Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We show that a two‐tier pension system, with a pay‐as‐you‐go first tier and a fully funded, defined wage‐indexed second tier, can provide for optimal intergenerational risk‐sharing without distorting the labour supply, thereby achieving the first best. Other arrangements with a fully‐funded second tier fail to achieve the first best.