When I first started out, I was a young mathematician at Manchester University who could have gone anywhere. Looking back as a professor of economics at the London Business School and director at the Centre for Economic Forecasting, I wouldn't change much of my professional life. I've been given opportunities beyond my wildest dreams, and so I've never regretted even a big decision at the time - leaving maths to those brighter than myself to study economics at London University.
My economics has helped me enjoy my professional life by enabling me to operate in the triumvirate of business, academia and government. However, although spells in business and a City consultancy enabled me to maintain a stimulating closeness to business, I regret allowing the management skills I do have to have been built up solely from experience. I could have benefited from the courses that many of today's business schools provide.
At a personal level, I regret that circumstances have forced me not to be close to my two sons as they grew up in Scotland; and that I did not meet my wife, Angela, until much later in my life. But the big change I would make would have been to learn to play my favourite instrument, the cello, when I was younger, rather than starting a few months ago.
As it is, I have to dream of Pablo Casals and try to play so that the cat doesn't flee the room.