the resilience of employment in wales through recession and into recovery sensier m and artis m the resilience of employment in wales through recession and into recovery regional studies the dimensions of resilience of the welsh employment cycle are assessed the welsh economy has undergone reorientation and renewal since the deep crisis of the 1980s and it was more resistant than the uk for the 1990s crisis and has recovered its pre recession peak for the most recent crisis to visualize the regional spread of the most recent recession in wales turning points in unitary authority unemployment claims are dated and a series of maps show when welsh authorities entered recession it is found that the housing sector and manufacturing survey data are the best predictors of the welsh employment cycle

grim down south the determinants of unemployment increases in british cities in the 2008 2009 recession lee n grim down south the determinants of unemployment increases in british cities in the 2008 2009 recession regional studies this paper investigates the impact of the 2008 2009 recession on unemployment in the sixty largest cities in great britain the key determinant of changes in unemployment was the skills of the population with highly skilled cities experiencing smaller increases cities with employment in financial services or manufacturing sectors experienced larger increases in unemployment whether a city has a specialized or a diverse economy appears less important than the industries in which the city is specialized the results highlight a problem as the largest unemployment increases were in cities seen as having least potential for future growth

who works in a working region inclusive innovation in the new manufacturing economy abstractwho works in a working region inclusive innovation in the new manufacturing economy regional studies scholars have documented economic gains for regions that promote manufacturing through co location of innovation and production activities but it is unclear whether the production jobs created in this new context remain inclusive of workers with limited formal education this paper compares us states that specialize in biopharmaceuticals to understand who participates in a so called working region while some state policy makers have privileged scientific and design occupations at the expense of the production workforce regional actors in north carolina have increased employment in design and development while growing their biopharmaceutical production base aligning innovation and equity goals in the process

employment protection and product market competition a firm facing employment protection will defend its market position more fiercely than a rival firm operating without such restrictions however ex ante such firms may be more reluctant to expand for the benchmark case of contest competition the defensive effect dominates a firm facing employment protection has a stronger average market position

dynamic capacity management with substitution we examine a multiperiod capacity allocation model with upgrading there are multiple product types corresponding to multiple classes of demand and the firm purchases capacity of each product before the first period within each period after demand arrives products are allocated to customers customers who arrive to find that their product has been depleted can be upgraded by at most one level we show that the optimal allocation policy is a simple two step algorithm first use any available capacity to satisfy same class demand and then upgrade customers until capacity reaches a protection limit so that in the second step the higher level capacity is rationed we show that these results hold both when all capacity is salvaged at the end of the last demand period as well as when capacity can be replenished in the latter case an order up to policy is optimal for replenishment although finding the optimal protection limits is computationally intensive we describe bounds for the optimal protection limits that take little effort to compute and can be used to effectively solve large problems using these heuristics we examine numerically the relative value of strictly optimal capacity and dynamic rationing the value of perfect demand information and the impact of demand and economic parameters on the value of optimal substitution

commuting migration and local employment elasticities many changes in the economic environment are local including policy changes and infrastructure investments the effect of these changes depends crucially on the ability of factors to move in response therefore a key object of interest for policy evaluation and design is the elasticity of local employment to these changes in the economic environment we develop a quantitative general equilibrium model that incorporates spatial linkages between locations in goods markets trade and factor markets commuting and migration we find substantial heterogeneity across locations in local employment elasticities we show that this heterogeneity can be well explained with theoretically motivated measures of commuting flows without taking into account this dependence estimates of the local employment elasticity for one location are not generalizable to other locations we also find that commuting flows and their importance cannot be accounted for with standard measures of size or wages at the county or commuting zone levels

how regions react to recessions resilience and the role of economic structure martin r sunley p gardiner b and tyler p how regions react to recessions resilience and the role of economic structure regional studies this paper examines how employment in the major uk regions has reacted to the four major recessions of the last 40 years namely 1974 76 1979 83 1990 93 and 2008 10 the notions of resistance and recoverability are used to examine these reactions the analysis reveals both continuities and significant changes in the regional impact of recession from one economic cycle to the next further while economic structure is found to have exerted some influence on the resistance and recoverability of certain regions in general region specific or competitiveness effects appear to have played an equally if not more significant role

