{"type":"script","doc_desc":{"producers":[{"name":"Reproducibility WBG","abbr":"DECDI","affiliation":"World Bank - Development Impact Department","role":"Verification and preparation of metadata"}],"prod_date":"2026-10-23","version":"1"},"project_desc":{"authoring_entity":[{"name":"Geetika Nagpal","affiliation":"World Bank","email":"gnagpal@worldbank.org"},{"name":"Sahil Gandhi","affiliation":"University of Manchester","email":"sahil.gandhi@manchester.ac.uk"},{"name":"Vaidehi Tandel","affiliation":"University of Manchester","email":"vaidehi.tandel@manchester.ac.uk"}],"title_statement":{"title":"Reproducibility package for Economics Of Vertical Growth Of Slums: Floors, Rents And Vertical Sorting In Mumbai","idno":"RR_IND_2026_780"},"data_statement":"The reproducibility package relies on 3 types of data: open, limited-access, and restricted data (available only from the data owners). For the source, access type, file location, and citation of each dataset, refer to the Datasets section and the README file.","software":[{"name":"R","version":"4.5.3"},{"name":"Stata","version":"19.5 MP"}],"scripts":[{"title":"Reproducibility package for Economics Of Vertical Growth Of Slums: Floors, Rents And Vertical Sorting In Mumbai","date":"2026-10","notes":"Computational reproducibility verified by Development Impact (DECDI) Analytics team, World Bank.","instructions":"See README in reproducibility package.","file_name":"RR_IND_2026_780","zip_package":"RR_IND_2026_780.zip","dependencies":"R dependencies are listed in the file renv.lock. Stata dependencies are listed in the ado folder."}],"repository_uri":[{"name":"Reproducible Research Repository (World Bank)","uri":"https:\/\/reproducibility.worldbank.org"}],"production_date":"2026-10-23","abstract":"In response to rising population densities in land-scarce developing country cities, slum settlements are increasingly growing vertically. This paper is, to our knowledge, the first to study the determinants of slum building heights and estimate its relationship with rents. Using satellite-derived building heights for Mumbai's slums, we first show that informal building heights display a bid-rent gradient as height falls with distance from the city's main business districts and rises with residential land values. We then ask how height is priced within a building. We conduct a survey of tenant households across slum buildings experiencing high vertical growth and show that rents fall by 3.2--3.4% for every additional floor. We test for mechanisms that explain this penalty and find a statistically significant impact of recorded temperature, roof leakage perception, and roof material. We also find patterns of vertical sorting where poorer households are more likely to occupy upper floors, with each additional floor associated with a 0.21 lower household asset index.","geographic_units":[{"name":"India","code":"IND"}],"keywords":[{"name":"Informal Housing"},{"name":"Vertical Densification"},{"name":"Household Sorting"},{"name":"Slum Settlements"},{"name":"India"}],"output":[{"type":"Working Paper","description":"Policy Research Working Paper (PRWP)","title":"Economics Of Vertical Growth Of Slums: Floors, Rents And Vertical Sorting In Mumbai"}],"language":[{"name":"English","code":"EN"}],"technology_requirements":"Run time: ~ 20 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":"MIT License","uri":"https:\/\/opensource.org\/license\/mit"},{"name":"World Bank IGO Rider","uri":"https:\/\/github.com\/worldbank\/metadata-editor\/blob\/main\/WB-IGO-RIDER.md"}],"contacts":[{"name":"Geetika Nagpal","affiliation":"World Bank","email":"gnagpal@worldbank.org"},{"name":"Reproducibility WBG","affiliation":"World Bank","email":"reproducibility@worldbank.org"}],"datasets":[{"name":"Slum Settlement Boundaries, Mumbai","note":"File location: data\/raw\/slum_map\/slums_mumbai.shp (and .shx, .dbf, .prj, .qpj). 