This workbook provides data and data dictionaries for the SFMTA 2014 Travel Decision Survey.
The 2014 Key Findings, Summary Report, and Methodology, including the survey instrument, can be found online at https://www.sfmta.com/about-sfmta/reports/travel-decision-survey-2014.
On behalf of San Francisco Municipal Transportation Agency (SFMTA), Corey, Canapary & Galanis (CC&G) undertook a Mode Share Survey within the City and County of San Francisco as well as the eight surrounding Bay Area counties of Alameda, Contra Costa, San Mateo, Marin, Santa Clara, Napa, Sonoma and Solano.
The primary goals of this study were to:
• Assess percent mode share for travel in San Francisco for evaluation of the SFMTA Strategic Objective 2.3: Mode Share target of 50% non-private auto travel by FY2018 with a 95% confidence level and MOE +/- 5% or less.
• Evaluate the above statement based on the following parameters: number of trips to, from, and within San Francisco by Bay Area residents. Trips by visitors to the Bay Area and for commercial purposes are not included.
• Provide additional trip details, including trip purpose for each trip in the mode share question series.
• Collect demographic data on the population of Bay Area residents who travel to, from, and within San Francisco.
• Collect data on travel behavior and opinions that support other SFMTA strategy and project evaluation needs.
The survey was conducted as a telephone study among with approximately 750 Bay Area residents aged 18 and older. Interviewing was conducted in English, Spanish, and Cantonese. Surveying was conducted via random digit dial (RDD) and cell phone sample.
All three survey datasets incorporate respondent weighting based on age and home ___location; utilize the “weight” field when appropriate in your analysis.
The survey period for this survey is as follows:
2014: October – November 2014
A few questions in TDS 2014 were added after the survey began. In the report, responses that did not answer those questions were excluded from the analysis. The questions that were added late are noted in the TDS 2014 methodology survey instrument.
The margin of error is related to sample size (n). For the total sample, the margin of error is 3.5% for a confidence level of 95%. When looking at subsets of the data, such as just the SF population, just the female population, or just the population of people who bicycle, the sample size decreases and the margin of error increases. Below is a guide of the margin of error for different samples sizes. Be cautious in making conclusions based off of small sample sizes.
At the 95% confidence level is:
• n = 767 (Total Sample). Margin of error = +/- 3.5%
• n = 384. Margin of error = +/- 4.95%
• n = 100. Margin of error = +/- 9.80%