residential construction using the urban growth model to estimate housing supply abstract this article presents an empirical model of housing supply derived from urban growth theory this approach describes new housing construction as a function of changes in house prices and costs rather than as a function of the levels of those variables which previous studies have used empirical tests support this specification over the leading alternative models our estimates show that a 10 rise in real prices leads to an 0 8 increase in the housing stock which is accomplished by a temporary 60 increase in the annual number of starts spread over four quarters

valuing water supply reliability instead of creating water supply systems that fully insulate mankind from climate imposed water deficiencies it is possible that for municipal water systems a nonzero probability of water supply shortfall is efficient perfect water supply reliability meaning no chance of future shortfall is not optimal when water development costs are high designing an efficient strategy requires an assessment of consumer preferences pertaining to the reliability of water supply contingent valuations of both current and future shortfalls are reported the consistency of these measures is gauged using an expected utility model copyright 2000 oxford university press

bounded growth of the bullwhip effect under a class of nonlinear ordering policies abstract this paper analyzes the bullwhip effect in multi echelon supply chains under a general class of nonlinear ordering policies a describing function approach from control theory is used to derive closed form formulas to predict amplification of order fluctuations along the supply chain it is proven that with consideration of nonlinearity in the ordering policy the magnitude of the bullwhip effect will eventually become bounded after growing through the first few stages of the supply chain it is also proven that the average customer demand as well as the demand fluctuation frequency would directly affect the bounded magnitude while the suppliers demand forecasting method has no effect at all for illustration analytical results for a class of order up to policies are derived and verified by numerical simulations the proposed modeling framework holds the promise to not only explain empirical observations but also serve as the basis for developing counteracting strategies against the bullwhip effect

the informal sector and the macroeconomy a computable general equilibrium approach for peru abstract this paper examines the macroeconomic implications of the informal sector in peru through the use of a structuralist computable general equilibrium model the lack of formal sector employment drives informal activity while formal and informal output are treated as imperfect substitutes simulations show that informal activity reduces the keynesian multiplier and complicates distributional issues as the income of formal workers and informal producers can move in opposite directions a final simulation highlights the limitations of strategies designed to promote the informal sector total output and income of informal producers decline following an increase in productivity in these processes

the conditional effect of specialized governance on public policy what are the policy consequences of creating functionally specialized venues for decision making this study directly compares special districts with general purpose local governments to evaluate how specialization influences responsiveness and policy choice previous theorizing has assumed that specialization should have the same effect across all policy contexts the findings presented here show instead that its effect is conditional on the status of public problems objective conditions related to a policy issue more strongly influence the responsiveness of multipurpose legislatures than that of special districts thus the institutional effect of functional specialization varies with the severity of the public problem the result is that governing structure matters most where problems are least severe the findings demonstrate the importance of considering policy context when analyzing the effects of political institutions

avoiding the bullwhip effect using damped trend forecasting and the order up to replenishment policy we study the damped trend forecasting method and its bullwhip generating behaviour when used within the order up to out replenishment policy using z transform transfer functions we determine complete stability criteria for the damped trend forecasting method we show that this forecasting mechanism is stable for a much larger proportion of the parametrical space than is generally acknowledged in the literature we provide a new proof to the known fact that the naive exponential smoothing and holts method forecasting when used inside the out policy will always generate bullwhip for every possible demand process for any lead time further we demonstrate the damped trend out system behaves differently sometimes it will generate bullwhip and sometimes it will not bullwhip avoidance occurs when demand is dominated by low frequency harmonics in some instances in other instances bullwhip avoidance happens when demand is dominated by high frequency harmonics we derive sufficient conditions for when bullwhip will definitely be generated and necessary conditions for when bullwhip may be avoided we verify our analytical findings with a numerical investigation

is water policy limiting residential growth evidence from california rapid population growth and increasing water costs have led western states to condition development on long term water availability using original survey data this paper examines the effects of water screening policies on california s housing supply from 1994 to 2003 panel regressions indicate that these policies significantly slowed housing growth however impact fees based on the costs of residential water connections do not have this effect and may constitute a preferred policy to enhance the social efficiency of screening policies regulators should encourage the adoption of conservation oriented water rates which are associated with significant savings in residential water use

