Resources, notes, and helpful links used by the Data Department. Organized by section and ordered by importance.
- ❗ denotes required reading for interns and new hires. However, feel free to skip the reading if you're already very familiar with the topic
- ⭐ denotes a recommended resource
Important
See the member org README for a list of useful internal links and bookmarks.
- ❗ CCAO GitHub - Main source for all Data Department code
- CCAO GitLab - Archived. Previous source of all CCAO code
- Cook County Assessor's PIN Search - Our office's application to find information about a PIN
- Cook County Property Info - The County's application to find information about a PIN
- Cook County Data Portal - Public data portal for Cook County
- Cook Viewer - A GIS application for finding PINs
- Subscribe to the CCAO’s external newsletter
- Subscribe to the CCAO’s social media channels:
- IAAO Technical Standards - Technical standards and measurements for the assessment field
Useful materials that give an overview of Cook County's property tax system and provide context about our office, its history, and its problems:
- ❗ Cook County Property Taxes 101 - Brief intro to property taxes, created by the Clerk's office
- ❗ The Tax Divide - Chicago Tribune - An excellent outline of the historical problems with the CCAO
- ⭐ The Cook County Property Tax Extension Process: A Primer - Incredibly useful guide to the intricacies of the entire Cook County tax system
- ⭐ How Lower-Income Americans Get Cheated on Property Taxes - NYTimes - Concise and accessible overview of the nation-wide issue of inequitable assessments
- ⭐ Why Are Property Taxes in Chicago so High? - Chi Hack Night presentation by @dfsnow that introduces the Cook County property tax system and describes some of the root causes of high bills
- How the Illinois Property Tax System Works - The Cook County Treasurer's property tax primer, explains the extension process and some additional things like the scavenger sale and tax liens
- Chicago Inside Out (2018) - Places Journal - Deep dive into the roles and recent histories of the offices that comprise Cook County government, with a particular focus on the impact of property taxes on county services
- Chicago Triad Assessment Report (2018) - Civic Consulting Alliance - Study of 2018 assessment quality in the Chicago triad
- Learn About Illinois' Property Tax System - Illinois Realtors’ video about property tax system and bills
- Why Are My Property Taxes so High? - Neat interactive from Crain's that compares two very different homes that pay roughly the same amount of property tax
- Report on Property Taxes in Wicker Park - Block Club Chicago - Story on how increases in assessed value are affecting Wicker Park
- How Our Property Tax System Robs The Poor to Pay For The Wealthy (2023) - Strong Towns - Documentary about the assessment gap e.g. disparities between low-value and high-value home assessments
- State of Illinois Property Tax System - A long PDF from the Illinois Department of Revenue explaining property taxes in Illinois
- Chicago's Pension Challenge: Understanding Why the Pension Funds are Underfunded - Chi Hack Night - Excellent overview of the problems with Chicago's pension funds
- ❗ R for Data Science - Classic book on data munging and the basics of modeling, highly recommended
- ⭐ Advanced R - Extremely good overview of the R language, its quirks, and how to use it effectively
- ⭐ Package Development in R - Book on how to develop, use, and test R packages
- ⭐ Efficient R Programming - Online book covering how make R code faster to type and run
- Debugging with RStudio - How to use RStudio's built-in debugging features
- Sharing Data - A nice guide on how to share data with others
- Stat 545 - A very thorough walkthrough of data wrangling and exploration in R, does not cover stats
- Tidy Data - Paper describing the structure and utility of 'tidy' data
- ⭐ Colorbrewer 2 - Interactive color picker for cartography
- RStudio Official Cheatsheets - The official cheatsheets maintained by RStudio. These are 1-2 page printouts covering the vital functions of individual libraries
- R Color Palette Cheatsheet - Useful printout covering the colors available in base R
- ❗ renv Overview - A short vignette on how to use
renv, R's local dependency management system - Unit Testing in R - Brief overview of unit testing in R using the
testthatlibrary - Programming with dplyr - A quick rundown on how to write functions using the
dplyrlibrary - Using LightGBM in R - How to use the LightGBM boosted tree framework in R
- Parallel Parameter Tuning in Tidymodels
- ⭐ Shiny Best Practices - An outline of best practices + an entire book of Shiny resources
- Advanced Shiny - A collection of various Shiny tricks for common tasks
- Docker + ShinyProxy Setup - A nice overview of using ShinyProxy with Docker and Docker Compose
- Shiny Modules - An overview of how to use Shiny Modules to better organize your code
- ShinyProxy Config - Website for ShinyProxy, the launcher we used to manage the Data Science Application Server
- ❗ The Missing Semester of Your CS Education - Start here if you're unfamiliar with the command line interface, build tooling, scripting, etc.
