[We present a model of information acquisition in a competitive market in which traders can learn both from costly (and diverse) private enquiry and price, which costlessly (but partially) reveals the total amount of information known to all traders. Our major purpose is to show that an equilibrium exists in such a market: that is, there exists a rational expectations competitive equilibrium in which the amount of costly diverse information each trader acquires is endogenously determined. From this result we investigate the change in the informativeness of price relative to changes in the level of noise, the cost of acquiring information, and the distribution of traders' risk preferences.]

TRADITIONAL ECONOMIC ANALYSIS of the theory of the firm has concentrated on single-product firms. But, in reality, most businesses produce many products, and many regulatory and antitrust issues involve only these enterprises. In recent years, economists and policymakers dealing with antitrust and regulatory issues have increasingly recognized the need for a theory that can be used to evaluate the efficiency of market structures in industries dominated by a few firms operating in a diverse range of markets. For such firms, conventional concepts of structure and performance such as economies of scale, measures of concentration, and barriers to entry do not adequately capture the complexity of market relationships. A few examples illustrate the complexities introduced by the multi-product firm and highlight the need for a theory that can be used to evaluate performance and conduct in its markets. In many trucking and air city-pair markets, the efficient number of carriers appears to be relatively small (perhaps even one). Does this imply, however, that trucking firms and air carriers that compete in a wide range of city-pair markets should be regulated as natural monopolists or that mergers involving overlapping markets should be disallowed? In the petroleum industry, there is a current trend to diversify into other sources of fuel, and in cable TV markets there are numerous attempts to integrate vertically. What should economists look for in evaluating whether these changes in market structure are motivated by efficiency or by anticompetitive behavior? For a dominant firm, such as AT&T, there is a frequent complaint that the incumbent firm is preventing entry by cross-subsidizing one of its products, which faces competition by entrants, at the expense of other of its products. What kinds of regulatory intervention in pricing or in market structure must be considered

A SSUMPTIONS regarding the depreciation ,AX rate for housing play an important role in the urban economics literature.1 The notion that houses filter down from higher to lower quality is prevalent in both academic and policy discussions of the nature of urban problems. Yet there has been no attempt to specify which depreciation rates are appropriate to these discussions, and little empirical investigation of depreciation in housing. This paper presents estimates of depreciation rates for housing which are appropriate to consideration of the filtering hypothesis. Estimates of these depreciation rates must be pursued differently from estimates of the depreciation rates for the aggregate capital stock of housing. A brief review of previous studies, which points out some of the difficulties which confound observation of depreciation rates, is presented in section I. Section II discusses specification, and section III describes the data and estimation technique used. Results are presented in section IV. Section V is a brief conclusion.

Robert E. Hamilton, William F. Wright, Internal Control Judgments and Effects of Experience: Replications and Extensions, Journal of Accounting Research, Vol. 20, No. 2, Part II (Autumn, 1982), pp. 756-765

Robert J. Swieringa, Karl E. Weick, An Assessment of Laboratory Experiments in Accounting, Journal of Accounting Research, Vol. 20, Supplement: Studies on Current Research Methodologies in Accounting: A Critical Evaluation (1982), pp. 56-101

Fewings [5] and Myers and Turnbull [13] have arrived at diametrically conflicting conclusions regarding the effect of growth on risk as measured by beta, the relative systematic risk in the Sharpe-Lintner-Mossin (SLM) capital asset pricing model. Fewings states his result in an unequivocal way: “…systematic capitalization risk of common stocks is undoubtedly a positive function of the rate of growth of expected corporate earnings” ([5, p. 53]) Myers and Turnbull, on the other hand, state their result in a more conditional form, making the result depend on the nature of market expectations revisions but conclude that “increasing the growth rate decreases B …” ([13], P. 327).

Clifford A. Ball, Adrian E. Tschoegl, The Decision to Establish a Foreign Bank Branch or Subsidiary: An Application of Binary Classification Procedures, The Journal of Financial and Quantitative Analysis, Vol. 17, No. 3 (Sep., 1982), pp. 411-424