That is a new paper by Matthew T. Gregg, forthcoming in Journal of Development Economics. Here is the abstract:
This paper explores some long-standing questions of the legacy of American Indian boarding schools by comparing contemporary Indian reservations that experienced differing impacts in the past from boarding schools. Combining recent reservation-level census data and school enrollment data from 1911 to 1932, I find that reservations that sent a larger share of students to off-reservation boarding schools have higher high school graduation rates, higher per capita income, lower poverty rates, a greater proportion of exclusively English speakers, and smaller family sizes. These results are supported when distance to the nearest off-reservation boarding school that subsequently closed is used as an instrument for the proportion of past boarding school students. I conclude with a discussion of the possible reasons for this link.
And this is from the paper’s conclusion:
Last, the link drawn here between higher boarding school share and assimilation should not be misinterpreted as an endorsement of coercive assimilation. Unobserved costs generated by the first generation of students might outweigh the estimated gains in long term assimilation. The program itself was extremely costly, which is one of the reasons for the change in policy towards on-reservation schooling during the 1930s. These results do, however, suggest that the assimilation gains from boarding schools are sizable, but, due to data limitations, this study does not reflect a complete assessment of the trade-offs of boarding school attendance.