Model

MAGNET stands for the Modular Applied GeNeral Equilibrium Tool. It is a global computable general equilibrium model, which can be flexibly tailored to specific research questions at hand and regions and products of interest. MAGNET is the successor of the LEITAP model extensively used in policy analyses in the past. Both LEITAP and MAGNET are based on the standard GTAP model. The core of MAGNET is the GTAP model, to which multiple adaptions and extensions have been added, including those listed below. Noteworthy, MAGNET is compatible with both GTAPv6 and GTAPv7.

  • Differences in substitutability of land between sectors
  • Imperfect mobility of labor between agricultural and non-agricultural sectors
  • Output quotas for milk and sugar
  • Endogenous land supply
  • Biofuel sectors (1st and 2nd generation) and the biofuel directive
  • Modulation of the EU common agricultural policy from first to second pillar measures
  • Income elasticities dependent on GDP per capita
  • International capital mobility for dynamic analyses
  • Nutrition indicators
  • Household food security indicators
  • Circularity module: municipal solid waste flows and treatment options
  • Aquaculture and seaweed sectors
  • Endogenous natural resource stocks
  • Emission permit trading and mac curves, luluc emissions
  • Climate damage assessment
  • Adaptions for investments, bilateral tariff rate quota, alternative consumption functions etc.

The Foundation of MAGNET: GTAP Core

The standard GTAP model (Version 6.2 of September 2003) was the starting point for developing MAGNET. GTAP is a general equilibrium model covering all sectors of the economy (agriculture, manufacturing and services) in contrast to partial equilibrium models, which focus on subsets of an economy. GTAP is a global model, covering all regions and major countries in the world. A region may include several countries for which there is no individual country data.

Figure 1: MAGNET – an economic model of nations in the global economy MAGNET

In the GTAP model, the regional household supplies factors (i.e. land, skilled and unskilled labour, capital and natural resources) to the production sectors. By combining these factors with intermediate inputs from other sectors, commodities are produced. Produced commodities are either supplied to domestic markets to satisfy the demand for commodities by private households and governments or they are exported.

For every region in the model there is a single representative household demanding consumption goods (including savings) on the behalf of the private household and the government. Total demand is determined by income earned by land, labour and capital as well as income from taxes. The demand for goods can be met by national producers or by imports. Each commodity is produced by one sector, while each sector produces only one commodity. For each sector there is a single producer, i.e. there is one producer of wheat, one for gas, one for wood products, etc.

The model includes trade between all regions in the model and accounts for trade barriers between regions via tariffs. These tariffs may drive a wedge between prices in regions, i.e. the same product may be more expensive in one region than in another because of tariffs. Whereas international trade is modelled by tracing all bilateral flows, international capital flows are governed by a global bank. This bank collects savings and uses them for international investments. Since savings are pooled by the global bank before being used for investments, it is not possible to trace bilateral capital flows.

Prices of goods and of land, labour and capital in each region adjust to assure that both national and international demand and supply are equal, hence the term general equilibrium model. Thus, when a policy simulation is run, for example to analyze the impacts of lowering tariffs between regions, the model computes by sector the production, consumption and trade (both imports and exports) as well as price levels that result in equilibrium in national and international markets.

More information on the standard GTAP model can be found on the GTAP website.

MAGNET Philosophy

The development of MAGNET has been driven by the following key principles:

  • A modular set-up around a GTAP core: the modular set-up has been designed such that all model extensions can be switched on through choices in a single parameter file, sometimes in combination with changes in closure file. This allows new users to start with GTAP and then add extensions as needed. For experienced users it facilitates the tailoring of the model structure to the research question at hand, and eases debugging when developing the model. The GTAP model was chosen as a starting point because it is a widely used CGE model and the associated GTAP network provides a common background which enables comparison with a wide variety of other CGE models developed from the GTAP model.

  • The GTAP core is kept intact with only minimal changes. A notable change is the introduction of a distinction between production sectors and produced commodities throughout the model to introduce by-products. Data are kept and processed at the lowest level of detail to allow the user to aggregate the GTAP regions into groups that are relevant for the research question. All databases are kept as provided by their original sources and processed at the lowest level of detail.

  • All data changes and adjustments are coded in GEMPACK to enhance tractability and quality control. In addition, this approach facilitates the updating of datasets since the same code can be applied to the updates.

MAGNET Regions and Countries

MAGNET covers 141 regions and countries (table 1). Currently (2020), MAGNET is based on Version 10 of the GTAP database.

