The calculation of dynamic ecological footprint on the basis of the dynamic input-output model

The Leontief input-output model is widely used to determine the ecological footprint of consumption in a region or a country. It is able to capture spillover environmental effects along the supply change, thus its popularity is increasing in ecology related economic research. These studies are static and the dynamic investigations are neglected. The dynamic Leontief model makes it possible to involve the capital and inventory investment in the footprint calculation that projects future growth of GDP and environmental impacts. We show a new calculation method to determine the effect of capital accumulation on ecological footprint. Keywords: Dynamic Leontief model, Dynamic ecological footprint, Environmental management, Allocation metho

Solving a Production and Inventory Model with a Minimum Lot Size Constrain

The paper deals with the analysis of a special dynamic production and inventory model. In this model logical restrictions to fulfill an accepted constant minimal level of the production lot size are incorporated, instead of keeping setup cost in the objective function, as it is common in many other models. Detailed optimality conditions are derived, which make possible the application of a simple dynamic programming recursion procedure. --dynamic production-inventory model,minimum lot size,dynamic programming

Market Power with Dynamic Inventory Constraints: The Bias in Standard Measures

This paper incorporates inventory dynamics into an analysis of market power. Using a model in which each firm accounts for the effect of its current action on the current and future actions of itself and its competitors, we show that measures of market power that ignore inventory dynamics are biased. We then apply the model to the beef-packing industry using annual data on cattle stocks, slaughter and prices from 1933-1999. Our estimates suggest that static measures overestimate the amount of market power exerted by beef-packing firms.market power dynamic cattle conjectural variations stock

Modeling inventories over the business cycle.

We search for useful models of aggregate fluctuations with inventories. We focus exclusively on dynamic stochastic general equilibrium models that endogenously give rise to inventory investment and evaluate two leading candidates: the (S,s) model and the stockout avoidance model. Each model is examined under both technology shocks and preference shocks, and its performance gauged by its ability to explain the observed magnitude of inventories in the U.S. economy, alongside other empirical regularities, such as the procyclicality of inventory investment and its positive correlation with sales. We find that the (S,s) model is far more consistent with the behavior of aggregate inventories in the postwar U.S. when aggregate fluctuations arise from technology, rather than preference, shocks. The converse is true for the stockout avoidance model. Overall, while the (S,s) model performs well with respect to the inventory facts and other business cycle regularities, the stockout avoidance model does not. There, the essential motive for stocks is insufficient to generate inventory holdings near the data without destroying the model’s performance along other important margins. Finally, the stockout avoidance model appears incapable of sustaining inventories alongside capital. This suggests a fundamental problem in using reduced-form inventory models with stocks rationalized by this motiveInventories ; Business cycles

Modeling Inventories Over the Business Cycle

We search for useful models of aggregate fluctuations with inventories. We focus exclusively on dynamic stochastic general equilibrium models that endogenously give rise to inventory investment and evaluate two leading candidates: the (S,s) model and the stockout avoidance model. Each model is examined under both technology shocks and preference shocks, and its performance gauged by its ability to explain the observed magnitude of inventories in the U.S. economy, alongside other empirical regularities such as the procyclicality of inventory investment and its positive correlation with sales. We find that the (S,s) model is far more consistent with the behavior of aggregate inventories in the postwar U.S. when aggregate fluctuations arise from technology, rather than preference, shocks. The converse is true for the stockout avoidance model. Overall, while the (S,s) model performs well with respect to the inventory facts and other business cycle regularities, the stockout avoidance model does not. There, the essential motive for stocks is insufficient to generate inventory holdings near the data without destroying the model's performance along other important margins. Finally, the stockout avoidance model appears incapable of sustaining inventories alongside capital. This suggests a fundamental problem in using reduced-form inventory models with stocks rationalized by this motive.

The Equilibrium Dynamics for an Endogeneous Bid-Ask Spread in a Monopolistic financial Market

This paper presents an endogeneous model for the stochastic dynamics of the bid-ask spread of prices of nancial assets. The model is derived introducing an intermediary and inventory costs in the setting of equilibrium financial markets as described by Platen and Rebolledo (1996)Bid-ask spread; intermediary; dynamic equilibrium

Inventories and the Propagation of Sectoral Shocks

This paper studies the dynamic properties of an imperfectly competitive economy with inventory holdings. In particular, we focus on the serial correlation in aggregate output and employment produced by the holding of inventories in one sector of the economy and the co-movement between sectors of an economy over the cycle resulting from demand linkages. This model is then contrasted with a simple, competitive real business cycle model with inventories. We find that the predictions of these models with regards to the co-movement of employment may differ. Based on this, we present empirical evidence on the co-movement of employment over the business cycle which is consistent with the predictions of the model of imperfect competition with inventory holdings and demand linkages.

Inventories and the Stockout Constraint in General Equilibrium

We study the implications of a stockout constraint in a dynamic general equilibrium model, which can explain both standard business cycle and inventory facts. Under this constraint, inventories and demand are complements in generating sales, and hence the optimal level of inventories increases in expected demand. We show that the inventory to sales ratio is both persistent and countercyclical because the cost of carrying inventories is mainly determined by the interest rate. We use this model to disentangle output and sales, by matching the key inventory moments, and find that preference and productivity shocks are equally important in the data. Finally, we assess whether improvements in inventory management can explain the Great Moderation. We find that, although improvements in inventory management can reduce the need for inventory holdings, which decreases output volatility relative to sales volatility, lower levels of inventories actually increases sales volatility. Because these two effects offset each other, a change in inventory management does not change output volatility to any great extent