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METHODOLOGY:
Survey of Subway Car Announcements
NYPIRG Straphangers Campaign •
August 2002
The survey was conducted by 61 volunteers during the period from February 2, 2002 to June 14, 2002. Volunteers were instructed to complete a survey entry every time they used the subways throughout that period. The survey form was designed to measure how each subway trip conformed to the guidelines laid out for announcements by MTA New York City Transit. Surveyors noted the date and line of each trip, and noted whether the name of the upcoming station and any applicable transfer information was understandably announced with the car doors open. Surveyors made announcement observations at the following places:
a. the first stop of the trip;
In addition, surveyors recorded whether there was a change in service or delay of two minutes or more. When such a change in service or delay occurred, surveyors noted whether an in-car announcement was made, whether any announcement made was audible and ungarbled, and the exact language of the announcement.
Station name and transfer information announcements were grouped and totaled as one category. Both types of announcements together comprise the "basic" in-car announcement, determined only by characteristics of the line and upcoming station. A basic announcement was deemed adequate if the upcoming station name and any applicable transfer information were announced in an audible and ungarbled manner. In our survey, we recorded 300 basic announcement opportunity observations on each of 22 lines. The Times Square, Rockaway and Franklin Avenue shuttles were not included in the survey.
Our findings then reflect exactly 6,600 basic announcement opportunity observations; of these, our surveyors noted that for the entire system, 73% of announcements (plus or minus 2%) were adequate. The by-line confidence interval in each case is plus or minus 6%. All results are significant at the .05 level.
By-line basic announcement levels measured in our 2002 survey are comparable to those reported in our 2001 and previous surveys; the campaign did not survey basic announcements in 2000.
Of the 20 lines we measured in 2001 for basic in-car announcements, nine showed a statistically significant improvement in performance between the survey periods: the 1, 2, 4, 6, A, B,E, F and Q lines. Seven lines‹the 3, 5, C, D, J, N and R‹showed a significant deterioration in announcement performance. Four lines showed no significant change: the 7, G, M and L. In addition, 2 new routes created by New York City Transit‹the V and W‹were included in our 2002 report, although no comparison to previous findings is possible.
In our 2001 report, we noted that 67% of basic announcements were adequate. This improvement in systemwide performance is significant at the .05 level.
Surveyors were also instructed to record whether there was a change in service or a delay between stations of two minutes or more. When such a change occurred, surveyors noted whether an in-car announcement was made, whether any announcement made was audible and ungarbled, and the exact language of the explanation given.
Straphangers Campaign staff members then examined the transcription of each announcement to determine whether the announcement was "useful" or "not useful" to riders. The campaign categorizes announcements as not useful if they do not give a specific reason for the delay or disruption or if the announcement contained jargon not readily understandable to most riders.
Delay and service change data was not examined on a line-by-line basis. The number of such changes would be too low to permit statistically significant comparisons among lines.
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