"When regressing the pseudo-descendant’s earnings on pseudo-ancestor’s earnings, the results are surprising: the long-run earnings elasticity is positive, statistically significant, and equals about 0.04. Stated differently, being the descendants of the Bernardi family (at the 90th percentile of earnings distribution in 1427) instead of the Grasso family (10th percentile of the same distribution) would entail a 5% increase in earnings among current taxpayers (after adjusting for age and gender)."
So if your family was rich then, you probably make 5% more than than most people now. Nothing much to see here.
I think the story might be more in the variance rather than the mean. Sure, those in the 90th percentile make only a little more, what about the 99.99th percentile? My guess is that the ultra elite still have huge amounts of wealth and the statistic was diluted with a large sample set.
Surnames are heritable through the male line only. Genes are heritable through both parents. Wealth is some societies is heritable mostly through the male line, and in other societies through both lines.
Assuming that in the ~584 odd years from the study to the present day that 20 generations passed (average of 30 years per generation), the specific great-great-grandparent who passed on that name has roughly a 0.5^30 on that person (which is an infinitesimally small number).
However, rich people usually marry rich people. It's likely these results aren't just direct inheritance, or direct genetics, but it shows stratification within Italian society.
* To get contracts regardless of ones qualifications. I've read that Aristocrats ensure their kids have ivy league degrees to maintain a illusion of fairness.
There's an article I read here on HN that says, Ivy league schools are successful because they select applicants who would be successful without them.
I would posit the other question, how could they not?
Propensity to lying, cheating, saving, nepotism, length of life, fecundity, access to healthcare, intelligence, math ability and so many more factors are easily inheritable.
Yeah. Even if they were genetically dispossessed to have higher IQs, better health and extreme motivation it should have been pretty genetically diluted after 600 years.
Assortative mating can help maintain or increase any endowment. Think of that as being a within-family/smaller-scale version of the existing genetic gradient by SES (eg "The Genetics of Success: How Single-Nucleotide Polymorphisms Associated With Educational Attainment Relate to Life-Course Development" https://www.gwern.net/docs/genetics/correlation/2016-belsky.... , Belsky et al 2016; "Genetic analysis of social-class mobility in five longitudinal studies" http://www.pnas.org/content/early/2018/07/03/1801238115 , Belsky et al 2018a.)
I'm so grateful for the parent commenter who looked at the VoxEU source, because it helped put things into perspective.
A 5% earning increase isn't too surprising, given that the land claims and other investments are still respected today. It's a bit like Fry's bank account on that early Futurama episode. Those 600 years were a battle between compounding interest and regional turmoil/uncertainty. It's pretty cool that the holdings still have a legacy while not stifling all social mobility.
averages/median Hide too much. Better question is What is the probability of being in the 90th percentile of wealth conditional upon your ancestors being in the 90th percentile of wealth and compare that against the bottom 10th percentile?
Edit: added ‘median’ for the ctrl-f keyboard warrior
So if your family was rich then, you probably make 5% more than than most people now. Nothing much to see here.