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on Computational Economics |
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Issue of 2012‒03‒08
seven papers chosen by |
| By: | Marianna De Santis (Dipartimento di Informatica e Sistemistica "Antonio Ruberti" Sapienza, Universita' di Roma); Stefano Lucidi (Dipartimento di Informatica e Sistemistica "Antonio Ruberti" Sapienza, Universita' di Roma); Francesco Rinaldi (Dipartimento di Informatica e Sistemistica "Antonio Ruberti" Sapienza, Universita' di Roma) |
| Abstract: | Mixed-Integer optimization is a powerful tool for modeling many optimization problems arising from real-world applications. Finding a rst feasible solution represents the rst step for several MIP solvers. The Feasibility pump is a heuristic for nding feasible solutions to mixed integer linear problems which is eective even when dealing with hard MIP instances. In this work, we start by interpreting the Feasibility Pump as a Frank-Wolfe method applied to a nonsmooth concave merit function. Then, we dene a general class of functions that can be included in the Feasibility Pump scheme for measuring solution integrality and we identify some merit functions belonging to this class. We further extend our approach by dynamically combining two dierent merit functions. Finally, we dene a new version of the Feasibility Pump algorithm, which includes the original version of the Feasibility Pump as a special case, and we present computational results on binary MILP problems showing the eectiveness of our approach. |
| Keywords: | Mixed integer programming; Concave penalty functions; Frank-Wolfe algorithm; Feasibility Problem |
| Date: | 2011 |
| URL: | http://d.repec.org/n?u=RePEc:aeg:wpaper:2011-8&r=cmp |
| By: | Francesco Bosello (Fondazione Eni Enrico Mattei, University of Milan and Euro-Mediterranean Center for Climate Change); Fabio Eboli (Fondazione Eni Enrico Mattei and Euro-Mediterranean Center for Climate Change); Roberta Pierfederici (Fondazione Eni Enrico Mattei and Euro-Mediterranean Center for Climate Change) |
| Abstract: | The present research describes a climate change integrated impact assessment exercise, whose economic evaluation is based on a CGE approach and modeling effort. Input to the CGE model comes from a wide although still partial set of up-to-date bottom-up impact studies. Estimates indicate that a temperature increase of 1.92°C compared to pre-industrial levels in 2050 could lead to global GDP losses of approximately 0.5% compared to a hypothetical scenario where no climate change is assumed to occur. Northern Europe is expected to benefit from the evaluated temperature increase (+0.18%), while Southern and Eastern Europe are expected to suffer from the climate change scenario under analysis (-0.15% and -0.21% respectively). Most vulnerable countries are the less developed regions, such as South Asia, South-East Asia, North Africa and Sub-Saharan Africa. In these regions the most exposed sector is agriculture, and the impact on crop productivity is by far the most important source of damages. It is worth noting that the general equilibrium estimates tend to be lower, in absolute terms, than the bottom-up, partial equilibrium estimates. The difference is to be attributed to the effect of market-driven adaptation. This partly reduces the direct impacts of temperature increases, leading to lower damage estimates. Nonetheless these remain positive and substantive in some regions. Accordingly, market-driven adaptation cannot be the solution to the climate change problem. |
| Keywords: | Computable General Equilibrium Modeling, Impact Assessment, Climate Change |
| JEL: | C68 Q51 Q54 |
| Date: | 2012–02 |
| URL: | http://d.repec.org/n?u=RePEc:fem:femwpa:2012.02&r=cmp |
| By: | Adamos Adamou; Sofronis Clerides; Theodoros Zachariadis |
| Abstract: | Vehicle taxation based on CO2 emissions is increasingly being adopted worldwide in order to shift consumer purchases to low-carbon cars, yet little is known about the effectiveness and overall economic impact of these schemes. We focus on feebate schemes, which impose a fee on high-carbon vehicles and give a rebate to purchasers of low-carbon automobiles. We estimate a discrete choice model of demand for automobiles in Germany and simulate the impact of alternative feebate schemes on emissions, consumer welfare, public revenues and firm profits. The analysis shows that a well-designed scheme can lead to emission reductions without reducing overall welfare. |
| Keywords: | CO2 emissions, German automobile market, feebates, carbon taxation |
| Date: | 2012–01 |
| URL: | http://d.repec.org/n?u=RePEc:ucy:cypeua:01-2012&r=cmp |
| By: | Matias Holte (SINTEF ICT, Norway Dept. of Applied Mathematics); Carlo Mannino (Dipartimento di Informatica e Sistemistica "Antonio Ruberti" Sapienza, Universita' di Roma) |
