The Earnings of Skilled and Unskilled Immigrants at the End of the Nineteenth Century
利用19世纪末爱荷华州约4000名工资收入者的样本，区分了熟练与非熟练移民在劳动力市场上的不同经历，发现熟练移民有初始收入优势，但非熟练移民通过工作经验逐渐缩小了部分差距。
Most historical studies of immigration in nineteenth-century America have failed to distinguish among the labor-market experiences of different immigrant groups. Using a sample of some 4000 wage earners from turn-of-the-century Iowa, we examine the relative earnings of skilled and unskilled immigrants and suggest the factors which contributed to their very different post-immigration experiences. The results indicate that prior knowledge of a trade conferred upon immigrants an initial earnings advantage, but that unskilled immigrants managed subsequently to close some but not all of the gap by reaping greater returns to experience on the job.