The effectiveness of job creation tax credits

We estimate the causal effects of job creation tax credits on employment using the exogenous spatial and time variations in the value of the credits across Georgia's 159 counties over a 15-year period. We employ three empirical approaches: regression discontinuity design models making use of the sharp discontinuity in eligibility for credits of different value; difference-in-differences models using inter temporal and inter and intra-county changes in credit value; and employment differences in bordering census tracts that qualify for different valued credits. We obtain mixed results, but in general they provide little evidence for the proposition that job creation tax credits create additional employment.