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METHODOLOGY: NYPIRG Straphangers Campaign Survey of Subway Car Announcements August 2001
Our August 2001 announcement survey is a follow-up to the four past surveys on announcements released by the Straphangers Campaign between 1997 and 2000.
The survey was conducted by 51 volunteers during the period from February 26, 2001 to June 1, 2001. 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:
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 20 lines. The Times Square, Rockaway and Franklin Avenue shuttles were not included in the survey.
Our findings then reflect exactly 6,000 basic announcement opportunity observations; of these, our surveyors noted that for the entire system, 69% 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 2001 survey are comparable to those reported in our 1999 and previous surveys; the campaign did not survey basic announcements in 2000.
Of the 18 lines we measured in 1999 for basic in-car announcements, 17 showed a statistically significant improvement in performance between the survey periods, all but the R line. Two lines were not included in our 1999 survey‹the J/Z and M lines‹because of an insufficient number of observations. No comparison can thus be made to the 2001 findings for these lines.
In our 1999 report, we noted that 47% 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.
Our surveyors rated 127 delays and service changes during the survey period, of which 26 were followed by an ungarbled, audible and useful explanation for the disruption in service (20%, plus or minus 8%). These findings are consistent with those published in our 1999 report, in which we recorded 27% ungarbled, audible and useful announcements in response to 135 measured delays and service changes. The difference in results between the two survey periods is not statistically significant at the .05 level.
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.
In July 2001, the campaign released our annual state of the subways report. It showed a decline in adequate announcements as opposed to the improvement shown in this survey. The difference between can be attributed to the time periods covered: The state of subways report used New York City Transit data and compared the first half of 2000 to the second half of 1999. Our 2001 announcement survey compares the period February-June of 2001 with December 1998-July 1999.
According to New York City Transit data, basic announcements improved between the first three months of 1999 and 2001, going from 52% adequate to 79% adequate, while they declined between the second half of 1999 and the first half of 2000, from 60% to 48%.
summary of findings | news release | methodology | table 1 | table 2
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