So in America (or any nation) you will end up with a relatively average (native born) population, with disparities in earnings accounted for by the relative economic strength by historical accident of the racial/gender groups, who themselves are effectively in competition with the top 1% of foreign countries (since those are the only ones given the opportunity to migrate).
Thus you have the results seen above.
The first form of selection bias is inside your country. If you don't already have status and wealth, then you won't even be able to overcome the cognitive/emotional load that's required to leave your country.
The second form of selection bias is when the Immigration Officer says yes or no.
The first form of selection bias is far more effective at weeding out the "low" earners and ensuring the top earners are pre-selected for immigration.
There is a third form of selection bias but that may not help with this conversation, and that's geographical. Crossing an ocean has historically been seen as riskier then crossing land, so that weeds out the risk averse.
> The first form of selection bias is inside your country. If you don't already have status and wealth, then you won't even be able to overcome the cognitive/emotional load that's required to leave your country.
But what you said doesn't reflect reality. Many of those who migrate to the US (or equivalent developed country) are either through scholarships/grants or already have a job offer. They do not have any sort of cognitive/emotional load. I'm sure every country allows a greater portion of immigration for competent people (irrespective of their social standing or economic stability) as opposed to those who have wealth/status and not contribute back to their society.
> The second form of selection bias is when the Immigration Officer says yes or no.
How is this "selection bias" and how does it apply to the context of the article we are discussing?
> The first form of selection bias is far more effective at weeding out the "low" earners and ensuring the top earners are pre-selected for immigration.
Why would a "top earner" want to go to the US if he is already a "top earner"? This makes no sense.
> There is a third form of selection bias but that may not help with this conversation, and that's geographical. Crossing an ocean has historically been seen as riskier then crossing land, so that weeds out the risk averse.
I think you are confusing the term "selection bias" as applied to this article with issues faced during immigration.
My question has nothing to do with the problems one faces during immigration. It has more to do with those who have already immigrated and earning substantially more than the natives (according to the article about 117% more). My question is why this gap between the immigrated vs the natives with respect to median income.
Then on top of that, a person with money needs to have the entrepreneurial and pioneer spirit to leave their home country and go somewhere totally new. That isn't normal. Perhaps that isn't so much the case today, but in the mid 80s around the time my parents came here no one in their family were here and it was very rare to see someone from our racial background. Something about just leaving your home and taking a huge gamble in flying across the ocean in search of a better life, that seems to show the ability to dream of a better life and sacrifice in search of it, which is by no means common.
My dad told me that in leaving Sri Lanka, he took the student visa route which involved writing some exam (probably the GRE but I never got the specifics). Anyways, did terribly on the exam a few times and then kept paying to take it over. He also spent hundreds on application fees to foreign universities. He told me that during this time, a bunch of people from his village in Sri Lanka would be sitting around laughing at him for all his failures and wasted effort. I think what the shows is that the desire to emigrate was no only difficult but at the time was by no means normal. It wasn't everyone who was putting in the gargantuan effort to escape Sri Lanka (of course this was before the civil war got really bad so the situation likely changed as the 80s wore on.)
I think these factors also contribute to economic sucess.
If you are in India or China, you can not just board a plane to US. The best way to immigrate to US is to perform well in STEM education, then go to US for higher studies. Since it is difficult for them to get a US visa, most of the people who are able to go through the whole process are usually the top performers who work very hard.