The Effects of Delays on the Stability and Rate of Convergence to Equilibrium of Oligopolies*

The stability of oligopolies is investigated using the Cournot strategy and a general output adjustment procedure. Information delays are incorporated in the adjustment procedure and their specific effects upon the dynamic stability of oligopolies is investigated. The stability of equilibrium for discrete models is unaffected by information delays and remoteness of planning horizons; however the rate of convergence to equilibrium may be slowed. For continuous models with delays, some restraints are required for stability.     

THE UK ECONOMY: ANALYSIS AND PROSPECTS

In this section of the review, Oxford Economic Forecasting providesan analysis of the current economic climate in the UK and abroadas well as setting out the main features of its latest forecast.In Section II the UK forecast up to 1988 is described. In SectionIII, following the theme of this issue, we analyse the effectsof changes in trend productivity growth on the UK economy.     

A New Look at the Monday Effect

It is well documented that expected stock returns vary with the day-of-the-week (the Monday or weekend effect). In this article we show that the well-known Monday effect occurs primarily in the last two weeks (fourth and fifth weeks) of the month. In addition, the mean Monday return of the first three weeks of the month is not significantly different from zero. This result holds for most of the subperiods during the 1962–1993 sampling period and for various stock return indexes. The monthly effect reported by Ariel (1987) and Lakonishok and Smidt (1988) cannot fully explain this phenomenon.     

MARKET STRUCTURE, PROGRAM DIVERSITY, AND RADIO AUDIENCE SIZE

This paper examines the relationships among radio station listenership, the number of program formats, and the number of stations. These relationships are statistically significant and consistent with theory, but the interrelationships are numerically small. The results imply that proposals by the federal Communications Commission and Congress to relax ownership restrictions must induce substantial changes in station numbers in order to noticeably increase programming diversity. Merely modest changes in these numbers will have only small diversity effects. The paper's results also imply that merely mandating the number of formats in a market may not be in the interests of listeners.     

SENSITIVITY ANALYSIS IN BENEFIT COST ANALYSIS: A KEY TO INCREASED USE AND ACCEPTANCE

"We must insist that all empirical studies offer convincing evidence of inferential sturdiness."
Sensitivit     

The Nation's Private Wealth -Some New Calculations for Australia*

This paper has two related purposes. The first is to bring together and review a number of earlier studies which have attempted to estimate the value of Australia's privately held wealth stock. The second is to present new estimates covering the 1980s. based partly on these earlier studies, which value all major components of the nation's private wealth at their market value, or a close approximation. The calculations reported here represent the first aggregate Australian wealth series for which comprehensive market valuation can be claimed. Australia's aggregate non-human private wealth was found to be $794 billion at 30 June 1985. The series as a whole suggests that previous estimates have significantly under-valued Australia's wealth. At 30 June 1981 the Helliwell-Boxall (1978) study. updated by the Reserve Bank, reported a value of $294.7 billion, while Williams (1983) gave a value of $360.5 billion. The corresponding estimate for the new series is $532.5 billion. Because the new calculations presented here value wealth by component. it is possible to identify omissions and valuation differences which account for most of the variation between these estimates.     

Efficient Funds in a Financial Market with Options: a New Irrelevance Proposition

Under the same assumptions that Ross used to assert the existence of an efficient fund (on which a spanning set of options can be written) we prove that almost any portfolio is an efficient fund. From a constructive point of view, a randomly chosen vector of portfolio weights yields an efficient fund. When the Ross assumptions are relaxed, a limited notion of efficiency-maximal efficiency-is the best attainable. The maximally efficient funds are also everywhere dense in the portfolio space. Some implications are discussed and illustrative examples given.