In neoclassical economics, the value of an object is nothing more than the price it brings in an open and competitive market which in general is primarily determined by the demand for the object relative to supply.
i think what you are referring to is the difference between the economic value and market value. If a consumer (i.e., an NFL team) is willing to buy a good (or use a draft pick on a player) at a price higher than the market value, it implies that the consumer places a higher economic value then the market price. You believe the market value for Allen was a 5. Perhaps the rams agree with your assessment given the statement by alllen, but were willing to pay more for him due to a perceived demand among the other teams thus increasing his economic value.
