Acknowledgments
This guide was developed in conjunction with the Economics Tutorial Program at Harvard University, with support and assistance from The Harvard Writing Project. Nancy Sommers, Sosland Director of Expository Writing, proposed the idea in 1999, and I was asked to write the guide, which has since been distributed to the sophomores in the department each year. Kerry Walk, then Assistant Director of the Writing Project, saw the project through from inception to completion, commented on drafts, gave advice at every stage, and ultimately added the section on āFormatting and documentationā (Chapter 5). Christopher Foote, then Assistant Professor of Economics and Director of Undergraduate Studies, wrote part of Chapter 4, and Mireille Jacobson made substantial contributions to the section on āWriting economicallyā (Chapter 1), and she compiled the original appendices. Oliver Hart, Michael Murray, Lorenzo Isla, Tuan Min Li, Allison Morantz, and Stephen Weinberg also gave very helpful comments. Rajiv Shankar updated the appendices and prepared the manuscript for printing. Special thanks to Anita Mortimer, with regrets for her recent passing.
Introduction: The economic approach
LIST OF SUB-TOPICS Economics and the problem of scarcity The assumption of rationality Types of writing assignments |
Economists study everything from money and prices to child rearing and the environment. They analyze small-scale decision-making and large-scale international policy-making. They compile data about the past and make predictions about the future. Many economic ideas have currency in everyday life, cropping up in newspapers, magazines, and policy debates. The amount you pay every month to finance a car or new home purchase will depend on interest rates. Business people make investment plans based on expectations of future demand, and policy-makers devise budgets to achieve a desired macroeconomic equilibrium.
While the range of topics that interest economists is vast, there is a unique approach to knowledge, something common to the way all economists see the world. Economists share certain assumptions about how the economy works, and they use standard methods for analyzing data and communicating their ideas. The purpose of this guide is to help you to think and write like an economist.
ECONOMICS AND THE PROBLEM OF SCARCITY
Since its beginnings as āthe dismal science,ā economics has been preoccupied with the problem of scarcity. The hours in a day, the money in oneās pocket, the food the earth can supply are all limited; spending resources on one activity necessarily comes at the expense of some other, foregone opportunity. Scarcity provides economics with its central problem: how to make choices in the context of constraint.
Accordingly, economists ask questions such as: How does a consumer choose a bundle of commodities, given her income and prices? How does a country choose to meet its objectives, given its national budget? How do decision-makers allocate scarce resources among alternative activities with different uses?
While this central economic problem may be rather narrow, the range of topics that interest economists is vast. Indeed, insofar as it can be characterized as choice under constraint, any kind of behavior falls within the scope of economic analysis. As Lord Lionel Robbins (1984), one of the great economists of the twentieth century, put it:
It should come as no surprise that economists are sometimes called āimperialistsā by other social scientists for their encroachment on fields that traditionally belong to other disciplines. For instance, historians studying the migration patterns of eighteenth-century European peasants have explained the movement out of the countryside and into the cities in terms of broad social and cultural factors: the peasants were subjects of changing times, swept along by the force of history. By contrast, economists, such as Samuel L. Popkin (1979), have attributed urban migration patterns to the trade-offs faced and choices made by individual agents; from this perspective, the peasantsā behavior was rational.
THE ASSUMPTION OF RATIONALITY
Economists approach a wide range of topics with the assumption that the behavior under investigation is best understood as if it were rational (though we know that not all behavior is, in fact, rational) and that the best explanations, models, and theories we construct take rationality as the norm. Rationality, in the words of Frank Hahn, is the āweak causal propositionā that sets all economic analyses in motion. āEconomics can be distinguished from other social sciences by the belief that most (all?) behavior can be explained by assuming that agents have stable, well-defined preferences and make rational choices consistent with those preferencesā (Colin Camerer and Richard Thaler, 1995).
Rationality, in the standard sense of the economist, means that agents prefer more of what they want to less. This may seem like a rather strong proposition, insofar as it seems to imply that human behavior is ne...