Complementarity Between Low- and High-Skilled Workers and the Employment Impact of Tax versus Human Capital Policies

The present paper analyses theoretically the impact of substitutability and complementarity between labour market segments on the efficiency of policies tackling low-skilled unemployment. Based on a search and matching model with multiple segments interacting through the production function, it is shown that the efficiency of cost policies - decreasing payroll taxes on low-skill segments - increases with the segments' substitutability. Reducing the relative cost of low-skill labour - through tax wedge decrease - induces labour demand increase if low-skill labour is substitute to other production factors. The efficiency of productivity policies - upgrading workers from lower to higher-skill segments - increases with their complementarity. Enhancing human capital allows increasing production - constrained by the scarcity of high-skill labour - hence increases low-skill labour demand if factors are complements. Consequently, variations of the efficiency of both policies may derive from the technological change, modifying the complementarity between segments.