impact of introducing make to order options in a make to stock environment firms engaged in consumer product sales often implement a strict make to stock approach applying a single price to all customers in such systems customers can get the product at the given price upon availability on the shelf however consumers can often tolerate a delay between order placement and demand satisfaction under a price discount recognizing this phenomenon a supplier may consider offering a menu of delivery price options to consumers where longer delay time options imply lower prices demands from customers willing to wait provide advance demand information to the supplier this paper studies strategies to exploit this additional information to improve profitability and service levels primarily assuming that delivery times are set exogenously we determine optimal prices and stock levels under the new delayed demand satisfaction options in addition we develop analytical models to characterize the system performance gains under the new demand fulfillment option

a dynamic rationing policy for continuous review inventory systems stock rationing is an inventory policy that allows differential treatment of customer classes without using separate inventories in this paper we propose a dynamic rationing policy for continuous review inventory systems which utilizes the information on the status of the outstanding replenishment orders for both backordering and lost sales environments we conduct simulation studies to compare the performance of the dynamic policy with the static critical level and the common stock policies and quantify the gain obtained we propose two new bounds on the optimum dynamic rationing policy that enables us to tell how much of the potential gain the proposed dynamic policy realizes we discuss the conditions under which stock rationing both dynamic and static is beneficial and assess the value of the dynamic policy

knowledge flows externalities and innovation networks abstractknowledge flows externalities and innovation networks regional studies this editorial introduces the articles addressing the multifaceted and composite phenomenon of knowledge flows and externalities within innovation networks the papers offer a diversity of country contexts as well as analytical approaches and methods starting with methods they contain econometric analysis as well as social network analysis and combinations of the two while most of the papers use econometric analysis the level of analysis ranges from firm and individual level to aggregate analyses at the sectoral and regional level moreover patents are the main starting point but the proposed contributions show once more how different the approaches can be when using the same variables the country context is diverse and includes data sources from us and european regions

a make to stock system with multiple customer classes and batch ordering this paper examines the impact of customer order sizes on a make to stock system with multiple demand classes we first characterize the manufacturer s optimal production and rationing policies when the demand is nonunitary and lost if unsatisfied we also investigate the optimal policies of a backorder system with two demand classes and fixed order sizes through a numerical study we show the effects of batch orders on the manufacturer s inventory cost as well as on the benefit of optimal stock rationing it is shown that batch ordering may reduce the manufacturer s overall cost if carefully introduced in a first come first served fcfs system with the same effective demand rates the customers order sizes also have a strong impact on the benefit of optimal stock rationing

surviving the great recession the influence of income inequality in us urban counties abstractsurviving the great recession the influence of income inequality in us urban counties regional studies while there has been extensive research on the role of income inequality in economic growth there has been less investigation as to the role of income inequality on economic resilience this paper addresses the relationship between income inequality and resilience by evaluating the vulnerability of urban counties in the united states entering recession between 2006 and 2010 and tests whether income inequality contributes to their probability of recession survival a cox proportional hazards model is used to determine factors contributing toward urban counties resilience to the external shock of the great recession the research is focused on the relationship between the level of income inequality in a county and its recession risk it is found that areas with increased income inequality entered recession earlier

a spatial perspective on european integration heterogeneous welfare and migration effects from the single market and the brexit we use a quantitative model to study the implications of european integration for welfare and net migration flows across 1 280 european regions the model suggests that an increase of trade barriers to the level of 1957 reduces welfare by about 5 8 on average depending on the presumed trade elasticity however remote regions may face initial welfare losses of up to 10 these heterogeneous welfare effects cause estimated net migration of 1 9 of the population to the european geographic center implying that the dismantling of trade barriers in europe has led to a more homogeneous spatial distribution of economic activity with regard to the brexit we find moderate welfare losses for the united kingdom of 1 05 in the most pessimistic scenario while continental europe s welfare declines by 0 41 jel f15 r12 r13 r23

dynamic pricing through discounts for optimizing multiple class demand fulfillment in a multiple customer class model of demand fulfillment for a single item we consider the use of dynamic price discounts to encourage backlogging of demand for customer classes denied immediate service customers are assumed to arrive over several stages in a period and customer classes are distinguished by their contractual price and sensitivity to discounts through dynamic programming we determine the optimal discounts to offer assuming a linear model for the sensitivity of customers to such inducements we show that customers are served in class order and allocation of inventory to demand is determined by considering the current number of customers backlogged as well as the current inventory position through comparison to a naive supplier allocating inventory first come first served with no discounting we show that profits are primarily influenced by the allocation of capacity and the use of price discounts primarily benefits the second class customers overall fill rate heuristics for implementation of the solution in real time settings are given

