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Selected publication

Absolute income mobility and the effect of parent generation inequality: An extended decomposition approach
Liss, E., Korpi, M., & Wennberg, K.
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Publications

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  • Publications

Selected publication

No evidence of counteracting policy effects on European solar power invention and diffusion
Grafström, J., & Poudineh, R.
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About

  • About us

    • About
    • Contact us

  • Media

    • News archive

  • Cooperations

    • Eli F. Heckscher Lectures

Research

  • Areas

    • Labour Market Research
    • Competitiveness Research
    • Climate and Environmental Research

  • Ongoing research

    • Working Paper Series
  • People

    • Publications

    • Publications

      • Publications

    Working paper No. 219. Migration and Increasing Wage Inequality

    PublicationWorking paper
    Arbetsmarknad, Inkomstfördelning, Martin Korpi, Migration
    mk_migration_and_increasing_wage_inequality__can_imperfect_competition_explain_the_link__ratio_wp_219
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    Abstract

    In this paper, we test two hypotheses as regarding potential effects of domestic and international migration on wage inequality. One related to the possibility of wage competition, and another alternative hypothesis related to fixed set-up costs and indivisibilities for different types of industries within the local labour market. Using detailed information on Swedish local labour markets, derived from Swedish full population data, for 1993 and 2003, a panel model of percent changes in inequality is estimated. Thereby controlling for local level fixed effects as well as other competing explanations, the results suggest that positive net migration may affect income dispersion regardless of possible negative wage competition.

    Korpi, M. (2013). Migration and Increasing Wage Inequality: Can Imperfect Competition Explain the Link? Ratio Working paper No. 219.

    Details

    Author

    Korpi, M

    Publication year

    2013

    Similar content

    City size, employer concentration, and wage income inequality
    Working paperPublication
    Halvarsson, D., & Korpi, M.
    Publication year

    2025

    Published in

    Institute for Evaluation of Labour Market and Education Policy (IFAU)

    Abstract

    This study investigates the relationship between the urban wage premium and employer concentration using Swedish full population employer-employee data. Departing from an AKM modeling framework to distinguish worker from firm specific heterogeneity – a measure of rent-sharing – we then measure the urban wage premium using differences in the estimated firm fixed effects at the level of local industries, nested within local labor markets. Our results suggest that labor market employer concentration, as calculated using the Hirschman-Herfindahl index and a leave-one-out instrumental variable design, can account for a significant share of the estimated urban wage premium (UWP). Addressing city-level wage income inequality by applying our model to different segments of the local labor market income distribution, we find that while the UWP pertains to all income segments, it is largest for top-income levels (above the 90th percentile), and within this segment employer concentration also has the largest explanatory power. Thus, while being an important explanatory factor for all percentiles of the local income distribution, a relatively lower employer concentration within larger cities, and vice versa, higher concentration within smaller cities, primarily help explain the variance of top wages within these cities/labor markets.

    Ratio Working Paper No 363: City Size, Employer Concentration, and Wage Income Inequality
    Working paperPublication
    Korpi, M., & Halvarsson, D.
    Download
    Publication year

    2023

    Published in

    Rati Working Paper Series.

    Abstract

    In this paper, we build upon a monopsony framework, suggested by Card et. al. 2016, which links firm level productivity and rent-sharing to wage inequality. Specifically, our research questions address i) to which extent labor market concentration across firms (within different types of locally situated industries) affects variation in wages among workers within these firms and industries, and ii) how this variation in turn spills over into economy-wide inequality (measured at the level of local labor markets). Using linked employer-employee full population data for Sweden, and an AKM modelling framework to separate between worker- and firm-level heterogeneity, our results suggest that higher firm-level fixed effects (a measure of rent-sharing) is associated with lower labor market employer concentration, something which affects average wage income among firms accordingly. Addressing wage income inequality by applying our model to different segments of the local labor market income distribution, we find that reduced average employer concentration in larger cities accounts for almost all variation in the (positive) link between city size-and wage inequality, except for the largest metropolises where it captures around 30-50 percent of variation depending on the income segment that we focus on.

    Ratio Working Paper No. 358: Native Population Turnover & Emerging Segregation: The Role of Amenities, Crime and Housing
    Working paperPublication
    Korpi, M., Halvarsson, D., Öner, Ö., A.V. Clark, W., Mihaescu, O., Östh, J. & Bäckman, O.
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    Publication year

    2022

    Published in

    Ratio Working Paper.

    Abstract

    Using geo-coded full-population grid-level data for the three largest metropolitan areas in Sweden, 1993-2016, this paper i) estimates the level and pace of ethnic segregation, ii) examines possible tipping points in this development, and iii) gauges the importance of several mitigating or exacerbating factors (such as the mix of housing area tenure type, different types of amenities, and crime). We use OLS and 2SLS to estimate outcomes at two different geographic levels; 250 x 250 square meter grids and SAMS areas (roughly equivalent to US census tracts), respectively. On average, we find that for every 1 percentage point increase in immigration, native growth is reduced by around -0.3 percentage points. Crime levels exacerbate developments and factors such as housing area tenure-type mix and access to various amenities slows it down, but only marginally so. Using repeated and single random sampling for cross-validation, and the twin common methodological approaches as suggested in the literature, we estimate possible tipping points in these segregation developments. In contrast to most other studies in the literature, none of our potential tipping points are however statistically significant when probing their relevance in explaining factual population developments, suggesting a rather more continuous – albeit steeply so – segregation process rather than a structural brake. In terms of tipping point methodology, our main findings are that fixed-point estimation is less robust than R-square maximization for small geographical units, and that the former consistently selects for lower tipping-point candidates than the latter.

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