Buyer search and price dispersion: a laboratory study

We study markets with costly buyer search in which sellers simultaneously post prices. Buyers costlessly observe one or (with probability 1−q) two of the posted prices, and can accept one or pay to search again. The experiment varies q, the search cost, and the number of buyers. Equilibrium theory predicts a unified very low (high) price for q=0 (q=1) and predicts specific distributions of dispersed prices for q=1/3 and 2/3. Actual prices conform closely to the predictions in some treatments. Buyers’ reservation prices are biased away from the extremes, however, and sellers’ prices have positive autocorrelation and cross-sectional correlation.     

Firm Size Distribution and Growth*

Abstract Empirical documentation of the sectoral distribution of firm size for a set of European countries reveals substantial differences. We study the relationship between productivity growth at the industry level and size structure. A positive and robust relation is found between average firm size and growth. We ask why size should matter for growth by considering the role of innovation to construct a test based on the differential effect of size on growth according to various indicators of R&D intensity. Our results indicate that larger size fosters productivity growth because it allows firms to take advantage of all the increasing returns associated with R&D. We argue that our test can be interpreted as a test of reverse causality, which lends support to the view that firm size has a causal impact on growth.     

Elastic demand, sunk costs and the Kreps–Scheinkman extension of the Cournot model

Summary. The paper shows that, with any rationing mechanism between the efficient and proportional extremes, the Kreps-Scheinkman two-stage quantity-price game reduces to the Cournot model if demand is uniformly elastic and if all costs are sunk at the first stage, thus providing positive results to set against existing negative statements. Received: May 24, 1995; revised version: March 6, 1997     

Bayesian exploratory factor analysis

This paper develops and applies a Bayesian approach to Exploratory Factor Analysis that improves on ad hoc classical approaches. Our framework relies on dedicated factor models and simultaneously determines the number of factors, the allocation of each measurement to a unique factor, and the corresponding factor loadings. Classical identification criteria are applied and integrated into our Bayesian procedure to generate models that are stable and clearly interpretable. A Monte Carlo study confirms the validity of the approach. The method is used to produce interpretable low dimensional aggregates from a high dimensional set of psychological measurements.     

Strategic spin-offs of input divisions

When a downstream producer enters backward into the input market, a “helping the rivals effect” exists: Such entry hurts the firm's downstream business as it increases upstream competition and thus benefits its rival downstream firms. This negative externality prevents the newly-created upstream unit from expanding. A spin-off enables the firm to credibly expand in the input market, thereby forcing its upstream competitors to behave less aggressively. Spin-offs occur in equilibrium if and only if the number of downstream firms exceeds a threshold level. When there is more than one integrated firm, a spin-off by a firm can trigger spin-offs by others that would not occur otherwise.     

Bundling as an optimal selling mechanism for a multiple-good monopolist

Multiple objects may be sold by posting a schedule consisting of one price for each possible bundle and permitting the buyer to select the price-bundle pair of his choice. We identify conditions that must be satisfied by any price schedule that maximizes revenue within the class of all such schedules. We then provide conditions under which a price schedule maximizes expected revenue within the class of all incentive compatible and individually rational mechanisms in the n-object case. We use these results to characterize environments, mainly distributions of valuations, where bundling is the optimal mechanism in the two and three good cases.     

Do Spillovers Stimulate Incremental or Drastic Product Innovations? Evidence from German Establishment Data*

Despite the generally recognized importance of knowledge spillovers, the empirical literature is essentially silent on the type of innovation stimulated by spillovers. We estimate the determinants of product innovations differing in their degree of newness to the adopting firm. Knowledge spillovers from rivals have a positive impact on incremental innovations. This impact is largely independent of participation in R&D cooperation. Spillovers exert no such independent influence on drastic innovation activities. The results support the hypothesis that establishments face difficulties in using knowledge that comes from areas they are not familiar with. Establishments exploit spillovers for incremental innovations rather than for drastic innovations. To some degree R&D cooperation can help to overcome the difficulties in using spillovers for drastic innovations. Furthermore, our estimates provide evidence that the firm's own R&D effort and the use of outside information are substitutes.     

Modelling Electricity Prices: International Evidence*

This article analyses the evolution of electricity prices in deregulated markets. We present a general class of models that simultaneously takes into account several factors: seasonality, mean reversion, GARCH behaviour and time‐dependent jumps. The models are applied to daily equilibrium spot prices of eight electricity markets. Eight different nested models were estimated to compare the relative importance of each factor in each of the eight markets. We find strong evidence that electricity equilibrium prices are mean‐reverting, with volatility clustering (GARCH) and with jumps of time‐dependent intensity, even after adjusting for seasonality.     

Heuristic learning and the discovery of specialization and exchange

I develop and calibrate an agent-based model of boundedly rational, adaptive agents in a two-good production and exchange economy to replicate human-subject outcomes in the same eight-person experimental economy. To test agents’ ability to capture human behavior, I extend the model and use its output to make predictions about a second experimental environment in which the group of eight agents is slowly constructed by merging smaller groups. This environment improves human-subject performance in the specialization and exchange task, and commensurate improvement emerges for some parameterizations of the agent-based model. This iterative process yields incremental improvement of decision-level theories about economic discovery.     

The distributive and welfare effects of product and labour market deregulation

This paper studies the effects of product and labour market deregulation on wage inequality and welfare. By constructing an analytically tractable model in which the level of product market competition and the wages are endogenously distributed among sectors, I show that deregulation in goods market has mixed effects on inequality: the wage variance and the Gini index are lower, but the ratio of the highest over the lowest wage paid in the economy increases. Moreover, deregulation in labour markets raises the aggregate level of employment and the average real wage but reduces the welfare of trade unions in sectors with a low level of competition.