Modelling

Open Source Property Assessment: Tidymodels to Allocate $16B in Property Taxes - posit::conf(2023)

Presented by Nicole Jardine and Dan Snow

How the Cook County Assessor’s Office uses R and tidymodels for its residential property valuation models.

The Cook County Assessor’s Office (CCAO) determines the current market value of properties for the purpose of property taxation. Since 2020, the CCAO has used R, tidymodels, and LightGBM to build predictive models that value Cook County’s 1.5 million residential properties, which are collectively worth over $400B. These predictive models are open-source, easily replicable, and have significantly improved valuation accuracy and equity over time.

Join CCAO Chief Data Officer Nicole Jardine and Director of Data Science Dan Snow as they walk through the CCAO’s modeling process, shares lessons learned, and offer a sneak peek at changes planned for the 2024 reassessment of Chicago.

Conformal Inference with Tidymodels - posit::conf(2023)

Presented by Max Kuhn

Conformal inference theory enables any model to produce probabilistic predictions, such as prediction intervals. We’ll demonstrate how these analytical methods can be used with tidymodels. Simulations will show that the results have good coverage (i.e., a 90% interval should include the real point 90% of the time).