To calculate fares, app-based ride services such as Lyft and Uber don’t use traditional taxi meters, but instead combine data from GPS and cellular networks to determine a vehicle’s position and movement. To foster trust in the accuracy of fares to customers, drivers, and regulators alike, NIST led a group to develop a standard for evaluating how trip time and distance — key elements of ride fares — are calculated.
Since 2011, the NIST-led U.S. National Working Group on Taximeters has been focused on revising the standards for how fares for transportation services are calculated. New, app-based ride services, which provide millions of rides each day, use proprietary Transportation Network Measurement Systems (TNMS) that analyze a variety of data sources to determine actual time and distance traveled. Until very recently, there were no appropriate, uniform standards for evaluating how companies used TNMS.
Now there is a tentative code, developed by a committee organized by NIST’s Office of Weights and Measures, with expertise from representatives of ride share companies, taxi companies, state and local regulators and others. In August 2017, the California Division of Measurement Standards (CDMS) issued Certificates of Approval to Lyft and Uber for using their respective TNMS to calculate fares, based on this tentative code.
To determine compliance with the code for accuracy and repeatability, CDMS conducted a series of on-road tests (including tests on a certified measured road course) comparing the TNMS-indicated distance travelled and time elapsed with NIST-traceable distance and time standards. CDMS also analyzed rider receipts and driver summaries to ensure compliance with code requirements.
Read more in our news story about this research.
26 organizations participating in development of revised TNMS code
"Through its leadership in the U.S. National Work Group on Taximeters, and recognition that transportation network companies require a separate and unique set of measurement standards, NIST played a critical role in aligning stakeholders across industry and government to develop and promote the Transportation Network Measurement Systems Tentative Code."