| Abstract: | A general problem in health-care consists in allocating some scarce medical resource, such as operating rooms or medical staff, to medical specialties in order to keep the queue of patients as short as possible. A major difficulty stems from the fact that such an allocation must be established several months in advance, whereas the exact number of patients for each specialty is an uncertain parameter. Another problem arises for cyclic schedules, where the allocation is defined over a short period, e.g. a week, and then repeated during the time horizon. Even if the demand is perfectly known in advance, the number of patients may vary from week to week. We model both the uncertain and the cyclic allocation problem as adjustable robust scheduling problems. We develop a row and column generation algorithm to solve this problem: this turns out to be the implementor/adversarial algorithm for robust optimization recently introduced by Bienstock for portfolio selection. We apply our general model to compute master surgery schedules for a real-life instance from a large hospital in Oslo. |
| Keywords: | Health-care optimization, Master surgery scheduling, Robust optimization, Mixed-integer programming |
| Date: | 2011 |
| URL: | http://d.repec.org/n?u=RePEc:aeg:wpaper:2011-3&r=cmp |
| By: | Francesco Bosello (Fondazione Eni Enrico Mattei, University of Milan and Euro-Mediterranean Center for Climate Change); Fabio Eboli (Fondazione Eni Enrico Mattei and Euro-Mediterranean Center for Climate Change); Roberta Pierfederici (Fondazione Eni Enrico Mattei and Euro-Mediterranean Center for Climate Change) |
| Abstract: | The present research describes a climate change integrated impact assessment exercise, whose economic evaluation is based on a CGE approach and modeling effort. Input to the CGE model comes from a wide although still partial set of up-to-date bottom-up impact studies. Estimates indicate that a temperature increase of 1.92°C compared to pre-industrial levels in 2050 could lead to global GDP losses of approximately 0.5% compared to a hypothetical scenario where no climate change is assumed to occur. Northern Europe is expected to benefit from the evaluated temperature increase (+0.18%), while Southern and Eastern Europe are expected to suffer from the climate change scenario under analysis (-0.15% and -0.21% respectively). Most vulnerable countries are the less developed regions, such as South Asia, South-East Asia, North Africa and Sub-Saharan Africa. In these regions the most exposed sector is agriculture, and the impact on crop productivity is by far the most important source of damages. It is worth noting that the general equilibrium estimates tend to be lower, in absolute terms, than the bottom-up, partial equilibrium estimates. The difference is to be attributed to the effect of market-driven adaptation. This partly reduces the direct impacts of temperature increases, leading to lower damage estimates. Nonetheless these remain positive and substantive in some regions. Accordingly, market-driven adaptation cannot be the solution to the climate change problem. |
| Keywords: | Environmental Innovation, Industrial Sectors, ETS, Innovation Drivers, CIS Data |
| Date: | 2012–01 |
| URL: | http://d.repec.org/n?u=RePEc:fem:femwpa:2012.03&r=cmp |
| By: | Arita, Shawn; Tanaka, Kiyoyasu |
| Abstract: | During the past decade of declining FDI barriers, small domestic firms disproportionately contracted while large multinational firms experienced a substantial growth in Japan’s manufacturing sector. This paper quantitatively assesses the impact of FDI globalization on intra-industry reallocations and aggregate productivity. We calibrate the firm-heterogeneity model of Eaton, Kortum, and Kramarz (2011) to micro-level data on Japanese multinational firms. Estimating the structural parameters of the model, we demonstrate that the model can strongly replicate the entry and sales patterns of Japanese multinationals. Counterfactual simulations show that declining FDI barriers lead to a disproportionate expansion of foreign production by more efficient firms relative to less efficient firms. A hypothetical 20% reduction in FDI barriers is found to generate a 30.7% improvement in aggregate productivity through market-share reallocation. |
| Keywords: | Japan, International business enterprises, Foreign investments, Manufacturing industries, Industrial management, Multinational firms, FDI, Firm heterogeneity, Investment Liberalization |
| JEL: | F10 F23 L23 R12 R30 L25 |
| Date: | 2012–02 |
| URL: | http://d.repec.org/n?u=RePEc:jet:dpaper:dpaper324&r=cmp |
| By: | Broberg, Thomas (National Institute of Economic Research); Forsfält, Tomas (National Institute of Economic Research); Östblom, Göran (National Institute of Economic Research) |
| Abstract: | From the perspective of climate policy, a target for energy efficiency could imply costly overlapping regulation. We estimate, using a computable general equilibrium model of the Swedish economy, the potential economic cost of attaining the national 2020 energy intensity target by means of tax policy instruments. Our analysis shows that the efforts to meet the energy intensity target will also reduce carbon dioxide emissions, but at excessive costs compared to alternative climate policy instruments. Moreover, attainment of the energy intensity target will call for policy instruments additional to those needed for fulfilling the national climate policy target. The results are sensitive to the development of the nuclear energy production as the definition of energy intensity includes conversion losses in electricity production |
| Keywords: | climate policy; energy efficiency; carbon tax; overlapping regulation; general equilibrium; Sweden |
| Date: | 2011–06–01 |
| URL: | http://d.repec.org/n?u=RePEc:hhs:nierwp:0123&r=cmp |