City Services Satisfaction Survey 2012 City Services Satisfaction Survey - Page 79

Data Collection Internet All interviewing was completed over the Internet via Decision Analyst’s secure web server. All data on the Internet server, and all communication between Decision Analyst’s internal computers and the Internet server, are using secure sockets layer (SSL) certificates. Incoming survey data are stored in a redundant disk array system. Multiple sample sources (provided by the City for email lists and postcard mailing lists) were utilized to invite a representative sample of Arlington citizens (mirroring the age, gender, and district distribution of Arlington households). Respondents were screened to identify Arlington citizens and those who qualified were invited to complete the survey. As extra security, participants had to enter their email addresses or personal passwords before they could enter the survey. As the survey progressed, the data were transferred from the Internet server to Decision Analyst’s internal computers, safe behind a protective “firewall.” Data Tabulation The final statistical tables were created via UNCLE . This comprehensive data management and cross-tabulation system has one overriding objective in mind: the production of consistently accurate statistical tables. For example, most formatting is automatic within UNCLE to eliminate format-related errors. The software contains hundreds of embedded error-trapping algorithms to eliminate syntactical errors. The system produces a Summary Report, to condense all of the programmer's instructions into a simple, easy-to-read format, which makes any programming errors easy to find during quality-control checking. Another quality-control procedure involves a thorough crosscheck of percentages in the statistical tables against the same percentages in an UNCLE Marginal report. (Within UNCLE , the Marginal program and the program module which compiles the statistical tables are based upon different algorithms so that each can serve as an independent accuracy check upon the other.) Additionally, tabulation programmers follow a multi-step, quality-control checklist to ensure produc- tion of accurate statistical tables. All questionnaires and source documents will be stored by Decision Analyst for six months before being destroyed. The data itself will be stored on magnetic tape for three years. During this time period, additional cross-tabulations or statistical analyses can be purchased at Decision Analyst's standard hourly rates. Decision Analyst, Inc. 79