{"type":"script","doc_desc":{"producers":[{"name":"Reproducibility WBG","abbr":"DECDI","affiliation":"World Bank - Development Impact Department","role":"Verification and preparation of metadata"}],"prod_date":"2026-03-20","version":"1"},"project_desc":{"authoring_entity":[{"name":"Erhan Artuc","affiliation":"World Bank","email":"eartuc@worldbank.org"},{"name":"Johan Ortega","affiliation":"World Bank","email":"jortegahernandez@worldbank.org"}],"title_statement":{"title":"Reproducibility package for International Trade Policy And Quantitative Models: A Practitioner\u2019s Guide","idno":"RR_WLD_2026_593"},"data_statement":"Some data is restricted and has not been included in the reproducibility package. For more details, please refer to the README file. ","software":[{"name":"R","version":"4.5"},{"name":"Python","version":"3.9"},{"name":"MatLab","version":"2024b"},{"name":"Julia","version":"1.12.5"}],"scripts":[{"title":"Reproducibility package for International Trade Policy And Quantitative Models:\nA Practitioner\u2019s Guide","date":"2026-03","notes":"Computational reproducibility verified by Development Impact (DECDI) Analytics team, World Bank.","instructions":"See README in reproducibility package.","file_name":"RR_WLD_2026_593","zip_package":"RR_WLD_2026_593.zip","dependencies":"Python dependencies are stored in requirements.txt; Julia dependencies are stored in Project.toml. "}],"repository_uri":[{"name":"Reproducible Research Repository (World Bank)","uri":"https:\/\/reproducibility.worldbank.org"}],"production_date":"2026-03-20","abstract":"Quantitative international trade models are essential tools for policy analysis. This paper provides guidance for quantifying and solving trade models for policy simulations using popular programming languages, Python, Julia, Matlab and R. The solution follows simple linear steps and can easily be modified to add different components, thus be extended to a wide class of  models. Using the provided tools, the paper shows that an additional 25 percent ad valorem tariff between high and low income countries has a substantial negative effect on disposable income in all countries, ranging between 0.5% to 7.4%.","geographic_units":[{"name":"World","code":"WLD"}],"keywords":[{"name":"International Trade"},{"name":"International Trade Policy"}],"topics":[{"id":"F11","uri":"https:\/\/www.aeaweb.org\/econlit\/jelCodes.php?view=jel","vocabulary":"Journal of Economic Literature (JEL)","name":"Neoclassical Models of Trade","parent_id":"F1"},{"id":"F13","uri":"https:\/\/www.aeaweb.org\/econlit\/jelCodes.php?view=jel","vocabulary":"Journal of Economic Literature (JEL)","name":"Trade Policy \u2022 International Trade Organizations","parent_id":"F1"}],"output":[{"type":"Working Paper","description":"Policy Research Working Papers (PRWP) 11347","title":"International Trade Policy And Quantitative Models:\nA Practitioner\u2019s Guide","uri":"http:\/\/documents.worldbank.org\/curated\/en\/099455303302627347"}],"language":[{"name":"English","code":"EN"}],"technology_requirements":"Runtime: 10 minutes","disclaimer":"The materials in the reproducibility packages are distributed as they were prepared by the staff of the International Bank for Reconstruction and Development\/The World Bank. The findings, interpretations, and conclusions expressed in this event do not necessarily reflect the views of the World Bank, the Executive Directors of the World Bank, or the governments they represent. The World Bank does not guarantee the accuracy of the materials included in the reproducibility package.","license":[{"name":"Modified BSD3","uri":"https:\/\/opensource.org\/license\/bsd-3-clause\/"}],"contacts":[{"name":"Erhan Artuc","affiliation":"World Bank","email":"eartuc@worldbank.org"},{"name":"Reproducibility WBG","affiliation":"World Bank","email":"reproducibility@worldbank.org"}],"datasets":[{"name":"Inter-Country Input-Output tables (ICIO)","note":"There are two versions of ICIO: regular ICIO and extended ICIO. Authors use the 2025 edition (January 2026 update of regular ICIO). For this