METROPOLITAN HOUSE PRICES IN SOUTH AFRICA: DO THEY CONVERGE?

The question this paper investigates is whether or not different metropolitan areas each constitute a separate housing market or whether or not there is a single South African housing market. Theory on the Law of One Price suggests that if products or geographic areas belong in the same market, their absolute prices must converge, so that their relative prices are stationary. By using cross-sectional time series data of five metropolitan areas, the paper tests for the Law of One Price by applying the Im, Pesaran and Shin panel unit root test. The paper finds strong evidence of convergence in large middle-segment house prices and weaker support for convergence in medium middle-segment house prices. In addition, the paper finds no evidence for convergence in small middle-segment house prices. This suggests the existence of a national market for large and possibly middle-segment houses in metropolitan areas, but separate metropolitan markets for small middle-segment houses. In addition, the paper estimates the speed of convergence and finds that large middle-segment house prices converge within two to seven quarters, while the speed of convergence for medium middle-segment house prices in three of the five areas is five to eight quarters.     

Competition Policy: What are the Costs and Benefits of Measuring its Costs and Benefits?

Summary  Competition authorities are increasingly measuring the effects of their enforcement actions, seeking a robust justification for the proliferation of competition policy. We highlight the importance of identifying the right counterfactual against which to measure effects, and set out the relevant categories of costs and benefits. We then explore how a balance can be struck between the benefits and inherent limitations of these measurement exercises. Relatively crude analyses of cartel action benefits can be sufficient to achieve public legitimacy for competition policy. Assessing the effects of merger and conduct inquiries is often ambiguous, but could be used to improve decision-making processes. Director and Managing Consultant, respectively, at Oxera, Oxford and London. The valuable comments of Fod Barnes, Kerry Hughes and an anonymous referee are gratefully acknowledged. The opinions expressed in this article are those of the authors alone.     

Risk Sharing in a World with Processing Costs: Trading versus Banking

We analyze the bank versus exchange problem in a Diamond Dybvig (1983) economy with exogenous transaction processing costs. We find that processing costs in the market enables the bank to overcome the side trade threat ( Jacklin (1987) ) and offer some desirable liquidity insurance. Moreover, in the bank equilibrium processing costs are proportional to consumption, while in the market economy early and late consumers incur equal costs. These two effects explain that for a given level of aggregate processing costs, the bank economy is superior. On the other hand, the number of transactions in the bank economy is larger. It is for this reason that if processing costs are proportional to transaction value, and independent of the mechanism used, the exchange economy is superior.     

Accounting Policies in Agencies with Moral Hazard and Renegotiation

We emphasize the role of accounting policies, and their audit, in an earnings management setting. We use a two–period agency in which three frictions interact: the agent privately observes action (or effort) supply and output, and the initial contract is subject to renegotiation. This creates a setting in which both players' behavior is of concern, and, importantly, information rationing is efficient. Moreover, this information rationing is directly interpretable as being produced by an accounting policy whose application is ensured by an auditor.     

Foreign Factor Ownership and Optimal Tariffs

In the presence of foreign factor ownership tariffs change not only the terms of (goods) trade but also income flows between countries. Assume that only the home country owns factors abroad. Then the optimal tariff is negative if and only if foreign factor ownership entails trade-pattern reversals. Trade-pattern reversals are neither a necessary nor a sufficient condition for a negative optimal tariff if the foreign country owns factors in the home country. Changes in the home country's tariff shift the foreign country's offer curve. This adds a new dimension to optimal tariff analysis.     

On optimal investiment strategies

Suppose an investor has a fixed decision horizon and an appropriate utility function for measuring his or her utility of wealth. If there are only two investment vehicles, a risky and a risk-free asset, then the optimal investment strategy is such that, at any time, the amount invested in the risky asset must be the product of his or her “current risk tolerance” and the risk premium on the risky asset, divided by the square of the diffusion coefficient of the risky asset. In the case of more than one risky asset, the optimal investment strategy is similar, with the ratios of the amounts invested in the different risky assets being constant over time.     

Saving Accounts versus Stocks and Bonds in Household Portfolio Allocation

We study the structure of household portfolios of financial wealth by analyzing both the determinants of total financial wealth and the choice between risky (stocks and bonds) and riskfree assets (saving accounts). The econometric specification is a generalized trivariate Tobit model, estimated on a cross section of 3,077 households in the Netherlands in 1988. We account for endogeneity of financial wealth and for selectivity due to nonreporting. Results show that the level of financial wealth and the marginal tax rate are major determinants of the allocation between riskfree and risky assets.