comparative advantage and the welfare impact of european integration this paper investigates the welfare gains from european trade integration and the role of comparative advantage in determining the magnitude of those gains we use a multi sector ricardian model implemented on 79 countries and compare welfare in the 2000s to a counterfactual scenario in which east european countries are closed to trade for west european countries the mean welfare gain from trade integration with eastern europe is 0 16 ranging from zero for portugal to 0 4 for austria for east european countries gains from trade are 9 23 at the mean ranging from 2 85 for russia to 20 for estonia for eastern europe comparative advantage is a key determinant of the variation in the welfare gains countries whose comparative advantage is most similar to western europe tend to gain less while countries with technology most different from western europe gain the most andrei a levchenko and jing zhang

adjustment strategies for a fixed delivery contract we consider a long term contractual agreement between buyer and seller in whichq units are delivered to the buyer at regular time intervals it must be true that the delivery quantity q is less than the mean demand per period in order to manage the inventory the buyer has the option of adjusting the delivery quantity upwards just prior to a delivery but must pay a premium to do so demand is assumed random and we model the system in a continuous review setting we show that the equations one must solve to find optimal adjustment strategies are intractable a diffusion approximation is developed which when coupled with the solution to an even simpler deterministic version of the problem yields very simple but effective approximations extensive computations are included to compare the performance of the optimal and approximate policies we also empirically derive a formula for computingq whose accuracy is established computationally we prove that the fixed delivery contract results in lower variance of orders to the seller we also include a computational study to find the unit cost discount that equalizes the expected costs for the fixed delivery contract and the base stock contract for a large parameter set

education market rigidities and growth the paper exploits macro panel data for oecd countries close to the technological frontier the education level product market rigidities and employment protection legislation would be significantly related to tfp growth with a substantial contribution of the interaction between market rigidities

reduce shortage with self reservation policy for a manufacturer paying both fixed and variable stockout expenditure this study considers a single item make to stock system with continuous time production and inventory controls to meet bulk demand with an exponential inter arrival time a key issue in this system is the non convex shortage cost consisting of fixed and variable expenditures when the demand is not fully satisfied we propose a self reservation policy by building a markov decision process to minimize the overall cost we find that the optimal production control is still a base stock policy but the structure of the optimal self reservation policy is very complicated however if the effective outstanding variable shortage cost is sufficiently large the optimal self reservation policy has an easy form of reserve all or nothing our numerical examples indicate the optimal policy may reduce the total average cost by 47 on average

is labour rigidity harming europe s competitiveness the effect of job protection on the pattern of trade and welfare abstract we develop a model to analyse the implications of firing costs on international specialization to avoid paying the firing cost the country with a rigid labor market will tend to produce relatively secure goods at a late stage of their product life cycle an international product cycle emerges where new goods are first produced in the low firing cost country and then move to the high firing cost country an increase in firing costs in the high firing cost country lowers welfare there and increases welfare in the low firing cost country it also narrows the range of goods produced by the high firing cost country biasing its specialization towards more mature goods

prioritizing regular demand while reserving capacity for emergency demand abstract this research is motivated by the capacity allocation problem at a major provider of customized products to the oil and gas drilling industry we formulate a finite horizon discrete time dynamic programming model in which a firm decides how to reserve capacity for emergency demand and how to prioritize two classes of regular demand while regular demand can be backlogged emergency demand will be lost if not fulfilled within the period of its arrival since backlogging cost accumulates over time we find it optimal for the firm to adopt a dynamic prioritization policy that evaluates the priorities of different classes of regular demand every period the optimal prioritization involves metrics that measure backlogging losses from various perspectives we fully characterize the firm s optimal prioritization and reservation policy those characterizations shed light on managerial insights

the mismatch between local voting and the local economic consequences of brexit abstractthe mismatch between local voting and the local economic consequences of brexit regional studies this paper reveals that in the 2016 uk referendum regarding whether to remain in or leave the european union the regions that voted strongly for leave tended also to be those same regions with greatest levels of dependency on european union markets for their local economic development this observation flies in the face of pro leave narratives that posited that the major beneficiaries of european union membership were the metropolitan elites of london economic geography dominated the observed voting patterns and geography will also certainly dominate the post brexit economic impacts but not necessarily in a way that voters anticipated or wished for

