Some of this century's many valuable contributions to economics, like macroeconomics, econometrics, and game theory, are widely recognized. However, arguably equally important is the enhanced role of empirical study permitted by more abundant data and improved methods. Also insufficiently recognized are the increased rigor and use of applied economics in public finance, regulation, corporation finance, etc., employing abstract theory and sophisticated data analysis. The striking contrast with earlier intuitively based applied economics and empirical study is illustrated. Comparison with Marshall's Principles also indicates that, except for macroeconomics, remarkably little space in today's texts deals with some ofthe rich contributions ofthis century.

1. The modified Linder Theorem, 630. — 2. The role of the income effect, 631. —3. Concluding comment, 632.

I. The Greek audience, 366. — II. Financing the Greek festival, 370. — III. The magnitude of the financial burden, 373. — IV. Concluding comment: Relevance for contemporary urban planning, 375.

I. The double (stock-flow) equilibrium condition, 46. — II. On the Patinkin dichotomization argument, 47. — III. … And liquidity preference vs. loanable funds, 49. — Appendix: The excess demand for stocks, 53.

Introduction, 545. — I. A simple model, 545. — II. Some consequences of the analysis, 549. — III. The simple model and reality, 552.

I. Introduction, 439.—II. Least-cost number of firms in a multiproduct industry, 441.—III. Shape of the M locus: economic interpretation, 446.—IV. Regions in which some specified number of firms may be optimal, 450.—V. Scale of demand and cost-minimizing market form, 454.—VI. The single-product case, 455.—VII. Conclusion, 460.—Appendix A: Proof of Theorem Ib, 462.—Appendix B: Proof of Theorem 3, 464.

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.

I. The problem, 547. — II. Cost of capital: whose opportunity cost? 548. — III. A few formal relationships, 549. — IV. A diagrammatic approach to cost of capital, 552. — V. Transactions costs and taxes in practice, 555. — VI. A few comments on the opportunity loci, 559. — VII. Characteristics of an optimal financial structure, 561. — VIII. The real marginal cost of debt and equity, 564. — IX. A measure of the cost of capital, 567. — X. Capital as a weighted average, 569. — XI. Conclusion, 571. — Appendix A, 571. — Appendix B, 575.

I. Introduction, 48. — II. A preliminary model for the valuation of convertible bonds, 49. — III. Statistical implementation of the model, 51. — IV. Altering the assumptions, 54. — V. Summary comment, 59.