I think that the main issue is that it tries to come up with a metric that works across every country which is basically pointless because a lot of them are failed states where income information isn't reliable or meaningful.
So they come up with stuff like "how high is teenage pregnancy" and "what is the male female work balance" which they define as being proxies for social mobility I assume because if you have five kids at age 20 and you're forced to stay at home then you have none.
The problem is that it just introduces a billion ways to influence the actual rankings, they are value judgements.
If you look at well functioning countries only, then you can pretty much look at how many people in the bottom decile of parental household income end up in the top decile of household income.
You still have the issue though that this only tells you how the distribution actually ends up, not how it _could_ look in a specific country if everyone actually tried their hardest to climb the social/financial ladder.
I think that the main issue is that it tries to come up with a metric that works across every country which is basically pointless because a lot of them are failed states where income information isn't reliable or meaningful.
So they come up with stuff like "how high is teenage pregnancy" and "what is the male female work balance" which they define as being proxies for social mobility I assume because if you have five kids at age 20 and you're forced to stay at home then you have none.
The problem is that it just introduces a billion ways to influence the actual rankings, they are value judgements.
If you look at well functioning countries only, then you can pretty much look at how many people in the bottom decile of parental household income end up in the top decile of household income.
You still have the issue though that this only tells you how the distribution actually ends up, not how it _could_ look in a specific country if everyone actually tried their hardest to climb the social/financial ladder.