1. Archives and traces

2. Physical traces & Archival Research
no reactivity (no Hawthorne effect, subject bias etc)
can be done with subject anonymity
especially useful for validity check
of measures
external validity
very good for long term changes
life histories (impact of divorce, illness, death)
different epochs ( eg baseball batting averages)
Huge amount of data available

3. Problems –
Not everything is saved – some traces last longer than others, questions may change over years.
Records kept but may not be representative of all data.
Little information stored when nothing happens.
Some records maybe easier to retrieve than others.
Recording errors
3rd variable over time
Spurious relationships found

4. Problems ctd
Experimental bias – more information available than you can use So need to choose.
Need to interpret data that is already there.
Need great operational definitions
Access - government private or corporate?

5. How to objectively code information
1) Identify data source
2) Sample data
3) Code records – classify events and behaviors into clear categories.
Record time, words, space, events devoted to category.
Trained raters for qualitative judgments

6. Running records – eg congressional records , baseball stats continuously updated – used for epoch comparison
Personal records –diaries, blogs – eg used in social network research
News media – not unbiased – eg lost and found columns used for altruism research