Some say that 'value' may be quantified by the money paid by the requirer for the means of satisfaction. I'm less certain that we need bother with the term at all. Money certainly establishes the scale of one requirement relative to another, but it seems to me that its great merit is that makes needless a further multiplication of terms, to include value (for example).
This is useful since it is possible to focus on the requirements of the subject while excluding discussion of psychological states of valuation, which are, I suggest, not one state but either; a) the relative weight placed on, and effort directed towards satisfying, the requirement or; b) The state of calm and relaxation of effort succeeding the successful satisfaction of a requirement, in other words the absence of a). The great error is to think that b) causes a), which is obviously nonsense in my terms, or that both a) and b) are positive and that 'value' overall is the sum of these two elements, an error that results in an illusory discrepancy between the money metric and the apparent psychological state. The state of satisfaction is irrelevant; the relative strength of the requirement is all that one need consider.