common trends the government s budget constraint and revenue smoothing abstract the requirement that the government s budget be balanced in present value terms is shown to be equivalent to the condition that government expenditures inclusive of interest tax receipts and seignorage be cointegrated the condition is in fact stronger requiring that the deficit inclusive of interest be stationary stationarity of the net of interest deficit is neither necessary nor sufficient for intertemporal budget balance however it does have implications for barro s tax smoothing hypothesis data for the period 1890 1986 are consistent with intertemporal budget balance but not with tax smoothing

government debt government spending and private sector behavior revisited comment perhaps no issue has generated as much controversy among economists in the past decade as the proposition that an increase in the government deficit induces an equal offsetting increase in private saving the truth of this so called ricardian equivalence proposition is central to whether budget deficits reduce capital accumulation to the feasibility of expansionary tax reductions and to the effects of social security on private saving and aggregate capital accumulation although the basic idea that the future tax liabilities associated with government deficits and debt induce individuals to increase their saving has been around since the time of david ricardo and was treated explicitly by don patinkin 1965 martin bailey 1971 and levis kochin 1974 the current debate was launched by robert barro 1974 the voluminous theoretical literature of recent years has shown that complete ricardian equivalence would be expected to prevail only under very special conditions see douglas bernheim 1987 for an especially useful survey and analysis but the theoretical restrictiveness of the assumptions required for complete ricardian equivalence does not constitute a practical refutation defenders of ricardian equivalence can argue that the theory is only an approximation and can claim that although the stringent conditions required for complete ricardian equivalence do not hold the economy s behavior in practice is close to the predictions of ricardian equivalence there are two key empirical questions the first is whether a higher level of taxes with government spending constant induces individuals to reduce their spending on consumption as traditional theory holds or has no effect on consumer spending as the ricardian equivalence proposition predicts the second deals with the effect of government outlays on goods and services although the absence of a negative effect on consumer spending of such government outlays is clearly contrary to the ricardian equivalence proposition the existence of a moderate negative effect of government outlays on consumer spending is not in itself evidence in favor of the ricardian equivalence proposition that individuals increase their saving to finance anticipated debt service as feldstein 1982 explained consumers may correctly believe that a rise in current government spending is a good indicator of a higher level of future government spending once a program is launched or budgets increased the process is unlikely to be reversed an increase in current government spending is therefore a good indication that future taxes will have to be higher to finance a higher level of future government spending individuals may rationally reduce their own spending when government outlays increase without a concurrent increase in taxes because they anticipate higher future taxes to finance higher future government spending even if they give little or no weight to the debt service implications of the current deficit the strongest direct evidence in favor of ricardian equivalence is roger kormendi s 1983 article in the american economic review he presents consumption regression equations that relate an estimate of consumption to net national product wealth martin feldstein is professor of economics at harvard university and president of the national bureau of economic research douglas elmendorf is assistant professor of economics at harvard university we are grateful to greg mankiw and lawrence summers for comments on an earlier draft the research reported here is part of the nber study of the government budget and the private economy ikormendi defines consumption as the sum of current expenditures on services and nondurables plus 10

new tests of the life cycle and tax discounting hypotheses abstract we first test a version of the permanent income consumption function recently suggested by barro the results support the theory except that consumption expenditures show sensitivity to transitory income next we use the consumption model to test the tax discounting hypothesis which is strongly supported this support for tax discounting disagrees with results from some earlier studies using more traditional specifications of the consumption function however we show that when certain obviously inadequate estimation procedures are corrected the traditional models also support tax discounting this uniform support for tax discounting suggests that the sensitivity of consumption to transitory income is not due to liquidity constraints

investment decisions in finite lived monopolies abstract this paper studies the value and optimal timing for investment in finite lived monopolies extending the literature on real option games by considering the cases of random and certain lived monopolies under these settings firms face the risk of demonopolization that can occur as a random or a certain event we show that these new settings produce significantly different results when compared to the canonical monopolistic and duopolistic models in a certain lived monopoly the leader invests sooner than in a duopoly if there is a risk of being preempted and later than in a monopoly if the leader role is pre assigned in a random lived monopoly entry occurs somewhere between the duopoly and monopoly cases higher uncertainty delays investment in all cases

