by Tony Mastria, MPA '15

How much of your surroundings are shaped by traits that no longer exist? Does the design and character of a city persist when the features around which it was built have long since disappeared?

The answer may surprise you.

In her ongoing research with co-author Byron Lutz, Trachtenberg School of Public Policy and Public Administration Professor Leah Brooks is analyzing the “long-term effects of land use choices”—that is, how long-ago choices about development patterns shape the present.

“In particular we are studying whether the pattern of Los Angeles streetcars—which had their heyday in the 1910s and were entirely extinct by the early 1960s—are still visible in land use patterns today,” Professor Brooks explained.

“The short answer is yes,” she said. “There is a very visible relationship between modern density—density both of people and buildings—and the location of now-extinct streetcars. We find evidence that this persistence in land use patterns is due to persistence in zoning designations. This suggests that initial decisions about land use regulations are very consequential.”

This phenomenon traces all the way back to the initial decision to build infrastructure in certain places and ways. Even if the original construction goes away (like the streetcars in L.A.), major changes to transit costs are insufficient to yield major changes in land use patterns.

The implications of Brooks’ research are not limited to Los Angeles or streetcars, and it’s not difficult to imagine how similar scenarios of development may have occurred in other metro areas throughout the country. (It may even have happened in your own neighborhood, whose growth could have been helped by some long-lost architectural “ancestor”.)

Even more enduring than the regulatory effects she studies is Brooks’ passion for her research. “I’ve been interested in cities for a very long time,” she said, “probably since I was an undergraduate.”

“I study why cities do what they do,” she said. “Why are they formed the way they are? What makes urban development persist and why? What organizations make for healthy neighborhoods and why? How do forms of government change outcomes in urban areas?”

In another study probing the depths of these questions, Brooks and her co-author Gisela Rua are currently analyzing “the effect of containerization—the major change to worldwide trade of putting goods into big boxes and shipping them around the world—on cities, both across and within cities.”

Professor Brooks is asking “Does containerization shift jobs across cities?” and “Does it change neighborhoods near and far from ports?” She hopes the answers will be of interest to economists, policymakers, businesses and average citizens.

So the next time you spot a container ship in the harbor, remember that it’s not just carrying khaki pants, flat-screen TVs, and Happy Meal toys—it’s also delivering a boatload of important research.

Before joining the Trachtenberg School, Professor Brooks was an economist for the Federal Reserve Board of Governors. Her work has been published in the Journal of Public Economics, the American Economic Journal, and the National Tax Journal, among others.

Today, Professor Brooks teaches Econometrics for Policy Research II to doctoral students at the Trachtenberg School, while dedicating her research to cities and what makes our urban areas look and function the way they do.