firms, within a firm costs follow a first‐order Markov process. We analyze the set of collusive equilibria available to firms, emphasizing the best collusive scheme for the firms at the start of the game. In general, there is a trade‐off between productive efficiency, whereby the low‐cost firm serves the market in a given period, and high prices. We show that when costs are perfectly correlated over time within a firm, if the distribution of costs is log‐concave and firms are sufficiently patient, then the optimal collusive scheme entails price rigidity: firms set the same price and share the market equally, regardless of their respective costs. When serial correlation of costs is imperfect, partial productive efficiency is optimal. For the case of two cost types, first‐best collusion is possible if the firms are patient relative to the persistence of cost shocks, but not otherwise. We present numerical examples of first‐best collusive schemes.     

FROM FLEXIBILITY TO INSECURITY: HOW VERTICAL SEPARATION AMPLIFIES FIRM‐LEVEL UNCERTAINTY

This article presents a model where firms may endogenously externalize part of their production process. We start from the premise that adaptation to uncertainty cannot be contracted upon in the worker/employer relationship. Vertical separation then balances flexibility gains against hold‐up costs of opportunistic behavior by outside contractors. In equilibrium, the degree of separation is shown to depend on the degree of product market competition, contractor's bargaining power, and the volatility of demand shocks. Our main result is that an increase in the degree of vertical separation amplifies the elasticity to demand shocks of firms' sales and employment. It does not, however, amplify aggregate uncertainty. Evidence from firm‐level data is shown to be largely consistent with the main implications of our theory. (JEL: L16, L23, L24)     

Labour‐market Institutions and Macroeconomic Shocks

Abstract. Macroeconomic shocks and labour‐market institutions jointly determine employment growth and economic performance. The effect of shocks depends on the nature of these institutions and the effect of institutional change depends on the macroeconomic environment. It follows that a given set of institutions may be appropriate in one epoch and not in another. We derive a dynamic model of labour demand in which the effect of firing costs on labour demand depends on the macroeconomic environment: when the level of macroeconomic activity is expected to drop and/or the trend rate of productivity growth is small, a rise in firing costs affects mainly (and adversely) the hiring decision and not the layoff decision. This makes firing costs harmful to employment when it may appear most appropriate. In contrast, firing costs can raise employment during periods of high growth and positive shocks. Our hypothesis is supported by empirical results using OECD data.     

An Empirical Equilibrium Model of a Decentralized Asset Market

I estimate a search‐and‐bargaining model of a decentralized market to quantify the effects of trading frictions on asset allocations, asset prices, and welfare, and to quantify the effects of intermediaries that facilitate trade. Using business‐aircraft data, I find that, relative to the Walrasian benchmark, 18.3 percent of the assets are misallocated; prices are 19.2 percent lower; and the aggregate welfare losses equal 23.9 percent. Dealers play an important role in reducing trading frictions: In a market with no dealers, a larger fraction of assets would be misallocated, and prices would be higher. However, dealers reduce aggregate welfare because their operations are costly, and they impose a negative externality by decreasing the number of agents' direct transactions.     

Identification in Differentiated Products Markets Using Market Level Data

We present new identification results for nonparametric models of differentiated products markets, using only market level observables. We specify a nonparametric random utility discrete choice model of demand allowing rich preference heterogeneity, product/market unobservables, and endogenous prices. Our supply model posits nonparametric cost functions, allows latent cost shocks, and nests a range of standard oligopoly models. We consider identification of demand, identification of changes in aggregate consumer welfare, identification of marginal costs, identification of firms' marginal cost functions, and discrimination between alternative models of firm conduct. We explore two complementary approaches. The first demonstrates identification under the same nonparametric instrumental variables conditions required for identification of regression models. The second treats demand and supply in a system of nonparametric simultaneous equations, leading to constructive proofs exploiting exogenous variation in demand shifters and cost shifters. We also derive testable restrictions that provide the first general formalization of Bresnahan's (1982) intuition for empirically distinguishing between alternative models of oligopoly competition. From a practical perspective, our results clarify the types of instrumental variables needed with market level data, including tradeoffs between functional form and exclusion restrictions.     