replicating ricardian equivalence tests with simulated series this paper replicates standard consumption function tests of ricardian equivalence using series generated from a model which nests ricardian equivalence within a non ricardian alternative due to finite horizons and or distortionary taxation the author shows that the estimates of the effects of taxation on consumption are not robust and that standard tests may have weaknesses which can lead to conflicting results whether ricardian equivalence holds or not the simulations also show that no clear conclusions about ricardian equivalence can be drawn from observing a low correlation between the current account and government budget deficits copyright 1997 by american economic association

evaluating natural resource investments notwithstanding impressive advances in the theory of finance over the past 2 decades practical procedures for capital budgeting have evolved only slowly the standard technique which has remained unchanged in essentials since it was originally proposed see dean 1951 bierman and smidt 1960 derives from a simple adaptation of the fisher 1907 model of valuation under certainty under this technique expected cash flows from an investment project are discounted at a rate deemed appropriate to their risk and the resulting present value is compared with the cost of the project this standard textbook technique reflects modern theoretical developments only insofar as estimates of the discount rate may be obtained from crude application of single period asset pricing theory but see brennan 1973 bogue and roll 1974 turnbull 1977 constantinides 1978 the inadequacy of this approach to capital budgeting is widely acknowledged although not widely discussed its obvious deficiency is its the evaluation of mining and other natural resource projects is made particularly difficult by the high degree of uncertainty attaching to output prices it is shown that the techniques of continuous time arbitrage and stochastic control theory may be used not only to value such projects but also to determine the optimal policies for developing managing and abandoning them the approach may be adapted to a wide variety of contexts outside the natural resource sector where uncertainty about future project revenues is a paramount concern

finite lifetimes and the effects of budget deficits on national saving abstract even though realistic deficit policies shift sizable tax burdens to future generations the assumption of an infinite horizon is a good approximation for analyzing a deficit s short run saving effect on individuals who are neither liquidity constrained nor myopic recent u s experience casts significant doubt on these assumptions however and appears difficult to reconcile with the ricardian equivalence proposition that the timing of taxes does not affect national saving recent deficits have coincided with reduced national saving and a substantial increase in the share of gnp devoted to consumption

bond pricing and the term structure of interest rates a new methodology for contingent claims valuation this paper presents a unifying theory for valuing contingent claims under a stochastic term structure of interest rates the methodology based on the equivalent martingale measure technique takes as given an initial forward rate curve and a family of potential stochastic processee for its subsequent movements a no arbitrage condition restricts this family of processes yielding valuation formulae for interest rate sensitive contingent claims which do not explicitly depend on the market prices of risk examples are provided to illustrate the key results in relation to the term structure of interest rates arbitrage pricing theory has two purposes the first is to price all zero coupon default free bonds of varying maturities from a finite number of economic fundamentals called state variables the second is to price all interest rate sensitive contingent claims taking as given the prices of the zero coupon bonds this paper presents a general theory and a unifying framework for understanding arbitrage pricing theory in this context of which all existing arbitrage pricing models are special cases in particular vasicek 1977 brennan and schwartz 1979 langetieg 1980 ball and torous 1983 ho and lee 1986 schaefer and schwartz 1987 and artzner and delbaen 1988 the primary contribution of this paper however is a new methodology for solving the second problem i e the pricing of interest rate sensitive contingent claims given the prices of all zero coupon bonds the methodology is new because i it imposes its stochastic structure directly on the evolution of the forward rate curve ii it does not require an inversion of the term structure to eliminate the market prices of risk from contingent claim values and iii it has a stochastic spot rate process with multiple stochastic factors influencing the term structure the model can be used to consistently price and hedge all contingent claims american or european on the term structure and it is derived from necessary and more importantly sufficient conditions for the absence of arbitrage the arbitrage pricing models of vasicek 1977 brennan and schwartz 1979 langetieg 1980 and artzner and delbaen 1988 all require an iformerly titled bond pricing and the term structure of interest rates a new methodology

is ricardian equivalence a good approximation ricardian equivalence may be a good approximation even if all households have finite horizons many households have short horizons and an appreciable fraction of wage income is received by liquidity constrained households the approximation is likely to be better the more imperfect annuity markets are

real investment options with multiple sources of rare events abstract we value real investment options when the underlying asset follows a mixed jump diffusion process involving various types sources of rare events jumps these jumps are assumed independent of each other with each type having a log normally distributed jump size and a random poisson distributed arrival time they may represent uncertainties about the arrival and impact on the underlying investment of new information concerning technological innovation competition political risk regulatory effects and other sources an analytic solution is presented for european claims call or put options with multiple sources of jumps a discrete time markov chain methodology implemented within a finite difference scheme is proposed for the valuation of american as well as european options the approach is also applicable to financial options with multiple types of rare events the approach is illustrated through valuing complex real options with compound features involving interactions between optimal investment and subsequent operating decisions specifically we value a growth option and an extension option

