1. Nature of the unobtrusive measures of behavior.
 

2. Varieties of unobtrusive measures:
 

a. Physical traces

• Use traces
• Products

b. Archival research

• Census data
• Court records
• Genealogical data
• Corporate annual reports
• Patent office records
• credit history
• health history data
• educational records
• personal correspondence
• diaries
• etc.

c. Varieties of archival research
 

• Program evaluation
• Content analysis

d. Pros and cons of archival research

ADVANTAGES:

• the amount of information available
• can converge with the results of laboratory research, thus increasing external validity.
• archival research is non-reactive.

DISADVANTAGES:

• The possibility that data is missing or is not representative
• Experimenter bias – selecting only information that supports the hypothesis