Table 1: MAGNET countries and regions

Country numberCountry nameCountry numberCountry nameCountry numberCountry name
1Australia48Rest of Central America95Armenia
2New Zealand49Dominican Republic96Azerbaijan
3Rest of Oceania50Jamaica97Georgia
4China51Puerto Rico98Bahrain
5Hong Kong52Trinidad and Tobago99Iran Islamic Republic of
6Japan53Caribbean100Israel
7Korea Republic of54Austria101Kuwait
8Mongolia55Belgium102Jordan
9Taiwan56Bulgaria103Oman
10Rest of East Asia57Croatia104Qatar
11Brunei Darussalam58Cyprus105Saudi Arabia
12Cambodia59Czech Republic106Turkey
13Indonesia60Denmark107United Arab Emirates
14Lao People’s Democratic Republic61Estonia108Rest of Western Asia
15Malaysia62Finland109Egypt
16Philippines63France110Morocco
17Singapore64Germany111Tunisia
18Thailand65Greece112Rest of North Africa
19Viet Nam66Hungary113Benin
20Rest of Southeast Asia67Ireland114Burkina Faso
21Bangladesh68Italy115Cameroon
22India69Latvia116Cote d’Ivoire
23Nepal70Lithuania117Ghana
24Pakistan71Luxembourg118Guinea
25Sri Lanka72Malta119Nigeria
26Rest of South Asia73Netherlands120Senegal
27Canada74Poland121Togo
28United States of America75Portugal122Rest of Western Africa
29Mexico76Romania123Central Africa
30Rest of North America77Slovakia124South Central Africa
31Argentina78Slovenia125Ethiopia
32Bolivia, Plurinational State of79Spain126Kenya
33Brazil80Sweden127Madagascar
34Chile81United Kingdom128Malawi
35Colombia82Switzerland129Mauritius
36Ecuador83Norway130Mozambique
37Paraguay84Rest of EFTA131Rwanda
38Peru85Albania132Tanzania United Republic of
39Uruguay86Belarus133Uganda
40Venezuela87Russian Federation134Zambia
41Rest of South America88Ukraine135Zimbabwe
42Costa Rica89Rest of Eastern Europe136Rest of Eastern Africa
43Guatemala90Rest of Europe137Botswana
44Honduras91Kazakhstan138Namibia
45Nicaragua92Kyrgyzstan139South Africa
46Panama93Tajikistan140Rest of South African Customs
47El Salvador94Rest of Former Soviet Union141Rest of the World

MAGNET Sectors and Commodities

MAGNET covers 113 sectors and 127 commodities (table 2). Currently (2020), MAGNET is based on Version 10 of the GTAP database.

Table 2: MAGNET and GTAP sectors/commodities

NumberNameNumberNameNumberName
1Paddy rice23Processed rice45Manufactures nec
2Wheat24Sugar46Electricity
3Cereal grains nec25Food products nec47Gas manufacture, distribution
4Vegetables, fruit, nuts26Beverages and tobacco products48Water
5Oil seeds27Textiles49Construction
6Sugar cane, sugar beet28Wearing apparel50Trade
7Plant-based fibers29Leather products51Accommodation, Food and service
8Crops nec30Wood products52Transport nec
9Bovine cattle, sheep and goats31Paper products, publishing53Water transport
10Animal products nec32Petroleum, coal products54Air transport
11Raw milk33Chemical products55Warehousing and support activities
12Wool, silk-worm cocoons34Basic pharmaceutical products56Communication
13Forestry35Rubber and plastic products57Financial services nec
14Fishing36Mineral products nec58Insurance
15Coal37Ferrous metals59Real estate activities
16Oil38Metals nec60Business services nec
17Gas39Metal products61Recreational and other service
18Minerals nec40Computer, electronic and optic62Public Administration and defe
19Bovine meat products41Electrical equipment63Education
20Meat products nec42Machinery and equipment nec64Human health and social work a
21Vegetable oils and fats43Motor vehicles and parts65Dwellings
22Dairy products44Transport equipment nec

Table 3: Additional MAGNET sectors/commodities

NumberNameNumberNameNumberName
66Animal feed82Mixed fossil biochemical sector98Crustaceans
67Crude vegetable oil83Electricity from coal99Marine fish
68Biogasoline84Electricity from gas100Molusks
69Biodiesel85Electricty from nuclear101Fish processing
70Fertilizer nutrient n86Electricty from hydro102Bioplastics
71Fertilizer nutrient p87Electricty from wind and solar103Fossil kerosine
72Fertilizer nutrient k88Bioelectricity 2nd gen104Biokerosine
73Biofuel feedstock grains89Residue sector105Waste Collection rest waste
74Biofuel feedstock sugar90Pellet sector106Waste collection green waste
75Biofuel feedstock molasse91Plantation107Composting
76Biofuel feedstock oils92Poultry live animals108Incineration
77Ftfuel 2nd gen biofuel93Poultry meat109Landfilling
78Ethanol 2nd gen biofuels94Beef cattle110Waste collection glass paper
79Ligno sugar95Beaf meat111Recycling
80Pe biochemical96Diadromis fish112Heat
81Pla biochemical97Fresh water fish113Bioheat
114Seaweed

Table 4: Additional MAGNET commodities - byproducts

NumberName
114DDGS: byproduct of Biogasoline sector
115Molasse: buproduct of Sugar sector
116Oil cake: byproduct of Crude vegetable oil sector
117Residue pdr: byproduct of Paddy rice sector
118Residue wheat: byproduct of Wheat sector
119Residue gro**:** byproduct of Cereal grains nec sector
120Residue osd: byproduct of Oil seeds sector
121Residue ocr: byproduct of Cereal grains nec sector
122Residue frs: byproduct of Forestry sector
123Residue v_f: byproduct of Vegetables, fruit, nuts sector
124Fish meal: byproduct of Fish processing sector
125Biomass: byproduct of Composting sector
126Recycled paper and glass: byproduct of Recycling sector
127Energy from waste: byproduct of Incineration sector

Software and System Requirements

Requirements for running the entire MAGNET system include the following:

  • Software licenses for GEMPACK, INTEL FORTRAN Compiler 11 (64 bit)
  • Data licenses for at least one GTAP database, use of specific modules may require additional database licenses
  • 64 bit machine with at least 16 GB RAM
  • For DSS (the modelling interface) .Net 4.0 is required; can be freely downloaded, but must be installed
  • GTREE (the code viewer and editor) must be installed, available for free on request
  • Preferably an SVN server is available; for easy tracking of adjustments made to data and programs and updating to new versions of MAGNET.