assessing ricardian equivalence this paper reviews the literature on ricardian equivalence this hypothesis may be interpreted as a generalisation to the short and the long run of the theories which put no weight on the real effects of public policies on aggregate demand we argue that ricardian equivalence relies on both permanent income hypothesis and the fulfilment of the intertemporal government budget constraint the theoretical literature emphasises several reasons for departures from this hypothesis however the empirical literature is inconclusive when ricardian equivalence is tested in a life cycle framework the hypothesis is usually rejected while when the empirical analysis is based on optimising models it is usually accepted

options on the minimum or the maximum of two risky assets analysis and applications this paper provides analytical formulas for european put and call options on the minimum or the maximum of two risky assets the properties of these formulas are discussed in detail options on the minimum or the maximum of two risky assets are useful to price a wide variety of contingent claims of interest to financial economists applications discussed in this paper include the valuation of foreign currency debt option bonds compensation plans risk sharing contracts secured debt and growth opportunities involving mutually exclusive investments

optimal pension insurance design abstract in this paper we analyze how the traditional life and pension contracts with a guaranteed rate of return can be optimized to increase customers welfare given that the contracts have to be priced correctly we use individuals preferences to find the preferred design assuming crra utility we cannot explain the existence of any form of guarantees through numerical solutions we quantify the difference measured in certainty equivalents to the preferred merton solution of direct investments in a fixed proportion of risky and risk free assets the largest welfare loss seems to come from the fact that guarantees are effective by the end of each year not only by the expiry of the contract however the demand for products with guarantees may be explained through behavioral models we use cumulative prospect theory as an example showing that the optimal design is a simple contract with a life time guarantee and no default option

capital investment strategies under uncertain regulation this article presents a positive model of investment choices by regulated firms that offers rational explanations for electric utilities recent behavior of delaying investment and choosing smaller shorter lead time technologies the model assumes thatfirms capital investments require long lead times during which the value of the completed project is uncertain firms anticipate regulatory profit and loss restrictions but expectations about the value of a completed project change over time firms decisions are modelled using an option pricing approach that incorporates the value of flexibility to delay or abandon projects the article shows why rational firms invest in smaller shorter lead time plants or delay investment when faced with uncertain and asymmetric profit and loss restrictions it also looks at decisions to abandon partially completed plants and shows that the static result that a higher cost allowance on abandoned projects increases the incentive for investment is not generally true in a dynamic model

the sustainability of current account deficits abstract this paper proposes a new method of determining whether a country is likely to be able to sustain its current account deficits without defaulting on its debt it is based on the notion of the national intertemporal budget constraint ibc which is derived from a forward solution of the balance payments identity although the problem is formally similar to that considered in the literature on the government ibc a more general solution is obtained by allowing the primary deficit to be endogenous instead of exogenous it is shown that the existence of negative feedback from net indebtedness to the primary deficit a wealth effect is sufficient this method supplants the ad hoc approach previously adopted in the current account literature whilst many of the same variables appear a formal structure for analysing them is provided

the hidden costs of renewables promotion the case of crop based biogas abstract this paper finds that specific characteristics of bioenergy investments namely long times to build relatively high variable costs and the managerial ability of corrective actions during the project help bioenergy producers to respond to market uncertainties this effect is shown to compromise the economic effectiveness of bioenergy policies the paper compares the effectiveness of financial and regulatory incentive programs aiming to stimulate production of crop based biogas a stylized stochastic real options based investment model is developed to analyze the investment behavior of biogas producers under alternative policies the model is solved by a numerical approach combining stochastic simulations and the genetic algorithm technique unless bioenergy schemes account for structural characteristics of the bioenergy industry they will tend to encourage investments in unused production capacities this would cause additional welfare costs and benefit mainly crop producers

income uncertainty and ricardian equivalence this note characterizes the nature of ricardian equivalence failure when either the old generation s or the young generation s income is uncertain and the nonnegativity constraint on bequests is binding in some states of nature assuming a positive third derivative of the utility function the same condition needed for precautionary savings it is shown that the degree of failure of ricardian equivalence is greater when the corner has to do with parental poverty than when the corner has to do with children s wealth the reason is that in corners associated with parental poverty and therefore lower parental consumption marginal utility is more sensitive to extra consumption leading to a higher marginal propensity to consume in the first period consequently government transfers cause a substantial reduction of precautionary savings in poor corners in contrast to rich corners where precautionary savings are only slightly affected

