I am grateful to my hon. Friend for being so generous in giving way early in his speech. He may intend to address this issue later, but will he comment on some of the difficulties involved in measuring the effects of different programmes? We discussed and received evidence about those problems in Committee. The prisoner scheme in Peterborough is a perfect, text-book example of payment by results, but the proposition for a youth club is completely different because of the different client group, control group, time period and the different influences on people’s lives.