Cognitive Social Structure

Coping with inaccurate perception of social networks

Self-reporting is inaccurate

• Bernard, Killworth & Sailer, 1979• Collect data from teletype owners

• “Who have you communicated with last month”• “Who might you communicate in the next

month?”• First study: 25 respondents; then 54 informants• Accuracy of reporting: ~52%

• Just slightly higher then chance!

More experiments

• Total of seven experiments, ‘79-84• HAM radio operators• University department• Commercial office• Fraternity• Early email network (> 200 respondents)

Results of experiments

• Informants who regularly keep records are not more accurate

• Slightly intrusive observation does not affect outcome

• No improvement with repeated studies• “who do you like” = “who do you talk to”• Significance questions do not affect outcome• Overall, people can recall < 50% of their

communications

Timing results

• Short-term and long-term results are more accurate then mid-term

• Short-term memory is lost rapidly

• Long-term memory relies on generalization

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Over- and under-reporting

• Telephone study (Hyett):• People who make few calls tend to over-

report• People who make very many calls tend to

under-report• Only 71% report “anywhere in a ballpark”

Conclusion

• “…on the basis of seven experiments, what people say about their communications bears no useful resemblance to their behavior.”

Can data be washed?

• Not really - • Timing study only accounts for 6%

variance• Over- and under- reporting:

• 49% of variance

Turning to advantage

• Inaccuracies of perception tell us something about the processes

• Perceptions might be as important as the “true network”

• Ways to address:• Theory to relate perceptions to reality• Focus on perceptions and study them as

phenomenon

Cognitive dissonance

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• Perception of balance is as good as balance

Cognitive Social Structure

• “Normal network” : adjacency matrix

• Cognitive Social Structure (CSS): perceptual adjacency matrix

Cognitive Social Structure

• N x N x N 3D matrix:• ri,j,k=1 : k perceives communication

between i and j.

I,j,k

Slicing the data

• Hold constant the perceiver dimension:

Can deduce:

• Perception of balance• Perceived structural equivalence

• Look at correlation of slices of different actors• In markets, people copy behaviours of these

perceived to be similar (Allen, 1978)

Dicing the data

• Locally Aggregated Structures• “How do you perceive your own

communications?• Row dominated

• Column dominated

Kneading the data

• LAS Intersection Rule:

• LAS Union Rule:

Use of LAS rules:

• Friendship better determined by intersection rule• Mutual nature of friendship is important

• Communication better reported by union rule• General trend toward under-reporting

Consensus Structure

• Considers everybody’s perceptions of ri,j in determining r’i,j:

• f is an arbitrary function of perceptions, for example:

Use of Consensus Structure

• Freeman (1986):• “…the underlying truth about some statement is

best predicted from a weighted average of each observer’s perception or guess about the truth”

• Computation of weights “…complicated and important”

Accuracy of Network Perception

• Number of ties among alters that ego percieves correctly

• High cognitive accuracy corellated with high network performance