This chapter reviews inference about large autoregressive or moving average roots in univariate time series, and structural change in multivariate time series regression. The "problem" of unit roots is cast more broadly as determining the order of integration of a series; estimation, inference,...

Ever since the pioneering work of Jan Tinbergen, econometric modelers have been aware of the danger that their models can be unstable over time and across policy environments. Work over the past fifteen years has produced a set of statistical procedures for identifying and modeling structural...

This paper studies the possibility of using the broad monetary aggregate M2 to target the quarterly rate of growth of nominal GDP. Our findings indicate that the Federal Reserve could probably guide M2 in a way that reduces not only the long-term average rate of inflation but also the variance...

Proposed changes in the U.S. Social Security provisions include increasing the normal retirement age from 65 to 67 and changing from 3% to 8% the increase in benefits for each year that retirement is delayed after normal retirement. The paper considers the interaction between these changes and...

The paper develops a model of retirement based on the option value of continuing to work. Continuing to work maintains the option of retiring on more advantageous terms later. The model is used to estimate the effects on retirement of firm pension plan provisions. Typical defined benefit pension...

Empirical analysis often raises questions of approximation to underlying individual behavior. Closer approximation may require more complex statistical specifications, On the other hand, more complex specifications may presume computational facility that is beyond the grasp of most real people...

This paper investigates the possibility, raised by Perron (1989, 1990a), that aggregate economic time series can be characterized as being stationary around broken trend lines. Unlike Perron, we treat the break date as unknown a priori. Asymptotic distributions are developed for recursive,...

U.S. farms, and with them agricultural lending institutions, are currently experiencing their most severe stress since the 1930s. As international trade in farm products has expanded, so has the sensitivity of farm incomes to fluctuations in domestic and world economic conditions. Thus, while...