What is it worth?

Next month Radio 4 will run a series of programmes about pay and in preparation they have this bafflingly simplistic survey online: http://www.bbc.co.uk/radio4/features/pay/

My background is in sociology and this survey makes my jaw ache. How can one say what a profession 'should earn' in a total vacuum? Is that a Personal Assistant in London or somewhere much cheaper to live? A Retail Cashier at Tesco or an independent shop? Does the income of the Premiership Footballer include all their sponsorship deals? The 'should' is presented as simply a comparison exercise with the other professions and yet we aren't given the option of ranking them in terms of mental, personal or physical effort or effects of the work, difficulty of access to the profession, impact on other people's lives or livelihoods... The comparison is presented in such a way that seems to imply that some jobs may deserve a salary as low as £10k - a salary that can scarcely be lived on in this country much less in London, much less without recourse to benefits & tax credits. Are we expected to think of the Train Driver etc. as a lone individual and not take into account the fact that most people also have families to support, or may want a mortgage - something unattainable on the average income in this country?

I dread to think what generalisations the programme makers intend to arrive at when they examine the completely inadequate results that can be got from a survey like this one.