Russel-Research-Method-in-Anthropology

288 Chapter 10
population. Many surveys are conducted again and again to monitor changes
and to ensure against picking a bad sample. Multiple cross-sectional polls use
a longitudinal design. The daily—even hourly—tracking polls in U.S. presidential
elections are an extreme example, but in many industrialized countries
some questions have been asked of representative samples for many years.
The Gallup Poll, for example, has been asking Americans to list ‘‘the most
important problem facing this country today’’ for about 60 years. The data
track the concerns of Americans about unemployment, the quality of education,
drugs, street crime, the federal deficit, taxes, health care costs, poverty,
racism, AIDS, abortion. . . . There are not many surprises in the data. People
in the United States are more worried about the economy in recessions, less
worried when the economy is clicking along. Only about 10% said that the
war in Iraq was the most important problem in America in March 2004, a year
after the invasion, but the number jumped to 26% in April and stayed there
for a year. The data from the Gallup Poll, and others like it, are important
because they were collected with the same instrument. People were asked the
same question again and again over the years. After several generations of
effort, longitudinal survey data have become a treasured resource in the highly
industrialized nations.
Panel Studies
Multiple cross-sectional surveys have their own problems. If the results
from two successive samples are very different, you don’t know if it’s because
people’s attitudes or reported behaviors have changed, or the two samples are
very different, or both. To deal with this problem, survey researchers use the
powerful panel design. In a panel study, you interview the same people again
and again. Panel studies are like true experiments: Randomly selected participants
are tracked for their exposure or lack of exposure to a series of interventions
in the real world.
The Panel Study on Income Dynamics, for example, has tracked about
8,000 American families since 1969. Some families have been tracked for 36
years now, and new families are added as others drop out of the panel (families
are interviewed every other year). Among many other things, the data
track the effect of living in different kinds of neighborhoods on the social and
economic mobility of men and women, of Whites and African Americans, of
old people and young. The PSID is run by the Institute for Social Research at
the University of Michigan, which also makes the data available to the public
at http://psidonline.isr.umich.edu/. Hundreds of papers have been written from
the data of this study. (To find papers based on the data from this panel study,
look up PSID as a keyword in the electronic databases at your library.)