- ❗ commit.style - Super brief guide on how to style a commit message. Follow these guidelines
- ❗ Git - The Simple Guide - A simple guide on what git does and how to use it (via the command line)
- ❗ pre-commit introduction - How to install and use pre-commit, our local automatic code review system
- ⭐ How to Write a Git Commit Message - A longer explanation on how to write git commit messages
- ⭐ Docker Overview - Read this to get started with Docker
- ⭐ Dockerfile Best Practices - Required reading if you need to write a Dockerfile
- ⭐ Open Containers Labels Spec - Standardized schema for container labels. Always use when creating new images
- Docker Security Best Practices - Tips for creating secure containers/images
- Reducing Docker Image Size - Blog post on how to reduce the size of images
- Deploying R Models in Production - Walkthrough of how to productionize an R model using Docker. Somewhat outdated now
- Containerizing Data Workflows - Using Airflow with Docker to create DAGs
- ⭐ The Twelve-Factor App - Framework/tips for building a stable application in the modern era
- ⭐ Production Readiness Checklist - Checklist for productionizing an application on AWS
- ⭐ SemVer (Semantic Versioning) - Standard for how to version applications, images, or any software
- Creating Models as Microservices - How to functionalize models as APIs
- Site Reliability Engineering Resources - Huge curated list of useful DevOps/SRE resources
- DevOps Roadmap - Guide for skills needed for DevOps roles
- ⭐ A Deep Dive Into How R Fits a Linear Model - Excellent blog post on how R's
lm()function works under the hood - Linear Regressions in R - Basic overview of creating and visualizing linear regressions in R
- Gradient Descent Overview - Nice visual overview of how different gradient descent algorithms work
- Ridge Regression Overview - Mathy overview of regularization of overfit models
- ⭐ Gradient-Boosted Decision Trees, Explained - An incredible visual explanation of how boosted trees work
- xgboost's Introduction to Boosted Trees - Great overview of the math involved in tree-based models
- LightGBM vs. Catboost Feature Engineering - Nice insight from Kaggle on housing-specific feature engineering
- ⭐ Max Kuhn's Applied Predictive Modeling - One of the best books on predictive modeling. Extremely clear and comprehensive
- Stacked Model Example with Ames Housing Dataset
- Scikit-learn Algorithm Cheatsheet - A flowchart to choosing an ML estimator
- ⭐ 3Blue1Brown - The best YouTube channel about math, statistics, and machine learning that has ever existed
- ⭐ Statistics Done Wrong - Guide to statistics errors, gotchas, and slip-ups
- ⭐ Elements of Statistical Learning - Fairly technical book about stats and prediction. A classic
- Introduction to Statistical Learning - Excellent book on basic stats and techniques. Less technical than Elements
- Statistical Rethinking - Well-known treatment of Bayesian statistics in R
- ❗ Select Star SQL - Excellent interactive book for learning SQL
- ⭐ Use The Index Luke - Explanation of SQL indexing for developers, highly recommended
- Common Table Expression (CTE) Overview - Short guide to using SQL's WITH statement to unnest complicated queries
- SQL Server Tutorials - Advanced tutorials specifically for SQL Server
- ❗ R-Spatial Spatial Data Science Book - Extremely thorough, brand-new book on spatial data in R. Also covers general GIS concepts like reference systems, geometry types, etc.
- ⭐ CSDS Spatial Data Tutorials - List of tutorials for manipulating spatial data in R, created by UChicago's Center for Spatial Data Science
- Simple Features for R - Long vignette on R's
sflibrary, its design, and how to use it - Geofabrik - Data extracts from the entire OpenStreetMap (OSM) database. Useful for calculating distances
- Osmium Tool - Tool for manipulating and filtering OSM data. Requires using a command line
- Geocomputation in R - Free book covering lots of geospatial munging in R