This paper studies three different measures of monthly stock market volatility: the time-series volatility of daily market returns within the month; the cross-sectional volatility or 'dispersion' of daily returns on industry portfolios, relative to the market, within the month; and the...

In a model where a variable Y[sub t] is proportional to the present value, with constant discount rate, of expected future values of a variable y[sub t] the "spread" S[sub t]= Y[sub t] - [theta sub t] will be stationary for some [theta] whether or not y[sub t]must be differenced to induce...

The permanent income hypothesis implies that people save because they rationally expect their labor income to decline; they save "for a rainy day". It follows that saving should be at least as good a predictor of declines in labor income as any other forecast that can be constructed from publicly...

In the presence of overlapping generations, markets are incomplete because it is impossible to engage in risksharing trades with the unborn. In such an environment the government can use a social security system, with contingent taxes and benefits, to improve risksharing across generations. An...