供给与需求驱动型原油价格变动对股票市场的多时间尺度影响研究

不同时间尺度下，供给和需求驱动型原油价格变动对股票市场的影响具有差异性，本文结合小波变化及向量自回归模型，从影响方向、影响强度及影响持续时间三个角度对这种差异性展开研究。首先，在多时间尺度下识别供给和需求驱动型原油价格变动；随后，就不同类型原油价格变动对全球综合股指的动态影响进行分析。结果发现：1）两类原油价格变动对股票市场在短、中及长期下均有显著影响，但需求驱动型原油价格变动在超短期（尺度1：2-4个月）和超长期（尺度6：64-128个月）下对股票市场没有显著影响；2）两类原油价格变动对股票市场的影响方向在短期和中期下具有随机性，在长期下具有正向影响；3）两类原油价格变动对股票市场的影响强度在短期和中期较在长期要高出至少60%；4）两类原油价格变动对股票市场的影响时间随着时间尺度的增长而增长，由短期下的20个月左右延长至长期下的60个月以上。     

Demand–Supply Mismatches and Stock Market Performance: A Retailing Perspective

We provide empirical evidence that the volatility of inventory productivity relative to the volatility of demand is a predictor of future stock returns in a sample of publicly listed U.S. retailers over the period 1985–2013. This key performance indicator, entitled demand–supply mismatch (DSM), captures the fact that low variation in inventory productivity relative to variation in demand is indicative of the superior synchronization of demand‐ and supply‐side operations. Applying the Fama and French (1993) three‐factor model augmented with a momentum factor (Carhart 1997), we find that zero‐cost portfolios formed by buying the two lowest and selling the two highest quintiles of DSM stocks yield abnormal stock returns of up to 1.13%. These strong market anomalies related to DSM are observed over the entire sample period and persist after controlling for alternative inventory productivity measures and firm characteristics that are known to predict future stock returns. Further, we reveal that DSM is indicative of lower future earnings and lower sales growth and provide evidence that the observed market inefficiency results from investors’ failure to incorporate all of the information that inventory contains into the pricing of stocks.     

Committed Versus Contingent Pricing Under Competition

Should capacitated firms set prices responsively to uncertain market conditions in a competitive environment? We study a duopoly selling differentiated substitutable products with fixed capacities under demand uncertainty, where firms can either commit to a fixed price ex ante, or elect to price contingently ex post, e.g., to charge high prices in booming markets, and low prices in slack markets. Interestingly, we analytically show that even for completely symmetric model primitives, asymmetric equilibria of strategic pricing decisions may arise, in which one firm commits statically and the other firm prices contingently; in this case, there also exists a unique mixed strategy equilibrium. Such equilibrium behavior tends to emerge, when capacity is ampler, and products are less differentiated or demand uncertainty is lower. With asymmetric fixed capacities, if demand uncertainty is low, a unique asymmetric equilibrium emerges, in which the firm with more capacity chooses committed pricing and the firm with less capacity chooses contingent pricing. We identify two countervailing profit effects of contingent pricing under competition: gains from responsively charging high price under high demand, and losses from intensified price competition under low demand. It is the latter detrimental effect that may prevent both firms from choosing a contingent pricing strategy in equilibrium. We show that the insights remain valid when capacity decisions are endogenized. We caution that responsive price changes under aggressive competition of less differentiated products can result in profit‐killing discounting.     

The Granular Origins of Aggregate Fluctuations

This paper proposes that idiosyncratic firm‐level shocks can explain an important part of aggregate movements and provide a microfoundation for aggregate shocks. Existing research has focused on using aggregate shocks to explain business cycles, arguing that individual firm shocks average out in the aggregate. I show that this argument breaks down if the distribution of firm sizes is fat‐tailed, as documented empirically. The idiosyncratic movements of the largest 100 firms in the United States appear to explain about one‐third of variations in output growth. This “granular” hypothesis suggests new directions for macroeconomic research, in particular that macroeconomic questions can be clarified by looking at the behavior of large firms. This paper's ideas and analytical results may also be useful for thinking about the fluctuations of other economic aggregates, such as exports or the trade balance.     

The interaction between stock prices and corporate investment: is Europe different?

I find limited evidence of firm learning from stock prices in Europe and uncover multifaceted complementarities between firm informational and operating environments in determining investment sensitivity to stock prices. Specifically, European firms seemingly do not shift away from their own (peer) stock prices even in instances in which their peers’ (own) stock prices become relatively more informative about firms’ fundamentals. This is consistent with European managers adopting more conservative strategies relative to their U.S.-based peers, and stock prices being less revealing in Europe than in the U.S. Furthermore, while a firm may attach equal weight to both its own stock prices and peer price innovations when peer firms are relatively smaller, investment responds more positively to peers’ price shocks than to that firm’s own stock prices when peers are relatively larger. Interestingly, investment sensitivity to peers’ stock prices decreases in peers’ market share, operating performance, and capital intensity. The decrease is accentuated when peer firms have more informative stock prices and are industry leaders or more capital intensive, thereby signaling perceived reduced growth opportunities. Broadly, these results imply that the specifics of the interaction between stock prices and firm behavior in the U.S. do not necessarily generalize to Europe. More important, these different learning patterns are partly attributable to differences in the amount of internal information, which in turn depends on country-level institutional infrastructures.     