an option valuation analysis of investment choices by a regulated firm this paper analyzes a utility power plant construction project using an option pricing model of the value of the capital investment it includes descriptive factors frequently ignored in the valuation of capital investments by regulated firms including lead time lumpy and sequential cost outlays irreversibility of expenditures and uncertainty about regulatory outcomes for completed projects the analysis shows the value of shorter lead time technologies the value of flexibility to delay or abandon construction the incentive to delay construction under uncertain regulation and how cost recovery policies such as possible disallowance of allow for funds used during construction afudc create incentives to invest less but to complete construction quickly the analysis may also apply in unregulated contexts where the value of a completed project is affected by taxation the possibility of nationalization or possible competitors actions that create uncertain restrictions on potential profits

consumers are not ricardian evidence from nineteen countries i introduction in conventional macroeconomic analysis government debt affects the economy because households view it as net wealth the larger the government debt is the wealthier households feel and the more they consume in principle however households need not view government debt as net wealth david ricardo pointed out that they might conceivably treat the future taxes servicing the government debt as exactly offsetting it 1 robert barro 1974 has shown that maximizing households will actually do so if they accurately anticipate future taxes if they face perfect capital markets and if they have effectively infinite horizons ricardian equivalence is said to hold if households do treat future servicing taxes as an exact offset to the government debt many empirical papers on consumption have investigated whether ricardian equivalence is consistent with observation kochin 1974 barro 1978 tanner 1979 seater 1982 kormendi 1983 aschauer 1985 seater and mariano 1985 kormendi and meguire 1986 1990 leiderman and razin 1988 evans 1988 and evans and hasan 1993 have reported evidence consistent with ricardian equivalence by contrast blinder and deaton 1985 feldstein 1978 1982 boskin and kotlikoff 1985 modigliani and sterling 1986 1990 and feldstein and elmendorf 1990 have reported evidence inconsistent with ricardian equivalence unfortunately most of these studies do not estimate regression equations that derive from well specified theoretical models nesting both ricardian equivalence and an alternative theory in which budget deficits and current taxes are not equivalent consequently their results are often hard to interpret moreover these studies consider the data for only one country typically the united states as a result the tests that are performed may not have much power to distinguish an economy for which ricardian equivalence would be a good approximation from one for which it would be a bad approximation olivier blanchard 1985 has provided one of the few models in the literature that tractably nests ricardian equivalence and an alternative in which households view government debt as net wealth depending upon whether a crucial parameter is zero or positive households have infinite horizons internalize all future generations and exhibit ricardian behavior or have finite horizons are at least somewhat disconnected from future generations and exhibit non ricardian behavior that strengthens as the parameter becomes larger the model has testable implications that this paper examines using annual data for nineteen countries when the data for the countries are pooled the tests have sufficient power not only to reject ricardian equivalence in favor of blanchard s alternative but also to yield a precise estimate of the deviation from ricardian equivalence this estimated deviation is approximately what one would expect if capital and insurance markets were perfect and households did not have altruistic bequest motives the deviation is however also economically unimportant for many purposes the rest of the paper is organized as follows section ii lays out blanchard s model and derives the testable implications of ricardian equivalence section iii tests these implications section iv summarizes the findings of the paper and interprets them ii empirical implications of ricardian equivalence in the stochastic variant of blanchard s model formulated in this section the economy is inhabited by a constant population of households that have finite horizons and face perfect capital and insurance markets 2 each household has a finite horizon because it has a probability p of dying each period and being replaced by another household from which it is entirely disconnected with the population normalized to unity the number of households born 0 1 2 periods earlier is always p p 1 p p 1 p sup

