War, Coal, and Forced Labor: Assessing the Impact of Prisoner-of-War Employment on Coal Mine Productivity in World War I Germany
研究一战德国煤矿中战俘对劳动生产率的影响，发现战俘就业导致煤矿生产率下降36%，其生产率仅为普通矿工的32%，暴力并非有效激励。
This paper assesses the causal relationship between POW assignments and labor productivity for a vital sector of the German World War I economy, namely coal mining. Prisoners of war (POWs) provided significant labor. Combining data on all Ruhr mines with a treatment-effects approach, I find that POW employment alone accounted for 36 percent of the average POW-employing mine’s annual productivity decline over wartime. Estimates also suggest that the representative POW’s productivity averaged 32 percent of the representative regular miner’s productivity and that POWs’ contribution to wartime coal output amounted to 3.9 percent. Violence did not serve as a powerful work incentive.