analysis, the authors use the latest year available: 2022. \nFile location \"data_raw\/2022_SML.csv\". ","uri":"https:\/\/www.oecd.org\/en\/data\/datasets\/inter-country-input-output-tables.html","citation":"OECD. 2025. \"Inter-Country Input-Output tables (ICIO)\". OECD TiVA database. [dataset]. https:\/\/www.oecd.org\/en\/data\/datasets\/inter-country-input-output-tables.html. Accessed March 2026.","access_type":"Data is publicly available and included in the reproducibility package.","license_uri":"https:\/\/www.oecd.org\/en\/about\/terms-conditions.html","license":"Creative Commons Attribution BY 4.0 licence (CC BY 4.0)"},{"name":"Processing Raw Tariffs into Comparable Tariff Indicators: A Methodological Note","note":"The dataset covers 199 countries and includes MFN and applied tariffs (ad valorem and specific) at the HS 6-digit level, sourced from UNCTAD TRAINS (via WITS). The original raw data exceeds 200 GB and is accessible only to World Bank staff via Cristina Constantinescu. This reproducibility package includes the processed intermediate data and the Stata scripts used to create it (R1_Nomenclature.do and R2_Aggregations.do). File location: data_raw\/tariff_tiva25_2022.dta, which is the starting point of this reproducibility package.","citation":"World Bank. Constantinescu, C. 2025. \"Processing Raw Tariffs into Comparable Tariff Indicators: A Methodological Note\" Mimeo: World Bank [dataset]. Accessed November 2025.","access_type":"Data access was granted directly to the study authors by the data owners. It was obtained with a custom data license that does not allow for redistribution, and it is not included in the reproducibility package; however, intermediate data is included to allow full reproduction of the results.","license":"Custom License"}],"reproduction_instructions":"Run the following scripts in the exact order given, and the results will appear in the \"figure_tables\" folder. Please change the working directory as needed.\n\n1. Change the working directory to `data_processing`, then run `data_extract1.jl`.\n2. Keep the working directory as `data_processing` and run `data_extract2.py` in Python \u2192 Expects the input file `data_raw\/tariff_tiva25_2022.dta` from Constantinescu 2025. This file is already included in the replication package.\n3. Keep the working directory as `data_processing` and run `data_extract3.m` .\n4. Keep the working directory as `data_processing` and run `data_extract4.m`.\n5. Change the working directory to `model_code` then run `AO_Extended.x` in Python, Julia, Matlab, or R (whichever you prefer, where x is the extension for the chosen language. You only need to run one of them; they will give identical results, subject to some minor precision loss. If you decide to use R, remember to change the line with the working directory to the current path. Note: replicators ran the code using the Julia option for step 5. \n6. Change the working directory to `figures_tables`, then run `Exhibits.py` in Python, and outputs will appear in the same folder.\n","technology_environment":"Paper exhibits were reproduced on a computer with the following specifications:\n\u2022 OS: Microsoft Windows 11 Enterprise\n\u2022 Processor: INTEL(R) XEON(R) PLATINUM 8562Y+, 2800 Mhz, 16 Core(s), 16 Logical Processor(s)\n\u2022 Memory available: 128 GB\n"},"datacite":{"creators":[{"givenName":"Erhan","familyName":"Artuc","nameType":"Personal","affiliation":[{"name":"World Bank"}]},{"givenName":"Johan","familyName":"Ortega","nameType":"Personal","affiliation":[{"name":"World Bank"}]}],"titles":[{"lang":"en","title":"Reproducibility package for International Trade Policy And Quantitative Models:\nA Practitioner\u2019s Guide"},{"title":"RR_WLD_2026_593","titleType":"Other"}],"publisher":"World Bank","publicationYear":"2026","types":{"resourceType":"Reproducibility package","resourceTypeGeneral":"Other"},"url":"https:\/\/reproducibility.worldbank.org\/index.php\/catalog\/study\/RR_WLD_2026_593","language":"en"},"tags":[{"tag":"DOI"},{"tag":"Open Code"},{"tag":"Restricted Data"}],"schematype":"script"}