7,453 polygons. Shared with the authors by the Municipal Corporation of Greater Mumbai (MCGM) under a data sharing agreement. Not public; cannot be redistributed or made public. Used by code\/00_construct_grid_dataset.R, code\/appendix_table_1.R and code\/figure2_mean_slum_height_2023.R. Accessed January 2019.","access_type":"Data access was granted directly to the study authors by the data owners\/managers. It was obtained with a custom data license that does not allow for redistribution and it is not included in the reproducibility package.","license":"Custom License (data sharing agreement with MCGM; not redistributable)","citation":"Municipal Corporation of Greater Mumbai. 2019. \"Slum Settlement Boundaries, Mumbai\" [dataset]. Shapefile shared with the authors. Accessed January 2019."},{"name":"Mumbai Wards Map","note":"File location: data\/raw\/wards\/wards.shp (and companion files). 24 wards. Boundaries from MCGM, republished by OpenCity. Included in the package under the Public Domain designation listed by OpenCity (certified open under the Open Definition); see LICENSE.txt. Accessed May 2025.","access_type":"Data is publicly available and included in the reproducibility package.","license":"Other (Public Domain), as listed by OpenCity","uri":"https:\/\/data.opencity.in\/dataset\/mumbai-wards-map","citation":"Municipal Corporation of Greater Mumbai. 2025. \"Mumbai Wards Map\" [dataset]. Published by OpenCity. https:\/\/data.opencity.in\/dataset\/mumbai-wards-map. Accessed May 2025."},{"name":"Mumbai Slum Building Height Rasters, 2016 and 2023","note":"File locations: data\/raw\/240516_BOM_BldHgt_2016_3m_GK_V2.tif and data\/raw\/240516_BOM_BldHgt_2023_3m_GK_V2.tif. Building heights in metres, 3 m resolution, UTM zone 43N, covering Mumbai. Produced for the authors by a firm they hired (MapSolve AI, info@mapsolve.ai) from SPOT 6\/7 stereo satellite imagery (Airbus Defence and Space) purchased from Apollo Mapping, with heights derived following Tripathy et al. (2022). The imagery was purchased under an academic license that does not allow the authors to share the imagery or the derived rasters. To obtain the same inputs, purchase 1.5-Meter SPOT Stereo imagery over Mumbai from Apollo Mapping (https:\/\/apollomapping.com\/spot-satellite-imagery): archive imagery for 2016 (acquired 14 April 2016) and a new tasking for 2023 (acquired 23 October 2023), then apply the height-retrieval method in Tripathy, P., Balakrishnan, K., de Franchis, C., and Kumar, A. (2022), Environment and Planning B: Urban Analytics and City Science 49(9): 2312-2330. 2016 raster received 9 November 2022; 2023 raster received 24 October 2023.","access_type":"Data access requires purchase or human approval and is not included in the reproducibility package.","license":"Apollo Mapping academic license (imagery and derived rasters not redistributable)","uri":"https:\/\/apollomapping.com\/spot-satellite-imagery","citation":"Authors' compilation. 2023. \"Mumbai Slum Building Height Rasters, 2016 and 2023\" [dataset]. Based on SPOT 6\/7 stereo imagery (Airbus Defence and Space) purchased from Apollo Mapping and processed by MapSolve AI, following Tripathy et al. (2022)."},{"name":"Mumbai Ready Reckoner Zones and Residential Rates, 2023-24","note":"File location: data\/raw\/RR\/ready_reckoner_2023.shp (and companion files). 968 zones; the code uses the fields ZONE and RESIDENTIL (residential rate). Authors' compilation of two sources. (1) Zone polygons: MCGM, shared with the authors under a data sharing agreement; not public and not redistributable; accessed July 2016. (2) Residential rates: Government of Maharashtra, Annual Statement of Rates (Ready Reckoner) 2023-24, public, accessed 2025 from a private website that republishes the rates: https:\/\/www.e-stampdutyreadyreckoner.com\/reckoner\/2023\/mumbai\/mumbai-city and https:\/\/www.e-stampdutyreadyreckoner.com\/reckoner\/2023\/mumbai\/mumbai-suburban.","access_type":"Data access was granted directly to the study authors by the data owners\/managers. It was obtained with a custom data license that does not allow for redistribution and it is not included in the reproducibility package.","license":"Custom License (zone polygons: data sharing agreement with MCGM; rates: public)","citation":"Authors' compilation. 