on the theory of growth controls numerous empirical studies have examined the effect of growth controls on housing prices these studies have used many different techniques ranging from hedonic price model estimation to paired comparisons but have all come to the same conclusion growth controls raise the price of housing in theory there are both demand and supply side explanations which need not be mutually exclusive for these observed price differences on the supply side housing caps zoning restrictions limitations on the amount of developable land and other forms of growth control may reduce the supply of housing over time this in turn may produce scarcity effects which manifest as shifts or other changes in the housing supply curve and attendant price increases on the demand side to the extent that growth controls may reduce or internalize expected negative externalities and or congestion costs associated with growth controls may also produce amenity effects such amenity effects manifest as changes in the demand curve and likewise may be capitalized in land values and wages e g the price of a house rises as commute time falls

alternatives to coca production in bolivia a computable general equilibrium approach pressured and aided by the united states bolivia has reembarked on a program to eradicate the cultivation of coca used for cocaine production over the next three years the united states plans to inject us soo million into bolivia to wean the country from producing drugs and replace the cultivation of coca with other crops and agricultural activities previous research has shown that coca cultivation and cocaine production benefits the bolivian economy de franc0 and godoy 1992 by raising income creating employment and increasing the availability of credit particularly for smallholders and the informal sector melvin and ladman 1991 given that the macroeconomic impact of a reduction in coca leaf production could devastate the economy the bolivian government has little economic or political incentive to eradicate coca a solution could be to find substitute crops and agricultural activities which would provide comparable levels and distribution of income we use a computable general equilibrium cge model to study the effects of alternatives to coca production the model contains 38 sectors and four social classes the model allows for a detailed assessment of the economic feasibility of switching from coca to other crops in the simulations we reduce coca production and allow each substitute to adjust to restore the real income of smallholders which existed before eradication twenty one crops are then ranked by the feasibility of the needed price and output change the effect on gross domestic product gdp inflation and workers real incomes the results of the simulations suggest that sugar cattle forestry and maize are the strongest candidates for a coca substitution program but there are practical complications in implementing each of the substitutes as will be discussed below indeed the results of this study justify the reluctance on the part of the bolivian authorities to fully cooperate with us efforts to eradicate coca section 2 provides the background to bolivia s coca dependence in section 3 we develop the model and in section 4 we present the equations and an explicit closure statement for the model the results of the simulations are discussed in section 5 the conclusion section 6 contains a discussion of the problems likely to surface in implementing alternatives to coca cultivation

an empirical estimation of the price effects of development impact fees empirical analysis of the price of vacant lots sold in three toronto suburban municipalities during the 1977 86 period shows that development impact fees directly increased lot prices by approximately 1 2 times the size of the fee the extent of the increase was related to city growth rates in general the faster the rate of growth the lower was the price effect of development impact fees the effects of growth however were not consistent across the three municipalities as one municipality appeared to be lowering its fees in response to reductions in growth rates the policy environment within which fees are implemented and the way fees are adjusted appear to influence their effect on lot prices the estimated model also suggests that increases in expected future construction costs reduce current lot prices general increases in the consumers shelter costs tend to inflate the price of vacant lots the expectation of future increases in the cost of land development whether it is due to increases in ma

potato led growth the macroeconomic effects of technological innovations in bolivian agriculture through the use of a computable general equilibrium model we measure the economy wide effects of improving the production technology of relatively non traded staples potatoes maize import crops wheat and export crops soybeans in bolivia the results of the analysis suggest that technological innovations in the production technology of potatoes would benefit the bolivian economy most we discuss the reasons for the limited effects of technological innovations in tradeable crops

coca dollars and the dollarization of south america a unique data set on the informal loan market in a coca growing region of bolivia is used to explore the hypothesis that the dollarization of this market is related to the coca industry implications are then drawn for other nations where coca or cocaine is an important industry the authors find that loans are significantly more likely to be denominated in dollars in the season of the major coca harvest than at any other time of the year the effects of the term and size of loans is consistent with the financial needs of the drug industry which is highly dollarized copyright 1991 by ohio state university press

analyzing the effect of the inventory policy on order and inventory variability with linear control theory in this paper we apply linear control theory to study the effect of various inventory policies on order and inventory variability which are key drivers of supply chain performance in particular we study a two echelon supply chain with a stationary demand pattern under the influence of three inventory policies an inventory on hand policy that bases orders on the visible inventory at an installation an installation stock policy that bases orders on the inventory position on hand plus on order inventory at an installation and an echelon stock policy that bases orders on the inventory position at that installation and all downstream installations we prove analytically that the inventory on hand policy is unstable in practical settings confirming analytically what has been observed in experimental settings and in practice we also prove that the installation stock and echelon stock policies are stable and analyze their effect on order and inventory fluctuation specifically we show the general superiority of the echelon stock in our setting and demonstrate analytically the effect of forecasting parameters on order and inventory fluctuations confirming the results in other research

