Gavin Rozzi's Blog & Insights

All Articles

• Apr 27, 2026

  How to plot ZIP codes on a map in R with zipcodeR

  Build choropleth and dot maps of US ZIP codes in R using zipcodeR for the data layer and tigris + sf + ggplot2 for the geometry. Includes interactive maps with leaflet.

• Apr 26, 2026

  How to assign ZIP codes to geographic regions in R

  Roll up ZIP-level data to county, state, MSA, or any custom region in R using zipcodeR. Covers reverse_zipcode() for built-in geographies and crosswalk joins for custom regions.

• Apr 25, 2026

  How to calculate distance between ZIP codes in R

  A practical guide to calculating great-circle distance between ZIP codes in R using zipcodeR — including pairwise lookups, batch calculations, and finding all ZIPs within a radius.

• Feb 15, 2024

  React and TypeScript Best Practices for Government Applications

  Lessons learned building production React applications with TypeScript for government clients who demand reliability, accessibility, and security

• May 12, 2023

  Digital Transformation in Government: Lessons from the Trenches

  Practical insights on modernizing government technology infrastructure and processes from years of hands-on experience

• Apr 17, 2022

  A Spatial Analysis of New Jersey's Medical Cannabis Dispensary Accessibility

  An isochrone-based GIS analysis revealing that over 756,000 New Jerseyans in 110 municipalities face 30+ minute drives to the nearest medical cannabis dispensary.

• Feb 4, 2022

  New Jersey's official geocoding API now has a client for R

  Using New Jersey's official state geocoding service just got easier! This post introduces njgeo, a new R package that simplifies working with New Jersey-specific spatial datasets.

• Jan 2, 2022

  2022 New Jersey Congressional Redistricting Map

  An analysis and visualization of New Jersey's new congressional districts adopted by the Redistricting Commission, created using R and Leaflet.

• Oct 3, 2021

  What Social Media Data Tells Us About the 2021 New Jersey Governor's Race

  A sentiment analysis of tweets about the Murphy-Ciattarelli gubernatorial race reveals key differences in campaign rhetoric, word choice, and online engagement.

• Mar 31, 2021

  Automating web scraping with GitHub Actions and R

  GitHub Actions is a powerful tool for automating workflows. This post presents an example of using GitHub Actions to automatically run a web scraper in R and commit the results to a repository.

• Jan 20, 2021

  njtr1: An R Package to Download & Analyze New Jersey Car Crash Data

  Introducing njtr1, an R package that automates the acquisition and cleaning of motor vehicle crash data published by the New Jersey Department of Transportation.

• Dec 13, 2020

  What's New in zipcodeR v0.2?

  A review of the new features in zipcodeR v0.2, including congressional district lookups, FIPS code searches, and community-contributed improvements.