Americans overestimate the size of smaller groups, underestimate the size of larger groups

Recent YouGov survey data shows Americans have a hard time estimating the population of a number of groups:

When people’s average perceptions of group sizes are compared to actual population estimates, an intriguing pattern emerges: Americans tend to vastly overestimate the size of minority groups. This holds for sexual minorities, including the proportion of gays and lesbians (estimate: 30%, true: 3%), bisexuals (estimate: 29%, true: 4%), and people who are transgender (estimate: 21%, true: 0.6%).

It also applies to religious minorities, such as Muslim Americans (estimate: 27%, true: 1%) and Jewish Americans (estimate: 30%, true: 2%). And we find the same sorts of overestimates for racial and ethnic minorities, such as Native Americans (estimate: 27%, true: 1%), Asian Americans (estimate: 29%, true: 6%), and Black Americans (estimate: 41%, true: 12%)…

A parallel pattern emerges when we look at estimates of majority groups: People tend to underestimate rather than overestimate their size relative to their actual share of the adult population. For instance, we find that people underestimate the proportion of American adults who are Christian (estimate: 58%, true: 70%) and the proportion who have at least a high school degree (estimate: 65%, true: 89%)…

Misperceptions of the size of minority groups have been identified in prior surveys, which observers have often attributed to social causes: fear of out-groups, lack of personal exposure, or portrayals in the media. Yet consistent with prior research, we find that the tendency to misestimate the size of demographic groups is actually one instance of a broader tendency to overestimate small proportions and underestimate large ones, regardless of the topic. 

I wonder how much this might be connected to a general sense of innumeracy. Big numbers can be difficult to understand and the United States has over 330,000,000 residents. Percentages and absolute numbers regarding certain groups are not always provided. I am more familiar with some of these percentages and numbers because my work requires it but it does not come up in all fields or settings.

Additionally, where would this information be taught or regularly shared? Civics classes alongside information about government structures and national history? Math classes as examples of relevant information? On television programs or in print materials? At political events or sports games? I would be interesting in making all of this more publicly visible so not just those who read the Statistical Abstract of the United States or have Census.gov as a top bookmark know this information.

Estimating the undercounts and overcounts of the 2020 Census

The decennial census is a big undertaking. And the work continues: the Census Bureau just released their estimates of how well the 2020 counts reflect the population of the United States.

Photo by Kaboompics .com on Pexels.com

“Today’s results show statistical evidence that the quality of the 2020 Census total population count is consistent with that of recent censuses. This is notable, given the unprecedented challenges of 2020,” said Director Robert L. Santos. “But the results also include some limitations — the 2020 Census undercounted many of the same population groups we have historically undercounted, and it overcounted others.”

The two analyses are from the Post-Enumeration Survey (PES) and Demographic Analysis Estimates (DA) and estimate how well the 2020 Census counted everyone in the nation and in certain demographic groups. They estimate the size of the U.S. population and then compare those estimates to the census counts…

The results show that the 2020 Census undercounted the Black or African American population, the American Indian or Alaska Native population living on a reservation, the Hispanic or Latino population, and people who reported being of Some Other Race.

On the other hand, the 2020 Census overcounted the Non-Hispanic White population and the Asian population. The Native Hawaiian or Other Pacific Islander population was neither overcounted nor undercounted according to the findings.

Among age groups, the 2020 Census undercounted children 0 to 17 years old, particularly young children 0 to 4 years old. Young children are persistently undercounted in the decennial census.

I can imagine how some might read this story: the Census uses estimates and additional data to make claims about what is supposed to be a comprehensive count? Here are some quick thoughts in response:

  1. The numbers might sound like a lot: an undercount of the total population of 18.8 million? Yet, the error rates for separate groups are reported often between 1-4% and the total is off less than 6%.
  2. If the official numbers are known to be overcounts or undercounts, how might researchers take that into account when using the data?
  3. The Census is using multiple data sources to try to both get the most accurate statistics and improve its methodology. Explaining this publicly hopefully helps builds trust in the process and the numbers.
  4. It will be interesting to see how all of this informs future data gathering efforts. If there are consistent undercounts with certain groups, what changes in the coming years? If other data sources provide useful information, such as vital records, can these be incorporated into the data? And so on.

Collecting data about the population of a large country is no easy task and is a work in progress.

