Employing a panel data set that combines Statistics Korea’s ‘Mining and
Manufacturing Survey 2004-2008’ with ‘Current State of the National Trade
Union Organizations 2006-2008’, we examine impacts of unions on the
establishment’s employment size, wages and productivity. We use fixed-effects
methods to overcome limitations of previous research that relies on
cross-sectional data. We find that unions in small establishments with less
than 30 employees have little impact on the establishment’s employment size,
wages and productivity. Effects of unions on establishments with at least 30
employees differ by the measure of the performance. In particular, unions
raise the average wage of the establishment with at least 100 employees by
2.1% to 12.1%.