Limited Computational Ability and Social Security

We revisit the role of social security in countering inadequate saving for retirement. We compute the optimal social security tax rate for households who lack the computational ability to solve dynamic optimization problems. Instead, they follow the simple rule of thumb of consuming and saving a fixed fraction of disposable income. This departs from the tradition of computing the optimal tax rate when households suffer from some type of behavioral bias yet possess the ability to solve dynamic optimization problems. Our general equilibrium model is calibrated to the moments of the distribution of saving rates in the US, and our results are generally supportive of a social security program as large as the one in the US