In theory, such specialisation should increase the efficiency of the venture-capital process, as it does in other industries.

ECONOMIST: Money to burn

In theory, the PPP was meant to harness the efficiency of the private sector and, in return for healthy profits, transfer risks to the firms doing the work.

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The combination of cheap jets with greater fuel efficiency and a critical mass of these critters in the sky can, in theory, lower the price per seat considerably.

FORBES: Private Jet Boom

Mr Llewellyn also questions the theory that building-society conversions will herald a wave of takeovers, leading to efficiency gains as overcapacity is cut.

ECONOMIST: Building societies

In market theory the "selfishness" of the economic agent - in this case the GP practice - drives the efficiency of the system by forcing other economic agents to compete to provide the most efficient service.

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