Immigration and labour-market outcomes in the United States: a political-economy puzzle

Based on a larger survey of the literature (Gaston and Nelson,2000), this paper argues: (i) that econometric research uniformlyfinds very small labour-market effects of immigration; (ii)that labour and trade economists have differed in their interpretationof this finding; and (iii) that this difference is driven exclusivelyby different dimensionality assumptions (with labour economistspreferring a 1-sector x m-factor model and trade economistsan n-sector x m-factor model). It is then argued that the tradeeconomists' model, along with its presumption of factor-priceinsensitivity to immigration is the more useful as a presumptiongenerator. The paper concludes with a discussion of the political-economyimplications of these results.