employment growth and inter industry job reallocation spatial patterns and relatedness abstractemployment growth and inter industry job reallocation spatial patterns and relatedness regional studies the nature of employment reallocation between industries is assessed using rich register data for the netherlands it is found that employment decline in some industries is countered in a communicating vessels fashion by employment growth in other industries which is primarily driven by the availability of released skilled labour these labour demand interactions are predominantly local and stronger between related industries in addition the inter industry labour reallocation has a distinct geographical character in which the location of employment creation depends primarily on the residential location of the released employees rather than on the location of the job destruction

managing an available to promise assembly system with dynamic short term pseudo order forecast we study an order promising problem in a multiclass available to promise atp assembly system in the presence of pseudo orders a pseudo order refers to a tentative customer order whose attributes such as the likelihood of an actual order order quantity and confirmation timing can change dynamically over time a unit demand from any class is assembled from one manufactured unit and one inventory unit where the manufactured unit takes one unit of capacity and needs a single period to produce an accepted order must be filled before a positive delivery lead time the underlying order acceptance decisions involve trade offs between committing resources production capacity and component inventory to low reward firm orders and reserving resources for high reward orders we develop a markov chain model that captures the key characteristics of pseudo orders including demand lumpiness nonstationarity and volatility we then formulate a stochastic dynamic program for the atp assembly system that embeds the markov chain model as a short term forecast for pseudo orders we show that the optimal order acceptance policy is characterized by class prioritization resource imbalance based rationing and capacity inventory demand matching in particular the rationing level for each class is determined by a critical value that depends on the resource imbalance level defined as the net difference between the production capacity and component inventory levels extensive numerical tests underscore the importance of the key properties of the optimal policy and provide operational and managerial insights on the value of the short term demand forecast and the robustness of the optimal policy this paper was accepted by martin lariviere operations management

the erosion of colonial trade linkages after independence high trade between countries with colonial ties may be explained by government policies that establish preferential access or as a consequence of networks formed through social interactions using bilateral trade data from 1948 to 2003 we examine the eect of independence on post colonial trade the severing of formal colonial relations can lead to an immediate reduction in trade as preferential access is eliminated as well as a gradual reduction corresponding to the deterioration of trading networks our results reveal that independence reduces colonial trade with its colonizer metropole the reduction cumulates over a 30 year period and the disruption is particularly severe for hostile separations we also find that overall colonial trade falls subsequent to independence but to a lesser extent than trade with the metropole

optimal policies for inventory systems with priority demand classes we consider a periodic review inventory system with two priority demand classes one deterministic and the other stochastic the deterministic demand must be met immediately in each period however the units of stochastic demand that are not satisfied during the period when demand occurs are treated as lost sales at each decision epoch one has to decide not only whether an order should be placed and how much to order but also how much demand to fill from the stochastic source the firm has the option to ration inventory to the stochastic source i e not satisfy all customer demand even though there is inventory in the system we first characterize the structure of the optimal policy we show that in general the optimal order quantity and rationing policy are state dependent and do not have a simple structure we then propose a simple policy called s k s policy wheres ands ordering policy determine when and how much to order whilek rationing policy specifies how much of the stochastic demand to satisfy we report the results of a numerical study which shows that this simple policy works extremely well and is very easy to compute

optimal production and rationing policy of two stage tandem production system abstract the rationing literature has been so far oblivious to the fact that sellable items may not only be finished products but also intermediate products to manufacture subsequent sellable products we address this gap by considering an inventory rationing problem in a two product tandem make to stock production inventory system bulk demand arrives to a partial batch production system with exponentially distributed production time for each batch the management has to decide whether to run or stop production and whether the various classes of demand for both products intermediate product ip and finished product or end product ep have to be satisfied from available inventory or not in which case demand is lost in order to maximize the firm s expected profit we present the corresponding dynamic programming formulation and characterize the optimal policy the resulting policy depends on dynamic switching curves which define a thresholds to continue or discontinue production and b thresholds to satisfy or turn down incoming orders we identify the key value drivers and compare various heuristic policies through extensive numerical analyses

