encyclopedia

MEAN DISTANCE BETWEEN SERVICE INTERRUPTIONS (MDBSI)

The average number of miles a transit vehicle is operated between service interruptions caused by chargeable defects and resulting in a delay and/or inconvenience to customers.

MEAN DOWN TIME (MDT)

The arithmetic mean of the time that the device remains in an inoperable state after it has failed. (NTSC)

MEAN LIFE

The arithmetic mean of time to wear out of all items in the test sample or population. (NTSC)

MEAN MAINTENANCE TIME

The arithmetic mean of the time required to perform a maintenance action. (NTSC)

MEASURE R

A sales tax initiative approved by Los Angeles County voters in 2008. Measure R established a one-half cent sales tax to be used for public transportation purposes, ending in 2039.