Yellow taxis have fewer accidents than blue ones, says study

Researchers from NUS and the Chinese University of Hong Kong say that yellow taxis are more noticeable than blue taxis in both daylight and under street lighting.
Researchers from NUS and the Chinese University of Hong Kong say that yellow taxis are more noticeable than blue taxis in both daylight and under street lighting.PHOTO: BLOOMBERG NEWS

The next time you hail a taxi, take note of its colour, for it might mean a safer ride.

Researchers at the National University of Singapore (NUS) found that taxis painted yellow, a colour that stands out, were involved in significantly fewer traffic accidents than taxis painted blue.

Their results were based on analysing three years' worth of detailed taxi, driver and accident data from a large fleet of over 4,000 yellow taxis and 12,500 blue taxis locally. 

Yellow taxis were found to have about 6.1 fewer accidents per 1,000 taxis every month than their blue counterparts.

It meant an individual was about 9 per cent less likely to be in an accident in one of those.

  • 9% How much less likely an individual in a yellow taxi will experience an accident when compared with someone in a blue taxi.

Professor Ho Teck Hua, NUS deputy president of research and technology and lead investigator of the study, told The Straits Times that the study accounted for a majority - 60 per cent - of taxis in Singapore.

It was conducted in collaboration with Associate Professor Chong Juin Kuan from the NUS Business School and Assistant Professor Xia Xiaoyu from the Chinese University of Hong Kong Business School.

Their findings were published in the scientific journal Proceedings Of The National Academy Of Sciences on Monday.

On the results, Prof Ho said that yellow taxis were more noticeable than blue taxis in both daylight and under street lighting.

"The difference in the accident rate between yellow and blue was highest in street lighting because the difference in visibility of the two colours was most pronounced against the dark background of night."

The study also highlighted the potential economic savings of repainting all the blue taxis in the study yellow. It would cause 917 fewer accidents per year, generating over two million dollars worth of savings.

Studies into the link between vehicle colour and accident rates were previously conducted in 2007 by Monash University in Australia, which found that cars painted in lower-visibility colours such as black, blue and grey, tended to be involved in more accidents.

Singapore's biggest taxi operator, with a fleet of blue cabs, ComfortDelGro told ST that the results of the study were "very interesting" and that the company would take a closer look at them.

Correction note: In our earlier story, we said the results were based on 1½ years' worth of data. It should be three years' worth of data. We are sorry for the error.

A version of this article appeared in the print edition of The Straits Times on March 08, 2017, with the headline 'Yellow taxis have fewer accidents than blue ones, says study'. Print Edition | Subscribe