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Estimating unauthorized immigrant population

Estimating the number of unauthorized immigrants in the US using the residual method and various surveys

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Jan 18, 2026
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How many illegal immigrants came into one US during President Biden administration

There is no single, uncontested tally of how many people “came into” the United States illegally during the Biden administration because agencies and analysts report different metrics (encounters, got...

Feb 3, 2026

How do researchers estimate the number of undocumented immigrants using the ACS and CPS?

Researchers typically use a "residual" approach built on surveys — primarily the and the — that subtracts an independently estimated count of legally present immigrants from the total foreign‑born mea...