Researcher Elias Einiö found that a 10,000-euro increase in dormmates' parents earnings translated into a 2.6-percent hike in income between the ages of 28 and 42, if a conscript himself is from a family with above-median income.
That effect was evident but not as pronounced among conscripts whose parents earned less than the median annual salary, which was 31,930 euros in 2017.
Social stratification reinforced
This effect was only found among people whose families were higher-income to start with. Lower-income soldiers, on the other hand, were found to be more likely to pursue higher education if they were army colleagues with better-off recruits.
Their incomes, however, didn’t increase as much as those from higher-income families.
Einiö also found that better-off conscripts were more likely to work in the same companies as their friends from army days, suggesting that networks built during military service are important in future working life.
The study’s abstract says that the "findings imply that social stratification reinforces economic and educational inequality between rich and poor families".
Some 70 percent of Finnish men complete military service. Conscription is compulsory for male citizens, with exemptions granted for health reasons, if people fail the fitness tests or if conscripts opt for non-military service instead.
The army therefore serves as a giant melting pot for male Finnish society. At present Finnish conscripts are divided alphabetically into dorms. The result is pretty much the same as a random selection.
It's possible that the trends uncovered in this research might have practical implications with benefits for society.
"For example in the United States Air Force Academy there has been research into how students could be split into groups to maximise their performance," says Einiö.
Since 1995, women have been allowed to serve on a voluntary basis, with an average of 400-600 doing so annually.