colombia s income from the drug trade abstract we estimate the net dollar proceeds that colombia receives from the drug trade making use of production data recently compiled by us authorities care is taken in assuring that our estimations are consistent with previous research on cocaine consumption in the united states and production in bolivia and peru we show that net dollar proceeds which used to represent around 7 of gdp and 70 of exports in the early 1980s now represent around 3 of gdp and 25 of exports these numbers though significant pale in comparison with those suggested in the popular press according to which colombia s economy has been all but overtaken by the drug trade

information distortion in a supply chain the bullwhip effect this article originally appeared in management science april 1997 volume 43 number 4 pp 546 558 published by the institute of management sciences consider a series of companies in a supply chain each of whom orders from its immediate upstream member in this setting inbound orders from a downstream member serve as a valuable informational input to upstream production and inventory decisions this paper claims that the information transferred in the form of orders tends to be distorted and can misguide upstream members in their inventory and production decisions in particular the variance of orders may be larger than that of sales and distortion tends to increase as one moves upstream a phenomenon termed bullwhip effect this paper analyzes four sources of the bullwhip effect demand signal processing rationing game order batching and price variations actions that can be taken to mitigate the detrimental impact of this distortion are also discussed

the bullwhip effect progress trends and directions the bullwhip effect refers to the phenomenon where order variability increases as the orders move upstream in the supply chain this paper provides a review of the bullwhip literature which adopts empirical experimental and analytical methodologies early econometric evidence of bullwhip is highlighted findings from empirical and experimental research are compared with analytical and simulation results assumptions and approximations for modelling the bullwhip effect in terms of demand forecast delay replenishment policy and coordination strategy are considered we identify recent research trends and future research directions concerned with supply chain structure product type price competition and sustainability

inventories and the volatility of production a stylized fact associated with inventory behavior is that the variance of production exceeds the variance of sales this paper presents a model of production decisions with demand uncertainty that incorporates no nnegativity constraints on inventories even with no productivity shocks optimal behavior by the firm is consistent with this stylized fact either if demand exhibits positive serial correlation or if the firm can backlog excess demand the reason is that a demand shock affects both the actual inventory level given unchanged production and the desired level production must replenish the stock and adjust to the new desired level copyright 1987 by american economic association

an empirically simulated investigation of the impact of demand forecasting on the bullwhip effect evidence from u s auto industry this study empirically examines the impacts of three major aspects of demand forecasting on the magnitude of the bullwhip effect three research questions are addressed to investigate the association between 1 forecast accuracy 2 aggregate forecasting and 3 responsive forecasting and the bullwhip effect using forecasted demand generated from popular time series forecasting models and real life demand data the study investigates the relationship between the forecasted results and the consequential bullwhip effect the findings show that the forecasting methods used lead to the variation of the bullwhip effect moreover the lead time reduction and the stable demand forecast are beneficial to reduce the bullwhip effect however our empirical results differ from previous findings in two ways i improving forecast accuracy does not necessarily reduce the bullwhip effect and ii aggregate forecasting does not always reduce the bullwhip effect

the impact of information enrichment on the bullwhip effect in supply chains a control engineering perspective this paper examines the beneficial impact of information sharing in multi echelon supply chains we compare a traditional supply chain in which only the first stage in the chain observes end consumer demand and upstream stages have to base their forecasts on incoming orders with an information enriched supply chain where customer demand data e g epos data is shared throughout the chain two types of replenishment rules are analysed order up to out policies and smoothing policies policies used to reduce or dampen variability in the demand for the class of out policies we will show that information sharing helps to reduce the bullwhipeffect variance amplification of ordering quantities in supply chains significantly especially at higher levels in the chain however the bullwhip problem is not completely eliminated and it still increases as one moves up the chain for the smoothing policies we show that information sharing is necessary to reduce order variance at higher levels of the chain the methodology is based on control systems engineering and allows us to gain valuable insights into the dynamic behaviour of supply chain replenishment rules we also introduce acontrolengineering based measure to quantify the variance amplification bullwhip or variance reduction