regulation and corporate investment policy in a previous paper it was shown that the traditional rule that the allowed return on the equity of a regulated firm should be set equal to its cost of equity capital was conceptually deficient 2 this deficiency arises because the cost of equity capital of a regulated firm depends upon its risk which depends in turn upon the regulatory policy that will be followed in the future including the allowed rate of return it was argued therefore that this traditional rule should be replaced by the requirement that the regulatory policy be consistent a consistent regulatory policy achieves what the traditional rule only attempts it ensures that at the time of a regulatory hearing the market value of the firm equity is equal to the equity financed portion of the rate base to devise a consistent regulatory policy it is necessary to have a valuation model which takes explicit account of regulatory policy such a model was developed in the above mentioned paper in this paper we generalize the earlier valuation model so that the investment policy of the regulated firm is determined by the value maximizing decisions of the management instead of being taken as exogenous to the extent that investment policy is discretionary its endogeneity must be taken into account in devising a consistent regulatory policy and this is made possible by the generalized model in reality it seems unclear to what extent the investment policies of regulated firms are predetermined by the requirement that they meet demand and to what extent they are discretionary since the model presented here easily accommodates constraints on the investment policy it is the more appropriate model so long as there exists any element of discretionary investment behaviour and permits a more adequate approach to the determination of consistent regulatory policies with discretionary investment policy an important consequence of any particular consistent regulatory policy is the investment policy it induces in section 4 we show how the value maximizing investment policy is affected by the choice of regulatory policy on the other hand regulated firms are wont to argue that their investments are in the main predetermined by demand and must be undertaken regardless of their profitability this putative lack of discretion it is maintained means that the appropriate allowed rate of return is higher than would otherwise be the case in section 4 also we evaluate the strength of this consideration by comparing the allowed rate of return under consistent regulatory policies when investment policy is and is not discretionary section 5 shows briefly how the analysis can be extended to account for the effect of debt in the capital structure

government debt government spending and private sector behavior a current period tax reduction financed by issuing government debt shifts the timing of tax collection from the current period to the future if the future taxes implied by government debt are not fully perceived and discounted by the private sector there will be a net wealth effect that increases private sector consumption thus reducing capital accumulation and growth if on the other hand the implied future taxes are perceived and discounted by the private sector the current period tax reduction will be used to increase private saving to pay for the future taxes and government debt will be absorbed without any real effects on the economy the effects of government spending financed by current period taxation also depend upon private sector perceptions 2 if the benefits of government spending are ignored private sector consumption will decrease in accordance with the reduction in permanent disposable income to the extent that government spending is on consumption type goods that are perceived as substitutes for privately provided consumption goods there will be a relatively greater reduction in private sector consumption to the extent that government spending is on investment type goods yielding future goods and services that are perceived as substitutes for future privately provided consumption goods there will be a relatively smaller reduction in private sector consumption the standard approach to modeling private sector consumption saving behavior involves a rather asymmetric set of assumptions as to how the private sector perceives the various elements of government fiscal policy 3 current period taxes are assumed to be fully perceived but current period government spending is implicitly assumed to be completely ignored by the private sector in considering permanent personal disposable income the private sector is assumed to be forward looking in its assessment of income and taxation the stock of government debt is nevertheless included as part of the stock of private wealth the implicit assumption associate professor of economics graduate school of business university of chicago 1101 east 58th street chicago il 60637 i thank eugene fama levis kochin michael mussa paul evans and an anonymous referee for helpful comments i am particularly grateful to daniel benjamin for contributing many hours of discussion and laura lahaye who was a research assistant and valuable adviser on earlier drafts the theoretical debate on the burden of the debt has been long standing gerald o driscoll 1977 documents ricardo s nineteenth century position robert barro 1974 reopened the debate by introducing the fundamental issue of intergenerational transfers also discussed in merton miller and charles upton 1974 the empirical side of the debate was initiated by levis kochin s 1974 attempt to test for the effects of deficits on consumption and by martin feldstein s 1974 attempt to test for the effects of social security wealth on consumption other empirical contributions include jess yawitz and laurence meyer 1976 myself 1978 and j earnest tanner 1978 1979 with respect to the effects of government deficits and debt and barro 1978 michael darby 1979 and dean leimer and selig lesnoy 1982 with respect to social security wealth see also interesting recent papers by john seater 1982 who generates detailed tests of the effects of deficits and debt on consumption charles plosser 1982 who explores the effects of government spending and debt shocks on interest rates and feldstein 1982 who attempts tests similar to some in this paper see fn 29 2martin bailey s 1962 1971 development of the effects of government spending on private consumption and aggregate economic activity is the seminal contribution paul david and john scadding 1974 extend bailey s ideas and provide some supporting empirical evidence more recently willem buiter 1977 and myself 1978 developed models based on bailey s earlier work barro 1981 has an interesting paper on related issues see also david aschauer 1982 3the standard approach incorporates fiscal policy through the concept of personal disposable income and by including the stock of government debt as part of personal wealth see for example the empirical specification of albert ando and franco modigliani 1963 which has been the basis of most empirical consumption studies since and feldstein 1974 for one of the more influential papers based on the ando modigliani specification

