Elaine Maag (Urban Institute) has published Tax Credits, the Minimum Wage, and Inflation (Jan. 2007) on the Urban-Brookings Tax Policy Center web site.  Here is the abstract:

Two primary wage-support policies help low-income families: the minimum wage and targeted tax credits. Since 1997, when Congress last raised the minimum wage, the real value of the minimum wage has fallen about 20 percent because of inflation, while the earned income tax credit (EITC) and child credit have been expanded. This brief illustrates how current tax rules interact with the minimum wage and considers whether increased tax credits could substitute for minimum-wage increases for those earning the federal minimum wage. The analysis shows that increasing tax credits enough to substitute for raising the minimum wage is probably infeasible because of both the cost and the high marginal tax rates required. A more direct route to helping low-wage workers is to raise the minimum wage and index it to inflation.