demand side technology standards under inefficient pricing regimes when price setting regulators haveobjectives other than maximizing socialsurplus the conservation potential ofdemand side technology standards can besignificantly diminished this paperdemonstrates this by empirically recovering thesocially sub optimal preferences of a group ofwater managers in a groundwater dependentregion of california and simulating theirinefficient price response to the mandatedadoption of low flow appliances by homeowners the resulting reduction in the conservationpotential of these appliances is quantified and a modest tax is shown to be a relativelycost effective policy tool for conservation if non price conservation policies arepreferred according to equity criteria thepaper suggests that in order to preserve theirconservation potential policy makers should berequired to continue to set prices as if notechnology standards had been introduced

testing for strategic interaction among local governments the case of growth controls this paper helps to fill a gap in the public economics literature by providing empirical evidence on strategic interaction among local governments using the methodology of case et al journal of public economics 52 285 307 1993 the paper focuses on the adoption of growth control measures by cities in california and looks for evidence of policy interdependence in these choices the data are drawn from an elaborate survey of growth control practices in california cities conducted by glickfeld and levine regional growth local reaction lincoln institute of land policy cambridge ma 1992 the survey results are used to compute an index of the stringency of growth controls in each city which serves as the dependent variable for the study

demand evolution in stochastic inventory systems riskiness increase abstract this paper characterizes demand evolution in the steady state under common inventory policies in a single location stochastic inventory system our results show that downstream demand nonstrictly second degree stochastically dominates upstream orders and the bullwhip effect occurs we provide the link between demand evolution and utility theory for stochastic inventory systems our model is general in that ultimate customer demand follows an arbitrary stationary distribution and the facility may arbitrarily select policy parameters

fill rate in a periodic review order up to policy under auto correlated normally distributed possibly negative demand we investigate the inventory service metric known as the fill rate the proportion of demand that is immediately fulfilled from inventory the task of finding analytical solutions for general cases is complicated by a range of factors including correlation in demand double counting of backlogs and proper treatment of negative demand in the literature two approximate approaches are often proposed our contribution is to present a new fill rate measure for normally distributed auto correlated and possibly negative demand we treat negative demand as returns our approach also accounts for accumulated backlogs the problem reduces to identifying the minimum of correlated normally distributed bivariate random variables there exists an exact solution but it has no closed form however the solution is amenable to numerical techniques and we present a custom microsoft excel function for practical use numerical investigations reveal that the new fill rate is more robust than previous measures existing fill rate measures are likely to cause excessive inventory investment especially when fill rate targets are modest a strongly positive or negative autocorrelation in demand is present or negative demands exist our fill rate calculation ensures that the target fill rate is achieved without excessive inventory investments

the extension and exploitation of the inventory and order based production control system archetype from 1982 to 2015 in 1994 through classic control theory john naim and towill developed the automatic pipeline inventory and order based production control system apiobpcs which extended the original iobpcs archetype developed by towill in 1982 well recognised as a base framework for a production planning and control system due to the prevalence of the two original models in the last three decades in the academic and industrial communities this paper aims to systematically review how the iobpcs archetypes have been adopted exploited and adapted to study the dynamics of individual production planning and control systems and whole supply chains using various databases such as scopus web of science google scholar 111 papers we found that the iobpcs archetypes have been studied regarding the a modification of four inherent policies related to forecasting inventory lead time and pipeline to create a family of models b adoption of the iobpcs family to reduce supply chain dynamics and in particular bullwhip c extension of the iobpcs family to represent different supply chain scenarios such as order book based production control and closed loop processes simulation is the most popular method adopted by researchers and the number of works based on discrete time based methods is greater than those utilising continuous time approaches most studies are conceptual with limited practical applications described future research needs to focus on cost flexibility and sustainability in the context of supply chain dynamics and although there are a few existing studies more analytical approaches are required to gain robust insights into the influence of nonlinear elements on supply chain behaviour also empirical exploitation of the existing models is recommended

infrastructure financing and urban development abstract historically additions to public infrastructure necessitated by urban growth have been financed under a cost sharing approach in the last several decades however financing of growth has increasingly relied on land use exactions where new residents pay for the cost of incremental infrastructure despite the emergence of a formal growth control literature there has been virtually no formal analysis of the connection between infrastructure financing and urban development to provide such an analysis this paper investigates three different schemes for financing incremental infrastructure within an urban growth model the analysis compares an impact fee scheme to two types of cost sharing schemes deriving the effects on urban growth and land values of switching to the impact fee scheme the efficient financing scheme is also identified

