ÍøÆØÃÅ

Andrew Oswald appears to think that his proposal to conduct controlled experiments on working life and happiness is a novel one ("Give all your staff a real bonus - a No-Work Wednesday", THES , December 19/26).

Such experiments have been conducted for decades. Controlled experiments in organisational analysis have less capacity than one might expect to yield usable knowledge, although they continue to be conducted.

Christopher Grey Wolfson College, Cambridge