UNEMPLOYMENT AND THE PRODUCTIVITY SLOWDOWN: AN EFFCIENCY WAGE PERSPECTIVE

Many OECD economies suffered a productivity slowdown beginning in the early 1970s. However, the increase in unemployment that followed this slowdown was more pronounced in European economies relative to the USA. In this paper we present an efficiency wage model, which enables us to identify two basic channels through which the productivity slowdown can affect workers' effort incentives. Predictions of the model are consistent with the different trends in unemployment across countries over this period in the face of a similar slowdown in productivity. We also demonstrate how the link between growth and unemployment depends upon labour market institutions in such a way that we can reconcile the mixed empirical results observed in the literature.     

The World Price of Covariance Risk

In a financially integrated global market, the conditionally expected return on a portfolio of securities from a particular country is determined by the country's world risk exposure. This paper measures the conditional risk of 17 countries. The reward per unit of risk is the world price of covariance risk. Although the tests provide evidence on the conditional mean variance efficiency of the benchmark portfolio, the results show that countries' risk exposures help explain differences in performance. Evidence is also presented which indicates that these risk exposures change through time and that the world price of covariance risk is not constant.     

S&P 100 Index Option Volatility

Using transaction data on the S&P 100 index options, we study the effect of valuation simplifications that are commonplace in previous research on the timeseries properties of implied market volatility. Using an American-style algorithm that accounts for the discrete nature of the dividends on the S&P 100 index, we find that spurious negative serial correlation in implied volatility changes is induced by nonsimultaneously observing the option price and the index level. Negative serial correlation is also induced by a bid/ask price effect if a single option is used to estimate implied volatility. In addition, we find that these same effects induce spurious (and unreasonable) negative cross-correlations between the changes in call and put implied volatility.