Eurostat

Data collection

Presented by

• Johan Erikson • Statistics Sweden

Data collection - outline

• Modes of data collection• Choosing the mode(s)• Mixing modes• Choosing the contact strategy• Setting up the collection – web questionnaires• Data collection modules in the handbook

Modes of data collection

• Interviewer-administered modes– Telephone interviews (CATI)– Face-to-face interviews (CAPI)

• Self-administered modes– Paper questionnaire– Electronic questionnaire (CAWI, downloadable forms,

and different types of file transfer)

Modes of data collection (2)

Modes without respondent– Electronic data interchange (EDI, XBRL)– Observation– Administrative data (secondary data)

Choosing the mode

• Factors to consider:– Response process– Response burden– Desired data quality (response rate, measurement error)– Available resources

Budget Staff IT-resources and respondent´s technical conditions

– Respondent expectations– Topic of the survey– Timetable

Response process

• Assigning priorities• Authorisation• Data in records• Gatekeepers• More than one respondent

• Based on this, self-administered modes are most common in business surveys

Response burden

• Questionnaire design vs data availability• Timing• Finding the right person(s) and dividing tasks• Questionnaire design is vital!

Data quality

• Response rates are generally higher in interviewer-administered modes

• However, interviews might not be an alternative• And business surveys are often mandatory• Helping the respondent to higher quality

– Pre-printing– Built-in functionality in EQ

Mixing modes

• Using more than one mode• Costs of mixing modes:

– Several questionnaires, set-up costs– Risk of mode effects– Staffing

• Advantages of mixing modes– Coverage– Response rates and data quality– Costs in the collection stage

Mixing modes

• Two main types of mixed mode• Parallel approach

– Lets the respondent choose

• Sequential approach– Primary mode offered first– Typically, cheapest mode first

• A third approach: Differentiating modes:

– The most expensive modes not used for all businesses

Most common data collection strategy:

• Use already collected data when possible• Promote the main mode (web) all the way• Design for mixed modes• Use modes in sequence, starting with the

cheapest• Optimise the questionnaire design for each mode• Have special treatment of the largest businesses

Contact strategy

• When to send– Enough time to finish the survey– Data availability– Reasonable time to respond– No. of reminders– Other surveys

• What to send– Based on the mixed mode strategy– Paper form or not?

Contact strategy (2)

• Method of contact– Mail (letter)– E-mail– Telephone

• Who to contact– Reaching the best respondent– Difference between small and large enterprises– Using previous contacts– Using a generic role

Contact strategy (3)

• New businesses in the survey– Specific treatment or not?– Sample rotation, ongoing surveys– Finding the right person– Showing the enterprise the importance of replying

Contact strategy (4)

• Specific treatment:– Single point of contact– Building relations– Profiling statistical units– Finding contact persons– Support for the enterprise– Support for survey staff– Enterprise-specific arrangements– Coherence analysis

Contact strategy (5)

• Feedback to respondents– General feedback– Enterprise-specific feedback

• Responsive design issues– Making design choices based on results so far:

Switching modes Switching contact methods Different questionnaires Penalties/fines

Set-up collection: Web questionnaires

• Introduction letter– Describing the survey– Letting the businesses prepare

• Login procedures– Security issues– Must be easy

Web questionnaires (2)

• Editing during data collection– Hard errors / soft errors– Client-side / Server-side

• Platforms and browsers• Response time• Several response sessions• Web-site / Business portal

Web questionnaires (3)

• More advanced electronic alternatives:– Touch-tone data entry– File transfer– File import (XBRL)– Electronic data interchange

Data collection modules

• Main theme module - overview• Design of data collection 1 – modes• Design of data collection 2 – contact strategy• Techniques and tools• Mixed mode• CATI allocation• Collection and use of secondary data