Illinois lost residents 2010 to 2020; discrepancies in year to year estimates and decennial count

Illinois lost residents over the last decade. But, different Census estimates at different times created slightly different stories:

Photo by Nachelle Nocom on Pexels.com

Those estimates showed Illinois experiencing a net loss of 9,972 residents between 2013 and 2014; 22,194 residents between 2014 and 2015; 37,508 residents between 2015 and 2016; about 33,700 residents between 2016 and 2017; 45,116 between 2017 and 2018; 51,250 between 2018 and 2019; and 79,487 between 2019 and 2020…

On April 26, the U.S. Census Bureau released its state-by-state population numbers based on last year’s census. These are the numbers that determine congressional apportionment. Those numbers, released every 10 years, show a different picture for Illinois: a loss of about 18,000 residents since 2010.

What’s the deal? For starters, the two counting methods for estimated annual population and the 10-year census for apportionment are separate. Apples and oranges. Resident population numbers and apportionment population numbers are arrived at differently, with one set counting Illinois families who live overseas, including in the military, and one not.

Additionally, the every-10-years number is gathered not from those county-by-county metrics but from the census forms we fill out and from door-to-door contacts made by census workers on the ground.

The overall story is the same but this is a good reminder of how different methods can produce different results. Here are several key factors to keep in mind:

  1. The time period is different. One estimate comes every year, one comes every ten years. The yearly estimates are helpful because people like data. That does not necessarily mean the yearly estimates can be trusted as much as the other ones.
  2. The method in each version – yearly versus every ten years – is different. The decennial data involves more responses and requires more effort.
  3. The confidence in the two different kinds of estimates is different because of #2. The ten year estimates are more valid because they collect more data.

Theoretically, the year-to-year estimates could lead to a different story compared to the decennial estimates. Imagine year-to-year data that told of a slight increase in population while the ten-year numbers provided a slight decrease in population. This does not mean the process went wrong there or in the narrative where the yearly and ten-year estimates agreed. With estimates, researchers are trying their best to measure the full population patterns. But, there is some room for error.

That said, now that Illinois is known as one of the three states that lost population over the last decade, it will be interesting to see how politicians and business leaders respond. I can predict some of the responses already as different groups have practiced their talking points for years. Yet, the same old rhetoric may not be enough as these figures paint Illinois in a bad light when population growth is good in the United States.

States that are losing Congressional seats did not necessarily lose population

With new Census data, the United States House of Representatives is going through reapportionment. Here is the breakdown of who is gaining and losing seats:

This could be an easy narrative to follow with the absolute number of seats: there are winners and losers and there are patterns to which states are winning or losing (Sun Belt and West versus Midwest and Northeast). This would fit with a prevalent American narrative that growth is good and states with growing populations are rewarded with more political representation.

But, there is a more complicated story behind these numbers. States did not necessarily lose population to lose a House seat. They might have just grown more slowly than other states. The overall growth rate for the United States over the decade was 7.4%:

At a Monday press conference, census officials said the U.S. population increased to nearly 331.5 million, a 7.4% growth rate over the past decade and the second-slowest pace since 1790. The growth rate dropped from the previous decade of 9.7% between 2000 and 2010.

More details from the Census:

The state that gained the most numerically since the 2010 Census was Texas (up 3,999,944 to 29,145,505).

The fastest-growing state since the 2010 Census was Utah (up 18.4% to 3,271,616).

For nearly 2 million more residents, Texas gets two more seats. Utah’s population was up over 18% but get no more seats. The apportioning of seats is based on relative populations between states:

The distribution must be rejiggered after every census to account for expansion or shrinkage of each state relative to the others. Even states that grow in population may still lose seats if their growth is less robust than that of other states.

The case of New York is illustrative. Yes, it is interesting that is was 89 seats short of holding on to that House seat but it is also interesting that the state’s population increased.

Census officials said that New York had a “negative net domestic migration,” but that its population grew overall because of immigration.

Population loss is a tricky topic in the United States. No city or state wants to admit that people are leaving or that population losses outweigh gains. Similarly, few would want to address a loss of political power. All of this adds to the competition for residents where more people is seen as a plus and population loss or not enough population growth compared to others is seen as failure.

Homeownership up roughly 3% in 2020

After the housing crisis of the late 2000s, the homeownership rate in the United States declined to 62.9% in 2016 and then slowly inched up. But, it jumped quite a bit from 2019 to 2020:

During 2020, the homeownership rate jumped to roughly 67%, up nearly 3% from a year earlier after remaining largely flat for a decade, according to the Census Bureau.

