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 uniformly finds very small labour-market effects of immigration; (ii) that labour and trade economists have differed in their interpretation of this finding; and (iii) that this difference is driven exclusively by different dimensionality assumptions (with labour economists preferring a 1-sector x m-factor model and trade economists an n-sector x m-factor model). It is then argued that the trade economists' model, along with its presumption of factor-price insensitivity to immigration is the more useful as a presumption generator. The paper concludes with a discussion of the political-economy implications of these results. Copyright 2000 by Oxford University Press.