the bullwhip effect on inventory a perspective on information quality abstractin recent years there has been a vast increase in the quantity of information shared across supply chain we investigate how the timeliness and accuracy of information quality affect the value of information sharing we use the inventory bullwhip effect bwe to measure the value of information sharing in a two level supply chain consisting of one retailer and one manufacturer the retailer faces a price sensitive demand and the price is an ar 1 process our study shows if customer demand and retailer s immediate order are delayed using retailer s historical order quantity to forecast can decrease manufacturer s bwe if information errors happen during delivery and utilization information sharing is not always valuable for the manufacturer sometimes no information sharing can decrease much more of bwe if information errors occur when the retailer collects demand information value of information sharing is more significant than when there are no information errors

price and income elasticities of residential water demand a meta analysis this article presents a meta analysis of variations in price and income elasticities of residential water demand meta analysis constitutes an adequate tool to synthesize research results by means of an analysis of the variation in empirical estimates reported in the literature we link the variation in estimated elasticities to differences in theoretical microeconomic choice approaches differences in spatial and temporal dynamics as well as differences in research design of the underlying studies the occurrence of increasing or decreasing block rate systems turns out to be important with respect to price elasticities the use of the discrete continuous choice approach is relevant in explaining observed differences

an econometric analysis of coca eradication policy in colombia abstract we estimate an econometric model of coca production in colombia our results indicate that coca eradication is an ineffective means of supply control as farmers compensate by cultivating the crop more extensively the evidence further suggests that incentives to produce legal substitute crops may have greater supply reducing potential than eradication

seasonal exponential smoothing with damped trends in this paper we apply the strategy of trend damping to the popular winters exponential smoothing systems for seasonal time series efficient model formulations are derived for both multiplicative and additive seasonal patterns an algorithm is given to test the stability of the models in cases where predetermined smoothing parameters are used empirical results are presented to show that trend damping improves ex ante forecast accuracy in seasonal data especially at long leadtimes

a pragmatic approach to the design of bullwhip controllers it is well known that forecasting mechanisms can greatly increase bullwhip demand variance amplification of orders as processed by both human and algorithmic decision makers this paper is concerned with the application of the well established apiobpcs decision support system a variant of the order up to rule in such circumstances it has two feedback controls based on the inventory and the orders in pipeline respectively with gains set equal according to the deziel eilon rule there is one feed forward control based on exponential forecasting although this is not a restriction on the application of this system we consider the pragmatic role of apiobpcs in the situation where the echelon decision maker may be handling a wide range of sku s in a non altruistic environment where upmarket information may either be withheld or simply unavailable under such circumstances it has been established via site based studies that the decision makers output the orders reflect a wide range of strategies or maybe ignorance three strategies may be regarded as appropriate i e pass orders along demand smoothing and level scheduling depending on context apiobpcs can be adapted to each of these modus operandi in the first case with the added capability of smoothing the sharp edges with a modicum of inventory variation and in the last case with the advantage of built in trend detection players in non altruistic supply chains must be able to cope with added uncertainties due to lead time variations we show that apiobpcs may be well matched to such situations and is hence copable as well as capable the paper includes recommended parameter settings according to desired decision making policies

characterization of the bullwhip effect in linear time invariant supply chains some formulae and tests the authors analyze the bullwhip effect in multistage decentralized supply chains operated with linear and time invariant inventory management policies the focus is on robustness the supply chain is modeled as a single input single output control system driven by arbitrary customer demands the authors derive robust analytical conditions to predict the presence of the bullwhip effect and bound its magnitude based only on the way inventories are managed these results hold independently of the customer demand the authors also characterize the stream of orders placed at any stage of the chain when the customer demand process is known and ergodic and give an exact formula for the variance of the orders placed this formula generalizes existing results by broadening the class of inventory replenishment policies and customer demand processes to which it applies the authors also show that the bullwhip effect can be mitigated by introducing commitments for future orders into the ordering policies

measuring and avoiding the bullwhip effect a control theoretic approach an important contributory factor to the bullwhip effect i e the variance amplification of order quantities observed in supply chains is the replenishment rule used by supply chain members first the bullwhip effect induced by the use of different forecasting methods in order up to replenishment policies is analysed variance amplification is quantified and we prove that the bullwhip effect is guaranteed in the order up to model irrespective of the forecasting method used thus when production is inflexible and significant costs are incurred by frequently switching production quantities up and down order up to policies may no longer be desirable or even achievable in the second part of the paper a general decision rule is introduced that avoids variance amplification and succeeds in generating smooth ordering patterns even when demand has to be forecasted the methodology is based on control systems engineering and allows important insights to be gained about the dynamic behaviour of replenishment rules