The article attributes this jump to COVID-19 and the shift of people from cities to suburbs.

This may be true. I have chronicled this here on this blog. However, there is limited overall data compared to reports from various cities (like New York and San Francisco) or population figures for states and communities.

If indeed homeownership jumped nearly three percentage points in one year, this is a big shift. In the historical data table from the Census (Table 14), it is rare to find huge jumps year to year. The fallout from the late 2000s happened in relatively small decreases.

A big jump in 2020 has implications for multiple actors: communities with new residents and others losing residents; those involved in the housing industry from develoeprs to realtors to investors to landlords; residents as those with resources took advantage of purchasing opportunities while others struggled to hold on and payments are looming.

How will these dueling pressures – buying homes amid COVID-19 and low mortgage rates at the same time as economic uncertainty – play out?

US with lowest population growth over a decade in its history

New Census estimates suggest sluggish population growth in the United States between 2010 and 2019:

The new statistics permit an estimate of the U.S. population on Census Day (April 1, 2020) to have been 329.2 million people. If that turns out to be the case, the decade growth rate between 2010 and 2020 will be the lowest decade growth in U.S. history.

Figure 2 displays population growth rates for 10-year periods between the first U.S. census (taken in 1790) and projected results for the 2020 census (downloadable Table A). The projected growth of 6.6% between 2010 and 2020 is lower than in any previous decade, including the Great Depression years of the 1930s, when the nation registered 7.3% growth. It is roughly half the growth rate of the 1990s, a time of rising immigration and millennial-generation births.

The 2010s decade was one of fewer births, more deaths, and uneven immigration (downloadable Table C). Although immigration may have become unusually low due to recent federal restrictions that led to a decline in the noncitizen foreign-born population, low natural increase levels—fewer births, more deaths—will likely continue regardless of federal policy, as a result of the aging of the population. Some of this change can be attributed to lower fertility rates and the aging into adulthood of the last of the millennial population. However, census projections show older populations—especially those over age 65—will continue to display far higher rates of growth than youth.

In the United States, population growth is good. It implies status, expansion, success, new markets, getting bigger, being an attractive place for people from elsewhere to come. And without immigration, what would the population change be?

At this particular moment, I would guess that relatively few people are aware of such data. The Census Bureau continues to pump out information about communities and the country. The average resident may not need to be following such information. Is daily life significantly changed if the decade growth rate was 5% versus 8%? What are the effects of these different numbers on social life, politics, and the economy? Yet, in the broader view, these numbers might be more interesting.

I could imagine multiple ways leaders and the American public might take this data about growth. Is there an appetite for more population growth or an underlying assumption that America – and everything about it – will continue to grow at much higher rates? Is this slowdown in population growth taken as a sign of decline or indicative of multiple social issues? Perhaps other concerns are far more important today that basic demographics. And I suppose other might note that higher percentage population growth requires a lot more people than it did historically when the United States was much smaller.

Census data on how Chicago would have lost more residents in the 2010s if not for international migration

I was looking at Census Bureau data recently on population change in metropolitan statistical areas from 2010 to 2019. Here is what I found about Chicago:

The data shows the Chicago MSA lost nearly 3,000 residents over the decade. This is something urbanists, demographers, and Chicago area leaders have been tracking and trying to explain.

The data above helps provides details on this population change. The net migration data shows the region gained nearly 200,000 residents via international migration. If you rank all of the MSAs over the decade, Chicago was #10 on the list of international migrants. Chicago continues to be an important center for immigrants (even as it lags behind New York, Miami, Los Angeles, Houston, Washington, Boston, Dallas, San Francisco, and Seattle).

This means that if the Chicago area had fewer international immigrants, it would have lost a lot more people. If international migration was more like San Diego or Tampa or Minneapolis, the region would have lost more than 50,000 people. While I suspect few in the Chicago region would like to lose any residents over a decade, the situation would be much worse without the city and region continuing to attract immigrants.

American population change by the second

In searching for housing data this week, I came across a small animated widget on the Census website:

I like this presentation for three reasons.

First, a static image does not do this graphic justice. The different bars, all four of them, moved in time with the passage of time. It is one thing to read that something happens every few seconds or minutes; it is another to see it count down or up next to other markers.

Second, while a larger presentation might help display the gravity of the population changes – imagine a map filling with new people – this is a pint-sized graphic with lots of information going into it. Population losses and gains can be complicated with lots of different inputs. This graphic boils it down to three major demographic factors: births, deaths, and immigration.

