Intermediate 
Our new international survey across 33 countries shows how wrong people around the world are about key social realities.
British people think the top 1% wealthiest households own 59% of their countrys wealth, when they actually only own 23%. Americans think that 33% of their population are immigrants, when in fact it is only 14%.
Brazilians think the average age in their country is 56, when it is only 31. Russians think that 31% of their politicians are women, when it is only 14%.
In Britain, people think that 43% of young adults aged 25-34 still live at home with their parents, rather than the actual 14%. In India, the online population think 60% of the whole country also has internet access, when in fact only 19% do.
Why are people across the world so often clueless about these realities?
It is partly that we just struggle with basic maths and some of us clearly misunderstand the questions or interpret them differently. For example, most countries hugely overestimate how many people are not religious: across the 33 countries, respondents think that 37% are not religious but the average is actually just 18%. This is because we are thinking of how many people practise their religion, rather than how many people see themselves as having a religion.
People also take mental shortcuts, where they take easily available information even if it doesnt quite  t the question. Our huge overestimates of the rural populations in most countries will be affected by how large rural areas are, rather than a careful calculation of how many people live in them. In Daniel Kahnemans terms, answers to these sorts of questions are classic examples of fast thinking, rather than slow.
We see things from our own perspective and struggle to imagine the variety in our countries. This was highlighted by our Indian respondents who massively overestimated their populations access to the internet. Our study was mostly carried out through an online survey  and, in developing countries, this will be representative of a more wealthy, connected group rather than the general population. What we  nd throughout the study is that people generalize from their own situations and forget how unrepresentative they are.
We suffer from what social psychologists call emotional innumeracy when we are estimating realities: this means we are sending a message about what is worrying us as much as trying to get the right answers.
For Britain, worries are part of the explanation for peoples huge overestimates of how much the wealthiest own, how many young people are still living at home and what proportion of the population are immigrants (the guess is 25%, when it is really only 13%). People are worried about these things and, because of this, they overestimate how big the problems are.
But, the survey suggests there are also some issues where people are not as worried as they should be. For example, most countries hugely underestimate how much of their population is overweight or obese. The worst case is Saudi Arabia, where people think only 28% are, when 71% are. Britons think it is 44% when it is actually nearly half as much again  62% are either overweight or obese.
And, in many ways, it is not our misperceptions but these realities across different countries that are the most interesting and important aspects of the study. The top 1% in Russia own 70% of the nations wealth while the top 1% in New Zealand only own 18%. Half of Italians aged 25-34 still live with their parents, when it is only 4% in Norway. The average age in India is 27; it is 47 in Japan. Only 10% of politicians are women in Brazil, Hungary and Japan, when 44% are in Sweden.
When the reality is so strange and varied, it is no wonder were so wrong.