a threshold inventory rationing policy for service differentiated demand classes motivated by a study of the logistics systems used to manage consumable service parts for the u s military we consider a static threshold based rationing policy that is useful when pooling inventory across two demand classes characterized by different arrival rates and shortage stockout and delay costs the scheme operates as a q r policy with the following feature demands from both classes are filled on a first come first serve basis as long as on hand inventory lies above a threshold levelk once on hand inventory falls below this level low priority i e low shortage cost demand is backordered while high priority demand continues to be filled we analyze this static policy first under the assumption that backorders are filled according to a special threshold clearing mechanism structural results for the key performance measures are established to enable an efficient solution algorithm for computing stock control and rationing parameters i e q r andk numerical results confirm that the solution under this special threshold clearing mechanism closely approximates that of the priority clearing policy we next highlight conditions where our policy offers significant savings over traditional round up and separate stock policies encountered in the military and elsewhere finally we develop a lower bound on the cost of the optimal rationing policy numerical results show that the performance gap between our static threshold policy and the optimal policy is small in environments typical of the military and high technology industries

resilience revisited assessing the impact of the 2007 09 recession on 83 canadian regions with accompanying thoughts on an elusive concept dube j and polese m resilience revisited assessing the impact of the 2007 09 recession on 83 canadian regions with accompanying thoughts on an elusive concept regional studies viewing the 2007 09 recession as an exogenous shock the paper proposes an assessment of the resilience of 83 canadian regions using four standard metrics population employment unemployment and employment rates for each metric regions are evaluated on three posited dimensions of resilience resistance rebound and recuperation the results point to generally responsive regional economies with a range of reactions to the recessionary shock a priori compatible with the notion of resilience however the range of observed responses depending on metrics used methods applied and contextual considerations leaves much room for interpretation making it difficult to exclude players the assessment serves in turn as a laboratory for a reflection on resilience as a useful analytical concept in regional studies it is conc

inventory rationing in a make to stock production system with several demand classes and lost sales this paper considers the stock rationing problem of a single item make to stock production system with several demand classes and lost sales for the case of poisson demands and exponential production times we show that the optimal policy can be characterized by a sequence of monotone stock rationing levels for each demand class there exists a stock rationing level at or below which it is optimal to start rejecting the demand of this class in anticipation of future arrival of higher priority demands a simple queueing model is analyzed to compute the operating cost of a rationing policy in a numerical study we compare the optimal rationing policy with a first come first served policy to investigate the benefit of stock rationing under different operating conditions of the system

capacity management for contract manufacturing contract manufacturers sell capacity under different terms to different buyers in a common practice the supplier offers a market standard price and lead time combination for products listed in its catalog at the same time it strikes contracts with some high volume customers who require recurring delivery of a custom product at a short notice usually timed to meet the buyer s production schedule whereas the manufacturer is obligated to satisfy demand from these customers it can dynamically choose which transactional orders to accept in this paper we analyze two scenarios in the first scenario the manufacturer produces contractual orders on a make to order basis and in the second it maintains finished goods inventory for such orders at each decision epoch the manufacturer decides which transactional orders to accept to maximize its long run expected profit when contractual items are made to stock the manufacturer also chooses how much extra capacity to allocate to contractual items over and above what is needed to meet realized demand we establish the structure of the optimal policies and propose scalable heuristics when optimal policies are hard to compute implement our models are then used to study the effect of demand variability on the optimal profit we also show how the amount of capacity available relative to demand changes the desirability of serving either transactional only or both markets

just cause employment policies in the presence of worker adverse selection the free market may not lead to the efficient level of just cause employment protection if workers are heterogeneous any firm that switches to just cause will attract a disproportionate share of workers that provide low effort yet are difficult to dismiss with cause thus there is an externality concerning each firm s just cause policy if all firms had just cause policies then the efficiency gains of just cause might outweigh the burden of the undesirable workers nevertheless no single firm may find it in its interest to switch to just cause it is possible for laws that require just cause to increase efficiency

