What are the chances that NJ Transit will cause you to miss the Dinky?

This article is part of an ongoing collaboration between Pranav Badami and me analyzing real-time NJ Transit data that we scraped. You can find the previous article here.

With spring break descending on Princeton University’s campus this week, many students are taking this opportunity to escape the Orange Bubble for a bit. Whether you’re going home, flying around the world, or just making a short trip to New York City or Philadelphia, chances are taking NJ Transit will be a part of your journey.

Every day, the “Dinky,” or the Princeton Shuttle, as it’s officially referred to as by NJ Transit, transports countless passengers back and forth between the Princeton and Princeton Junction train stations, serving as a crucial link between the Princeton campus and the rest of the NJ Transit system for commuters, tourists, and students alike. Plus, with a consistent travel time of 5 minutes, the Dinky generally beats traffic if you manage to catch it on time.

Surviving multiple station changes in its recent history, the Dinky is truly Princeton’s “Ol’ Reliable.” In fact, it’s so reliable that we actually decided to exclude it in our systemwide analysis because it was biasing our results. According to NJ Transit’s real-time data feed, 99%¹ of Dinky trains leave within the minute that they are scheduled to, regardless of the direction they are traveling in.