What Census Takers Can Learn From Birdwatchers

On a South Australian beach, researchers placed thousands of fake terns. Arranging the birds in colonies of 460 to 1020, the scientists orchestrated a count…actually two counts. One would come from drone images and the other from birdwatchers. The goal was to see which was more accurate.

The winner was the drones.

When people counted the birds in the drone snaps, the results were 43% to 96% more accurate than what the birdwatchers reported. Because drones are increasingly used to gather data like whale populations in the Pacific and orangutans in Nepal, their accuracy matters. But we do have a second issue. Eagles have been observed attacking drones and bear populations have responded with heart attacks.

So, there is more behind a bird census than just counting. How you do it affects accuracy and the well being of the population you are measuring.

And that takes us to the 2020 decennial census.

The 2020 Census

We’ve been measuring the U.S. population every 10 years since 1790. Mandated by the Constitution, its basic purpose is allocating seats in the House of Representatives. However, we could say that the census is also an economic document. It costs the Congress money and provides data that tells where to spend money.

Cost

It is expensive to count more than 325 million people who live in 126 million households (2016). In 2000, the census cost close to $8 billion while in 2010, it was in the vicinity of $14 billion. Covering a 12-year life cycle, estimates for the 2020 census have ranged from $12 billion to more than $15 billion.

You can see that cost soars in 2020:

Spending

Whereas the stated goal for the 2020 decennial census is population and housing data, that is only the beginning. From there federal agencies can determine how an estimated $675 billion will be allocated. They just need the data to identify their target communities.

HUD for example uses income and housing information for its assistance programs. One source of that information is the ACS (American Community Survey). But the ACS is an offshoot of the decennial. Published annually, the ACS gets its “sampling frame” from the decennial.

There are countless examples of how the decennial data are used. Federal, state and local governments use the data to make spending decisions about education, highways, Medicaid..the list is unending. Meanwhile, even small businesses can decide where to locate and invest. They can get handy demographic information on customers and even where low income concentrations might get them preferential tax treatment.

Our Bottom Line: Accuracy

The big worry for the 2020 census takers is accuracy. Looking back at 2010, they tell us that they undercounted renters, the black population, Hispanics and children under five years old.

Looking ahead, they cite the following problems:

So, returning to our Australian fake terns, we just need to remember that how you collect the data matters for accuracy and well being.

My sources and more: My top recommendation is this Wired article on the bird watchers. But if you want to learn more about the decennial, the possibilities include articles from Brookings here and here. You also might go to the Congressional Research Service and of course, census.gov, here and here.