I've been a little absent lately
stuck in traffic for many hours doing some exploratory fieldwork in Rio de Janeiro. One day, it took me 4,5 hours to travel 29 km by car. This is 3 times as estimated by Google Maps without traffic. Google's estimate for for the same journey using public transport is 2h41m without traffic.
The problem is: 'no traffic' is not a reasonable assumption great urban areas like Rio. Under such congested contexts, GTFS data is hardly accurate and that's when real-time data (e.g. GPS) becomes necessary for more reliable analysis.
Rio has the worst traffic conditions in Brazil
and many other problems, and yet it is impossible not to love this city.