There have been studies. In the public transit realm, there was a comparison of the Vancouver Canada Line that was built for the Olympics (an elevated train/su

There have been studies. In the public transit realm, there was a comparison of the Vancouver Canada Line that was built for the Olympics (an elevated train/subway to the airport) and the Eglinton Crosstown in Toronto (mixed underground surface light rail). The TL;DR is that the Vancouver line was mostly on time, on budget, and is working well, while the Eglinton line is massively over-budget, still not ready (should have opened in 2020) with an "indeterminate opening date". The big difference between the two? Vancouver's doled out ONE contract to design, build, and operate the line. It was up to the one company to decide how and where to contract out or subdivide, only being held to certain conditions with reasonable flexibility for unexpected issues. Toronto had a (notoriously bureaucratic provincial government organization called Metrolinx) subdivide a bunch of contracts and essentially act as a project manager (of which a lot was also contracted out) with government-level accountability. The results were all over the place. Tracks were installed with slightly bad gauges, signalling software was bought and didn't have interoperability with other components, substandard construction was used, some contractors were probably hired for political reasons, etc. There's plenty of studies from all over the world that compare cost differences for infrastructure between countries. The French are actually really good at it - they tend to spend a fraction the cost of infrastructure compared to England. https://www.bcg.com/united-kingdom/centre-for-growth/insights/reshaping-british-infrastructure-global-lessons-to-improve-project-delivery https://www.bcg.com/united-kingdom/centre-for-growth/insight...