ComputerMediated Communication

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Computer-Mediated Communication

• Reputation (Part I)

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Internet situations by frequency continuity
Continuity
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Trust Networks Under Uncertainty

• Trust Networks
• System view
• Ego-centric view

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What are the Solutions to Uncertainty in CMC
Environments?

• Proxies and inferred trustworthiness
• Institutional backing
• Closed Systems versus Open Systems
• Experiential, often negative-only reputations
  (not explicit)
• 3rd party (explicit) reputation

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Information asymmetry Used cars
Before the sale
After the sale.
Buyer
Seller
Images from khulsey.com
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Oh no, lemons!
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Open versus Closed Systems

• Examples
• Open Source System (kernel vs. GUI)
• Wikipedia (are all topics equal?)
• Others?

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Reputation systems
Explicit Implicit Behavior
Ratings by others
Derived from behavior
Join Date Mar 2004 Posts 22
Direct experience
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Explicit reputation systems
/
Useful when Closed system Identity
persistent Coalitions, no alternatives
Useful when Open system Identity transient
Exclusion impossible
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Findings from Yamagishi et al. 2007
Reputation System (Independent Variable) -Positiv
e -Negative -Mixed
Outcome (Dependent Variable) -Price? -Quality
level? -Probability of item being sold? -Time
to sale?
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Quality levels over time
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Levels of dishonesty
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Profit vs. Honesty