tear down this wall on the persistence of borders in trade why do borders still matter for economic activity the reunification of germany in 1990 provides a unique natural experiment for examining the effect of political borders on trade both in the cross section and over time with the fall of the berlin wall and the rapid formation of a political and economic union strong and strictly enforced administrative barriers to trade between east germany and west germany were eliminated completely within a very short period of time the evolution of intra german trade flows after reunification then provides new insights for both the globalization and border effects literatures our estimation results show a remarkable persistence in intra german trade patterns along the former east west border political integration is not rapidly followed by economic integration instead we estimate that it takes at least one generation between 33 and 40 years or more to remove the impact of political borders on trade this finding strongly suggests that border effects are neither statistical artefacts nor mainly driven by administrative or red tape barriers to trade but arise from economic fundamentals

a single product inventory model for multiple demand classes we consider a single product inventory system that serves multiple demand classes which differ in their shortage costs or service level requirements we assume a critical level control policy and a backorder clearing mechanism in which we treat a backorder for a lower priority class equivalent to a reserve stock shortfall for the higher priority class we show the equivalence between this inventory system and a serial inventory system based on this equivalence we develop a model for cost evaluation and optimization under the assumptions of poisson demand deterministic replenishment lead time and a continuous review q r policy with rationing we propose a computationally efficient heuristic and develop a bound on its performance we provide a numerical experiment to show the effectiveness of the heuristic and the value from a rationing policy finally we describe how to extend the model to permit service times and how to extend the model to a multi echelon setting

job security provisions and employment european countries have enacted various job security provisions over the last 30 years employers are required to pay workers on separation or to give advance notice of termination in anything less than a perfectly functioning market there are effects of the provisions on employment incumbents are more likely to retain their jobs but new workers are less likely to be hired an examination of the european data suggests that severance pay requirements reduce employment

labour work and regional resilience recent political and economic events have thrown into question several assumptions about how regional economies work and for whom for regional studies the result is a wave of policy relevant empi

dismissal costs and innovation empirical evidence suggests that dismissal costs are negatively associated with r d intensity across countries but positively within countries over time this evidence can be rationalized theoretically with a negative entry effect and a positive innovation effect for incumbent firms

yield and allocation management in a continuous make to stock system with demand upgrade substitution abstract yield management is crucial for high tech industries to reduce over production however it is very challenging for a manufacturer to make a yield decision under the circumstance of uncertain demand and stochastic product quality for example in semiconductor manufacturing industry products are produced in batches within certain production cycle time even if the same raw material is put into the production system the product qualities measured by performance usually are not identical due to random yield in the manufacturing process since products have overlapped performance specifications products of the same batch are classified into different classes according to their qualities at the allocation stage products with higher performance can substitute for demand for products with lower performance this type of production and allocation system can be specified as a make to stock system with single material multi products multi periods upward demand substitution under random yield and uncertain demands in order to maximize profit the manufacturer needs to decide on the optimal input material quantity and the optimal allocation policy the problem is formulated as a stochastic dynamic programming model because manufacturer s profit is affected by the allocation policies atp r allocation policy is proposed to help manufacturer make real time allocation decisions a numerical experiment shows that atp r allocation policy performs better than the traditional myopic allocation policy to reduce the computation burden involved in atp r allocation policy we further propose a simplified algorithm and our experimental studies provide proof of the effectiveness of the proposed simple algorithm

employment resilience in europe and the 2008 economic crisis insights from micro level data doran j and fingleton b employment resilience in europe and the 2008 economic crisis insights from micro level data regional studies this paper analyses employment resilience to the 2008 economic crisis using individual level data from the european social survey ess combined with nuts 1 regional economic statistics it models employment outcomes for individuals for 2002 08 and generates counterfactual outcomes for 2010 for individual level employment assuming there is no recession a resilience index based on the difference between employment outcomes assuming actual economic conditions and a no recession counterfactual is generated resilience varies substantially and is higher in german and french regions than in peripheral regions highly educated individuals middle aged individuals unionized workers and men are more resilient

which types of relatedness matter in regional growth industry occupation and education abstractwhich types of relatedness matter in regional growth industry occupation and education regional studies this paper provides a conceptual discussion of relatedness which suggests a focus on individuals as a complement to firms and industries the empirical relevance of the main arguments is tested by estimating the effects of related and unrelated variety in education and occupation among employees as well as in industries on regional growth the results show that occupational and educational related variety are positively correlated with productivity growth which supports the conceptual discussion put forth in the paper in addition related variety in industries is found to be negative for productivity growth but positive for employment growth