2025. \"Mumbai Ready Reckoner Zones and Residential Rates, 2023-24\" [dataset]. Based on Municipal Corporation of Greater Mumbai zone polygons and the Government of Maharashtra Annual Statement of Rates 2023-24, Mumbai City and Mumbai Suburban."},{"name":"Mumbai Slum Tenant Household Survey","note":"File location: data\/raw\/Slum_Mumbai_Aug2026.dta. Primary data collected by the authors: 227 tenant households in 113 buildings in Bandra East, Chembur and Malad West; interviews from 16 May to 1 June 2025. The file contains respondent and enumerator names, phone numbers and building GPS coordinates, and cannot be redistributed under the ethics requirements of the University of Manchester (ethics committee reference 2024-21428-37856). Not included in the package. A de-identified version (only the variables used by code\/02_survey_tables_figures.do, with building identifiers recoded and coordinates removed or coarsened) will be deposited in a data repository, such as Harvard Dataverse, after the paper is published. Until then, contact Vaidehi Tandel (vaidehi.tandel@manchester.ac.uk). Access date not applicable (primary data).","access_type":"Data is forthcoming to a public data repository upon paper publication in the journal. ","license":"University of Manchester ethics requirements (not redistributable)","citation":"Gandhi, Sahil, Geetika Nagpal, and Vaidehi Tandel. 2025. \"Mumbai Slum Tenant Household Survey\" [dataset]. Collected May 2025. To be deposited after publication."}],"reproduction_instructions":"To reproduce the findings in this paper, a replicator must:\n1. **Secure Access to Data:** Access the datasets not included in the package. See the Datasets section for more details.\n2. **Run the Package:**\n     - Open the R project `vertical_slums_replication.Rproj`, restore the environment by running renv::restore() and following the prompts.\n     - Open the `main.R` and run the code.\n     - Update the working directory in line 15 of the do-file `00_master.do`, and run it\n\nSince not all the data is included, the package includes the results produced by replicators. These files can be used to review the results presented in the paper.","technology_environment":"Paper exhibits were reproduced on a computer with the following specifications:\n\u2022 OS: Windows 11 Enterprise\n\u2022 Processor: INTEL(R) XEON(R) PLATINUM 8562Y+ 2.80 GHz (2 processors)\n\u2022 Memory available: 32.0 GB"},"datacite":{"creators":[{"givenName":"Geetika","familyName":"Nagpal","nameType":"Personal","affiliation":[{"name":"World Bank","affiliationIdentifier":"https:\/\/ror.org\/00ae7jd04","affiliationIdentifierScheme":"ROR","schemeUri":"https:\/\/ror.org"}]},{"givenName":"Sahil","familyName":"Gandhi","nameType":"Personal","affiliation":[{"name":"University of Manchester","affiliationIdentifier":"https:\/\/ror.org\/027m9bs27","affiliationIdentifierScheme":"ROR","schemeUri":"https:\/\/ror.org"}]},{"givenName":"Vaidehi","familyName":"Tandel","nameType":"Personal","affiliation":[{"name":"University of Manchester","affiliationIdentifier":"https:\/\/ror.org\/027m9bs27","affiliationIdentifierScheme":"ROR","schemeUri":"https:\/\/ror.org"}]}],"titles":[{"lang":"en","title":"Reproducibility package for Economics Of Vertical Growth Of Slums: Floors, Rents And Vertical Sorting In Mumbai"},{"title":"RR_IND_2026_780","titleType":"Other"}],"publisher":"World Bank","publicationYear":"2026","types":{"resourceType":"Reproducibility package","resourceTypeGeneral":"Other"},"url":"https:\/\/reproducibility.worldbank.org\/index.php\/catalog\/study\/RR_IND_2026_780","language":"en"},"tags":[{"tag":"DOI"},{"tag":"Open Code"},{"tag":"Restricted Data"}],"schematype":"script"}