Third, this highlights the large American population and its growth. Given all the social, cultural, and political issues of recent years, I have wondered what role the size of the US population plays. Addressing any major issue might be more difficult given all of the people groups and experiences, regional differences, and more.

Of course, any graphic aims to simplify and this graphic does as well. At the same time, in a world awash in information, simple yet well-design presentations can go a long way to conveying helpful information.

Is the definition of suburbs really in doubt or are the suburbs simply multi-dimensional?

One writer suggests the definition of suburbs is unclear because the federal government does not offer an official definition:

The term has practically been rendered a semantic argument. Some have a location-based definition: that it’s a smaller community on the outskirts of a larger city, while others define it visually, by cul-de-sacs upon cul-de-sacs of similarly developed homes. Both could be correct, since there’s no existing federal definition for suburbia.

Existing HUD definitions of American areas include “urban” and “rural,” but there is no such “suburban” category.

A 2013 Harvard University study found that there is “no consensus to what exactly constitutes a suburb.” It added that suburbs have been defined over the years by any number of metrics from physical proximity to cities, to modes of transportation, to general appearance…

The Census Bureau and HUD are currently working toward building out proper definitions and statistical areas based on 2020 census data. 

As a scholar who studies suburbs, I find this conversation a little odd. Here is why.

The Census Bureau has tracked the suburban population for decades. For example, the 2002 publication “Demographic Trends in the 20th Century” clearly shows the growth of suburban populations.

https://www.census.gov/prod/2002pubs/censr-4.pdf

As this table suggests, within metropolitan areas there are central cities and suburbs. The area outside central cities and with enough connections to the city and metropolitan region (as delineated by counties) counts toward the suburban population.

On the other hand, the definition of suburbs is multi-faceted and incorporates location relative to a big city and density. But, it also includes the feel and experience of an area. This is where the boundaries are more blurred; you could have neighborhoods in big cities that are full of single-family homes and lots of driving or pockets of more dense rural areas with connections to big cities. There are also a variety of suburban communities ranging from bedroom suburbs to industrial suburbs to ethnoburbs to working-class communities to edge cities and more. The kinds of suburbs might differ but there are common features of suburban life that Americans like.

Across the multiple measures noted in this story, they coalesce around a similar range of Americans living in the suburbs, whether the Census Bureau is measuring or people are self-reporting: roughly 50-55% of Americans live in suburbs.

Complex suburbia might be hard to fully encompass and it has changed over time. However, it hangs together enough to differentiate from big cities and rural areas. A new definition from the Census might help establish geographic and conceptual boundaries but these are always in flux as communities and metropolitan areas change.

Census cutting short time going door to door

The Census Bureau will not be able to go door to door as long as planned and this could affect the quality of the data at the end:

building door entrance exit

Photo by Pixabay on Pexels.com

Attempts by the bureau’s workers to conduct in-person interviews for the census will end on Sept. 30 — not Oct. 31, the end date it indicated in April would be necessary to count every person living in the U.S. given major setbacks from the coronavirus pandemic. Three Census Bureau employees, who were informed of the plans during separate internal meetings Thursday, confirmed the new end date with NPR. All of the employees spoke on the condition of anonymity out of fear of losing their jobs…

Former Census Bureau Director John Thompson warns that with less time, the bureau would likely have to reduce the number of attempts door knockers would make to try to gather information in person. The agency may also have to rely more heavily on statistical methods to impute the data about people living in households they can’t reach.

“The end result would be [overrepresentation] for the White non-Hispanic population and greater undercounts for all other populations including the traditionally hard-to-count,” Thompson wrote in written testimony for a Wednesday hearing on the census before the House Oversight and Reform Committee…

Moving up the end date from Oct. 31 for door knocking is likely to throw the census, already upended by months of delays, deeper into turmoil as hundreds of thousands of the bureau’s door knockers try to figure out how to conduct in-person interviews as many states grapple with growing coronavirus outbreaks in the middle of hurricane season.

Beyond the political football that the Census can be, Census data is important for researchers, residents, and political leaders. Not being able to go through the full data process and having to impute more data means that more of the final counts will need to be estimated. Since the decennial Census tries to get data from every household in the United States, it has some of the most comprehensive data. Lower counts, less time, COVID-19, political wrangling – may this not disturb useful and important data results.