Market proxies and the conditional prediction of returns

Ex post efficient proxies for the market portfolio are tested against the equal weight proxy. The equal weight proxy outperforms the others when the criterion is squared error of conditional prediction of returns. The ex post efficient proxies use maximum likelihood estimates of return. Stein estimates of return will generally be different from the maximum likelihood estimates and they necessarily correspond to market proxies which are not efficient ex post. In other words, there generally exists a better, inefficient, proxy than an ex post efficient proxy when the criterion is squared error of conditional prediction of return.     

CMEA experience in multinational forecasting of science and technology advance

The effort begun six years ago to develop procedures for integrating technological forecasting activities of the CMEA member states is described. It is felt that such joint undertaking has a positive effect on all participants.     

Components of effective devaluation and the domestic rate of inflation: The case of Israel

Developing countries have frequently resorted to effective devaluation by changing either their formal rate of exchange, or by using non-formal components, such as taxes and subsidies. The ensuing increase in the domestic price of imports has inflationary effects. This paper analyses the Israeli experience to investigate the inflationary effects of increases in import prices and alternative methods of devaluation. It is found that formal and non-formal devaluation appear to have the same long-run effects on the price level, but are not the same in timing: A formal devaluation leads more quickly to increases in domestic prices.     

A model of market-making with imperfect information

Although the prevention of false markets is one of the major concerns of stock market authorities in the UK and elsewhere, until recently, the theoretical literature on the workings of markets with imperfect information has been sparse. This paper analyses the problem of providing liquidity to investors when price-sensitive information is unequally distributed. Specifically we shall model the activities of a market-maker when certain traders have price-sensitive information unavailable to other market participants. Our model will show how the bid-asked spread would be determined in such a market. It is useful in explaining certain tactics employed by stock market traders and in suggesting alternative ways of evaluating market efficiency. The theory is developed in three sections: (1) the determination of the bid-asked spread for a single, isolated transaction; (2) the determination of the bid-asked spread in a continuous market; (3) the relationship between the spread and the size of transaction.