Inequality and Unemployment in a Global Economy

This paper develops a new framework for examining the determinants of wage distributions that emphasizes within‐industry reallocation, labor market frictions, and differences in workforce composition across firms. More productive firms pay higher wages and exporting increases the wage paid by a firm with a given productivity. The opening of trade enhances wage inequality and can either raise or reduce unemployment. While wage inequality is higher in a trade equilibrium than in autarky, gradual trade liberalization first increases and later decreases inequality.     

Farms,Families, and Markets: New Evidence on Completeness of Markets in Agricultural Settings

The farm household model has played a central role in improving the understanding of small‐scale agricultural households and non‐farm enterprises. Under the assumptions that all current and future markets exist and that farmers treat all prices as given, the model simplifies households' simultaneous production and consumption decisions into a recursive form in which production can be treated as independent of preferences of household members. These assumptions, which are the foundation of a large literature in labor and development, have been tested and not rejected in several important studies including Benjamin (1992). Using multiple waves of longitudinal survey data from Central Java, Indonesia, this paper tests a key prediction of the recursive model: demand for farm labor is unrelated to the demographic composition of the farm household. The prediction is unambiguously rejected. The rejection cannot be explained by contamination due to unobserved heterogeneity that is fixed at the farm level, local area shocks, or farm‐specific shocks that affect changes in household composition and farm labor demand. We conclude that the recursive form of the farm household model is not consistent with the data. Developing empirically tractable models of farm households when markets are incomplete remains an important challenge.     

Optimal Pricing of Two Successive‐Generation Products with Trade‐in Options under Uncertainty

To entice consumers to purchase both current and next generation products, many manufacturers and retailers offer trade‐in programs that allow buyers of the first generation product to trade‐in the product and purchase the new generation product at a lower price. By considering the interactions between “forward‐looking” consumers and a firm when a trade‐in program is offered, we analyze a two‐period dynamic game to determine the optimal prices of two successive‐generation products in equilibrium, and examine the conditions under which trade‐in programs are beneficial to the firm. Our model incorporates market heterogeneity (valuation of the first generation product varies among the consumer population), product uncertainty (the incremental value of the new product is uncertain before its introduction), and consumers' forward‐looking behavior (consumers take future product valuation and prices into consideration when making purchasing decisions). With the trade‐in option, we show that consumers are willing to pay a price that is higher than their valuations of the current product. Furthermore, trade‐in programs are more beneficial to the firm when: (i) the durability of the current product is high; (ii) the market heterogeneity is low; or (iii) the uncertainty level (or the expected incremental value) of the new product is high. Finally, when the incremental value of the new product is more uncertain, consumers are more willing to purchase the current product because of the “option” value of the trade‐in programs and thus trade‐in programs can be more beneficial to the firm in this case.     

Inept or Badly Matched? — Effects of Educational Mismatch in the Labor Market

Negative wage effects of educational mismatch have become a stylized fact. Whether these are explained by differences in unobserved productivity or poor matching is still to be answered conclusively. In an empirical analysis based on data from the German Socio‐Economic Panel and the International Adult Literacy Survey, a broad econometric strategy is applied to solve the problem of unobserved heterogeneity and reveal the mechanism underlying wage differences between matched and mismatched workers. Results show that wage differentials can be explained by a poor matching in the labor market, rejecting the hypothesis that mismatched workers compensate for unobserved productivity differences.     

The UK National Minimum Wage's Impact on Productivity

Low pay poses issues for managers internationally. We examine productivity in low‐paying sectors in Britain, since the introduction of the National Minimum Wage (NMW). We use a multiple channel analytical strategy, emphasizing the wage incentives channel and linking it to a model of unobserved productivity. We estimate firm‐specific productivity measures and aggregate them to the level of low‐paying sectors. Difference‐in‐differences analysis illustrates that the NMW positively affected aggregate low‐paying sector productivity. These findings highlight increased wage incentive effects with implications for management practice and public policy since ‘living’ wages may be productivity enhancing.     

市场竞争与价格离散——影响机理与经验证据

价格离散背离了"一价定律",是市场运行效率低的一种反映,但却是一种普遍存在的现象。那么,通过市场竞争机制能否降低某一行业（产品）的市场中的价格离散?本文先是分别在消费者信息搜寻理论和厂商空间竞争理论的框架下,分析市场竞争对价格离散的影响机理。然后,本文收集了我国地级（及以上）城市的车险市场上所有企业的价格和其他相关变量,研究主要发现：即使去除了产品异质性,车险市场仍然存在明显的价格离散,企业之间价格的变异系数的均值和中位数分别为0.472和0.445;市场竞争能够降低车险市场的价格离散,平均而言,企业数目提高10家（市场集中程度降低一单位样本标准差）,企业之间车险价格的标准差将降低其平均水平的约25%（5%~6%）。辅助性分析和稳健性分析支持了本文结论。本文的政策含义在于：应当增进供给侧的竞争,降低需求侧的信息搜寻成本。