Counting Illegal Immigration

Submitted by Jerome L. Himmelstein on Thursday, 2/3/2011, at 6:13 PM

THE HANDOUT BELOW GOES WITH THE NEW YORK TIMES ARTICLE I HANDED OUT IN CLASS ON FEBRUARY 3 AND SUMMARIZES WHAT I SAID IN CLASS ABOUT THE ARTICLE.

 

COUNTING ILLEGAL IMMIGRANTS

 

Mellon 16, 2011

Professor Himmelstein

 

The Story

 

            The New York Times reports (2/1/11) that according to a report from the Pew Hispanic Center, there were 11.2 million illegal immigrants living in the U.S. in 2010, about the same as 2009, but down from a peak of 12 million in 2007.

            The article cites how the authors of the study interpret their findings:  stepped up enforcement along the border and stepped up deportations aren’t working.   Neither is  the policy of “attrition through enforcement,” as exemplified in Arizona’s recent laws—making life so difficult for illegals that they choose to go home.

            Immigration being a politically contentious issue, the NYT provides balance by citing supporters of the attrition policy, who argue that the Obama Administration’s decision to end high-profile raids in workplaces might explain the continuing high level of illegal immigrants.

 

A Measurement Problem

 

            But wait a second!   How do you measure the number of illegals in the U.S.?  This is not something that people would readily admit to a survey. 

            One of the things I want you to learn to ask when confronted with any number in the media is to ask automatically “how did they measure that?” and to be aware whether the media address that issue at all.   In this case, the NYT article does not.

            So, how do we answer the question?

            You might look at the Pew Report itself.   On p. 25, they discuss their methodology, which they call the “residual method”:   The researchers compared data from the Department of Homeland Security on the numbers of foreign-born persons in the U.S. legally to the number telling the Census Bureau’s Current Population Survey that they are foreign-born.   They subtract the first from the second, adjust for deaths and outmigration, and end up with an estimate of undocumented immigrants.

            What is also clear from the report and related articles is that researchers recognize that measuring undocumented immigrants is a dicey proposition and thus spend a lot of time working on the problem.

            You might also enlist Carl Bialik, the Numbers Guy at the Wall Street Journal.  In his  May 7, 2010 column he discusses the problems of counting illegal immigrants.   He points out that several studies come up with similar estimates, give or take a million.  However, all use some version of the residual method. One problem with this method, Bialik points out, is that we have no good data on how many undocumented immigrants choose not to respond to surveys or choose to lie about their place of birth.   Another problem is that there are no good estimates of outmigration.

            Higher estimates of 20 million undocumented immigrants rely on the volume of remittances sent back home and on the number of housing permits in enclaves with high numbers of illegal immigrants, both of which are even more problematic indicators.

 

Taking Notes