1. (brief descriptions) Documentary research Case studies Action research
Unobtrusive research
(brief descriptions) Documentary research Case studies Action research

2. Unobtrusive research
Studying economic or social behavior without affecting it (can be qualitative and/or quantitative). Examining ´clues´ instead of actual behavior.
Some unobtrusive research types:
Content analysis (e.g. documentary research)
Secondary statistical data analysis
Unobtrusive online research
Comparative and historical research
Meta-analysis of research papers

3. Content/documentary analysis
The study of recorded human communications or products (books, websites, paintings, etc.).
Considerations:
Topics appropriate
Conceptualization
Units of data collection vs. units of analysis
Sampling (units of analysis)
Coding (transforming raw data into standardized form)
Manifest content (surface)
Latent content (underlying meaning)

4. Useful sources (examples only)
Communications ( s, letters, blogs, social media etc.)
Individual (personal) records (diaries, notes, calendars etc.)
Organizational sources (agendas, administrative records, policy statements, reports, book keeping etc.)
Government sources
Media sources (TV, radio, online media, printed media etc.)

5. An example (recording table for TV violance vs. target group research)

6. (source: http://keithsneuroblog.blogspot.hu)
Meta-analysis
(source:

7. Advantages May have fewer resource requirements Unobtrusive
Longitudinal studies may be feasible
Can provide comparative and contextual data
Can result in unforeseen discoveries
Permanence of data

8. Disadvantages
May be collected for a purpose that does not match your need
Access may be difficult or costly
Aggregations and definitions may be unsuitable
No real control over data quality
Initial purpose may affect how data are presented