inventory policies for systems with stochastic and deterministic demand we consider a periodic review inventory system with demand arriving simultaneously from a deterministic source and a random source the deterministic demand has to be satisfied immediately and the stochastic demand can be backordered assuming that the stochastic demand is never backlogged if there is stock in the system we prove that a modified s s policy is optimal under general conditions if there is a setup cost if there is a smoothing cost instead of the setup cost we observe that the problem corresponds to a standard model with one source of demand

using imperfect advance demand information in ordering and rationing decisions in this paper we consider an inventory problem with two demand classes having different priorities the appropriate policy of rationing the available stock i e reserving some stock for meeting prospective future demand of preferred customers at the expense of deliberately losing some of the currently materialized demand of lower demand class es relies on the estimation of the future demand utilizing current signals on future demand which we refer to as imperfect advance demand information adi decreases uncertainty on future demand and may help to make better decisions on when to start rejecting lower class demand we develop a model that incorporates imperfect adi with inventory ordering replenishment decision and rationing available stock in a two period setting we show some structural properties solve the rationing problem and propose solution methods based on monte carlo simulation for the ordering problem we conduct numerical tests to measure the impact of system parameters on the expected value of imperfect adi and provide useful managerial insights

returning to work regional determinants of re employment after major redundancies abstractusing matched employer employee data on roughly 429 000 workers made redundant from large plant closures or major downsizing in sweden between 1990 and 2005 this paper analyses the role of the regional industry mix specialization related and unrelated variety in the likelihood of returning to work the results show that a high presence of same or related industries speeds up the re employment process while high concentrations of unrelated activities do not the role of related activities is particularly evident in the short run and in regions with high unemployment consequently the prospect of successful diversification is enhanced in regions with related industries

inventory sharing and rationing in decentralized dealer networks an increasing number of manufacturers have started to pursue a strategy that promotes inventory sharing among the dealers in their distribution network in this paper we analyze a decentralized dealer network in which each independent dealer is given the flexibility to share his inventory we model inventory sharing as a multiple demand classes problem in which each dealer faces his own customer demand with high priority and inventory sharing requests from other dealers with low priority assuming that each dealer uses a base stock and threshold rationing policy for his inventory stocking and inventory sharing decisions we explicitly model the interactions between the dealers through inventory sharing and obtain aclosed form cost function for each dealer based on the steady state distribution of the inventory levels at the two dealers we then provide a detailed supermodularity analysis of the inventory sharing and inventory rationing game in which each dealer has a two dimensional strategy set stocking level and rationing level we show that the full sharing game in which dealers precommit to sharing all of their on hand inventory and the fixed sharing level game in which dealers precommit to sharing a portion of their on hand inventory are supermodular and thus a pure strategy nash equilibrium is guaranteed to exist for the rationing game in which dealers precommit to their stocking levels we show that there exists a dominant strategy equilibrium on the dealers sharing rationing levels finally a comprehensive computational study is conducted to highlight the impact of the manufacturer s incentives subsidies and or transshipment fees on the dealers sharing behavior

a hybrid inventory policy with split delivery under regular and surge demand abstract this paper proposes a hybrid inventory policy with split delivery under regular and surge demand the combination of regular and surge demand can be observed in many areas such as healthcare inventory and humanitarian supply chain management the arrival rate of regular demand is typically higher than the arrival rate of surge demand whereas the volume of regular demand is typically lower than the volume of surge demand this paper proposes an inventory management model that considers both emergency and regular replenishments corresponding to both demand patterns the equilibrium equations developed for this model are based on the level crossing theory these equations are used to develop a search based heuristics to identify near optimal inventory management policies numerical results show that the proposed hybrid inventory policy with split delivery outperforms similar hybrid inventory policy without split delivery when holding and shortage costs are relatively low

dynamic inventory rationing strategies for inventory systems with two demand classes poisson demand and backordering we study inventory systems with two demand classes critical and non critical poisson demand and backordering we analyze dynamic rationing strategies where the number of items reserved for critical demand depends on the remaining time until the next order arrives different from results in the literature we do not discretize demand but derive a set of formulae that determine the optimal rationing level for any possible value of the remaining time moreover we show that the cost parameters can be captured in a single relevant dimension which allows us to present the optimal rationing levels in charts and lookup tables that are easy to implement numerical examples illustrate that the optimal dynamic rationing strategy outperforms all static strategies with fixed rationing levels