We're the Cook County Assessor's Data Department. We make predictive models to help determine the assessed value of every residential and condominium property in Cook County. We also make tools and reports to make the Cook County property system more transparent, predictable, and fair.
Our tiny team has done some big work since 2018. Here are some of the things we're most proud of:
- model-res-avm 🏠 - Model to create assessed values for all single-family/multi-family (up to 6 unit) properties in Cook County
- model-condo-avm 🏢 - Predictive model for all residential condominium properties in Cook County
- ptaxsim 💵 - Database and R package to estimate counterfactual Cook County property tax bills
- data-architecture 🔧 and documentation 📖 - ETL/ELT stuff, SQL definitions, lineage graphs, column descriptions, etc.
- Cook County Open Data 📊 - Public datasets, including historic assessed values, property characteristics, appeals, etc.
- Check out the public repo for data requests 🔍, our talks 💁, and ways to contact us 📫.
- View all our open issues ✅ and pull requests 🚀. We welcome forks, pull requests, and new issues!
- Visit our wiki 📘 to learn more about the Data Department's mission, vision, and practices.