dynamic r d investment policies this paper examines dynamic r d investment policies and the valuation of r d programs in a contingent claims framework we incorporate the following characteristics of r d programs into our model learning by doing collateral learning between different projects in the program interaction between project cash flows periodic reevaluations of the program different intensities of investment capital rationing constraints and competition we show that a firm may invest in multiple projects even if only one can be implemented after development is complete furthermore the firm may significantly alter its funding policy over time for example it may simultaneously develop multiple projects for a period of time then focus on a lead project and potentially resume funding of a backup project if the lead project fails to deliver on its early promise we show how a firm can forecast expected r d spending through time for an optimally executed r d program while project volatility plays an important role in determining r d program value we find that for high volatility projects the optimal investment policy is not very sensitive to changes in or misestimation of volatility in considering whether to accelerate development of a project a firm should balance the adverse effects of increased costs and the loss of investment flexibility against the positive effects of rapid uncertainty resolution and accelerated cash flows in the presence of a budget constraint that prevents the firm from simultaneously accelerating projects and developing projects in parallel we find that if one project significantly dominates another early in the development stage the option to accelerate the lead project is likely to be more valuable than the option to exchange projects thus the backup project would be shelved in order to commit extra resources to development of the lead project finally competition from other firms leads to more parallel investment in the early development stages of projects less parallel investment in the latter stages of development and lower overall investment

asset and liability management for insurance products with minimum guarantees the uk case abstract modern insurance products are becoming increasingly complex offering various guarantees surrender options and bonus provisions a case in point are the with profits insurance policies offered by uk insurers while these policies have been offered in some form for centuries in recent years their structure and management have become substantially more involved the products are particularly complicated due to the wide discretion they afford insurers in determining the bonuses policyholders receive in this paper we study the problem of an insurance firm attempting to structure the portfolio underlying its with profits fund the resulting optimization problem a non linear program with stochastic variables is presented in detail numerical results show how the model can be used to analyze the alternatives available to the insurer such as different bonus policies and reserving methods

an investigation of ricardian equivalence in a common trends model abstract to empirically discriminate between ricardian and non ricardian behaviour we have to use a method that distinguishes between expected and unexpected as well as permanent and transitory changes in taxes and government consumption one method that provides these distinctions between different types of changes is the common trends framework used in this paper which is a var model with cointegrating constraints in the empirical study of us data there is some support for the ricardian hypothesis but there are also some deviations from its predictions however the differences do not lend support to a keynesian view of budget deficits but rather to the view of expansionary fiscal contractions this can be motivated theoretically by uncertainty about future taxes in combination with prudent households

project management under risk using the real options approach to evaluate flexibility in r d managerial flexibility has value in the context of uncertain r d projects as management can repeatedly gather information about uncertain project and market characteristics and based on this information change its course of action this value is now well accepted and referred to as real option value we introduce in addition to the familiar real option of abandonment the option of corrective action that management can take during the project the intuition from options pricing theory is that higher uncertainty in project payoffs increases the real option value of managerial decision flexibility however r d managers face uncertainty not only in payoffs but also from many other sources we identify five example types of r d uncertainty in market payoffs project budgets product performance market requirements and project schedules how do they influence the value from managerial flexibility we find that if uncertainty is resolved or costs revenues occurafter all decisions have been made more variability may smear out contingencies and thus reduce the value of flexibility in addition variability may reduce the probability of flexibility ever being exercised which also reduces its value this result runs counter to established option pricing theory intuition and contributes to a better risk management in r d projects our model builds intuition for r d managers as to when it is and when it is not worthwhile to delay commitments for example by postponing a design freeze thus maintaining flexibility in r d projects

time to build option value and investment decisions abstract investment decisions and outlays are often made sequentially for example the rate at which construction proceeds is usually flexible and can be adjusted with the arrival of new information traditional discounted cash flow methods which treat the pattern of investment as fixed ignore this flexibility and understate the value of the project this paper uses contingent claims analysis to derive optimal decision rules and to value such investments we determine the effects of time to build opportunity cost and uncertainty on the investment decision for reasonable parameter values we show how a simple npv rule can lead to gross errors