If all types of labor have the same elasticity of substitution with capital (i.e. β = γ = θ)
and the supply of all types of labor is fixed, then the burden of the corporate tax across skill-level
will be constant. If, however, the capital-skill complementarity hypothesis is correct and
β > γ > θ, then the ratio of high-skill wages to middle-skill wages increases with capital and the
ratio of middle-skill wages to low-skill wages increases with capital. These results are derived in
Appendix A.
3. Empirical Set-Up and Data
In order to test empirically the impact of openness on the incidence of corporate taxation,
we must first determine the variables that affect the gross wage of an individual. In a simple
model, we expect that both individual characteristics (I) and country characteristics (C) impact
individual wages. In the specification below, gross wage represents the mean annual gross wage
of individuals of skill-level (s) in a given country (j) and year (t).
ln(grosswagejts)=α+βIjts+γCjt+εjts (4)
Education level is the primary individual characteristic of interest. Mincer (1984)
develops the standard human capital earnings function; he formulates that an individual’s wage
is a function of years of schooling, experience, and experience squared. This formulation has
been empirically tested many times resulting in positive coefficients on years of schooling and
experience and a negative coefficient on experience squared.5 Gender is also likely to affect
wages and is often included as an independent variable. However, gender is often combined with
labor supply considerations because women’s labor supply often varies over time.6
The country characteristics of interest include the corporate tax rate, openness and the
interaction of the corporate tax rate with openness. I also include GDP per capita to control for
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