Investment Under Uncertainty
(Princeton U. press, 1994) 
Avinash Dixit and Robert Pindyck

    Economics defines investment as the act of incurring an immediate cost in the
expectation of future rewards. Firms that construct plants and install equipment,
merchants who lay in a stock of goods for sale, and persons who spend time on
vocational education are all investors in this sense. Somewhat less obviously, a firm that
shuts down a loss-making plant is also "investing": the payments it must make to extract
itself from contractual commitments, including severance payments to labor, are the
initial expenditure, and the prospective reward is the reduction in future losses.