Knowledge that Transforms

In many of the decisions we make we rely on the advice of others who have preceded us. For example, before we buy a car, choose a dentist, choose a spouse, find a school for our children, sign on to a retirement plan, etc. we usually ask the advice of others who have experience with such decisions. The same is true when we make major financial decisions. Here people easily take advice from their fellow workers or relatives as to how to choose stock, balance a portfolio, or save for their child’s education. Although some advice we get is from experts, most of the time we make our decisions relying only on the rather uninformed word-of-mouth advice we get from our friends or neighbors. We call this ?aive advice? In this paper I will outline a set of experimental results that indicate that word-of-mouth advice is a very powerful force in shaping the decisions that people make and tends to push those decisions in the direction of the predictions of the rational theory.

Inference methods that recognize the clustering of individual observations have been available for more than 25 years. Brent Moulton (1990) caught the attention of economists when he demonstrated the serious biases that can result in estimating the effects of aggregate explanatory variables on individual-specific response variables. The source of the downward bias in the usual ordinary least-squares (OLS) standard errors is the presence of an unobserved, state-level effect in the error term. More recently, John Pepper (2002) showed how accounting for multi-level clustering can have dramatic effects on t statistics. While adjusting for clustering is much more common than it was 10 years ago, inference methods robust to cluster correlation are not used routinely across all relevant settings. In this paper, I provide an overview of applications of cluster-sample methods, both to cluster samples and to panel data sets.

Using three major U.K. pension reforms as natural experiments we investigate the relationship between pension saving and discretionary private savings. Unlike most differences-in-differences approaches which rely on average differences between control and treatment group, we use economic theory to model the response of each individual household. The empirical analysis, based on the Family Expenditure Survey, uses both time-series and cross-sectional variation to identify the behavioral response. The earnings-related tier of the pension scheme is found to have a negative impact on private savings with relatively high substitution elasticities; the impact of the flat-rate tier is not significantly different from zero.

Economics departments face increasing pressure to improve the quality of undergraduate instruction (William E. Becker, 2000). A teachertraining program (TTP) is one strategy departments can use to improve the quality of teaching. A TTP typically targets graduatestudent teaching assistants (TA’s) but can also provide valuable education to new junior faculty. The task set for this paper is to describe the ideal TTP. What is ideal is a matter of opinion. Mine is based on long experience with the TTP at the University of North Carolina–Chapel Hill, on familiarity with TTP’s at the University of Nebraska–Lincoln, Indiana University, and Purdue University, and on my experience as director of teaching workshops sponsored by the AEA Committee on Economic Education (Salemi et al., 1996). I begin with principles that should guide creation of a TTP, describe a TTP’s essential elements, and conclude with a consideration of resource issues.

Productivity reflects not only how efficiently inputs are transformed into outputs, but also how well information is applied to resource allocation decisions. This paper examines how information technology has affected capacity utilization in the trucking industry. Estimates for 1997 indicate that advanced on-board computers (OBCs) have increased capacity utilization among adopting trucks by 13 percent. These increases are higher than for 1992, suggesting lags in the returns to adoption, and are highly skewed across hauls. The 1997 estimates imply that OBCs have enabled 3-percent higher capacity utilization in the industry, which translates to billions of dollars of annual benefits.

This paper introduces a new technique for testing the Heckscher-Ohlin model that allows for the possibility that countries with sufficiently disparate endowments specialize in unique subsets of goods. Results based upon industry-level data reject one-size-fits-all homogeneity in favor of Heckscher-Ohlin specialization. Results also reveal that industry-level data hide substantial intra-industry heterogeneity, violating the assumptions of the model and complicating the interpretation of results from earlier research. A methodology for adjusting industry output to reflect underlying product variation is introduced. Reestimation of the model using adjusted aggregates in place of standard industry classifications provides strong support for Heckscher-Ohlin specialization.

A new and easily implementable framework for the empirical analysis of the relationship between aggregate and individual wages is developed. Aggregate real wages are shown to contain three important bias terms: one associated with the dispersion of individual wages, a second deriving from compositional changes in the (selected) sample of workers, and a third reflecting the distribution of working hours. Their importance for interpreting the path of aggregate wages and of the returns to education for recent experience in Britain is highlighted. A close correspondence between the estimated biases and the patterns of differences shown by aggregate wages is established.

We study nearly 7,000 retirement accounts during the April 1994–August 1998 period. Several interesting patterns emerge. Most asset allocations are extreme (either 100 percent or zero percent in equities) and there is inertia in asset allocations. Equity allocations are higher for males, married investors, and for investors with higher earnings and more seniority on the job; equity allocations are lower for older investors. There is very limited portfolio reshuffling, in sharp contrast to discount brokerage accounts. Daily changes in equity allocations correlate only weakly with same-day equity returns and do not correlate with future equity returns.