Most Americans think U.S. has more immigrants and a lot more Muslims than it really has

Many Americans list immigration as one of the nation's biggest concerns, especially when it comes to the 2016 presidential election. But a 2015 survey by global market research company Ipsos found that most Americans think the immigrant population is much higher than it actually is, Ana Swanson reports for The Washington Post. "On average, surveyed Americans guessed that one-third of people in their country are immigrants," when the actual figure is 14 percent. When asked about the size of the Muslim population, the average guess was 15 percent, but the actual Muslim population is 1 percent.

Ipsos said in a statement: "The biggest over-estimations tend to be in countries with very low levels of immigration, such as Argentina, Brazil, South Africa, India, Mexico and Peru, all of which overstate the proportion of immigrants by over 20 percentage points, but Canada and the USA, countries with higher levels of immigration, are also among the most inaccurate. Saudi Arabia and to a lesser extent Israel are the only countries that underestimate the proportion of immigrants." (Ipsos graphic: Respondents from countries above the line guessed too high on the immigrant population in their country)

In a more recent Ipsos survey, from last month, 49 percent of Americans said they worry that immigrants have made it more difficult to get jobs. That number is up from 46 percent in October 2015, but down from 60 percent in 2011. Also, 77 percent of Americans believe terrorists are pretending to be refugees who will enter the U.S. to cause violence and destruction.

There are some positives. When asked if they think immigrants play a positive role in society, 35 percent of respondents said yes, up from 18 percent in 2011. Also, 36 percent said immigration is good for the economy, up from 23 percent in 2011.