1. Computer-Mediated Communication
Reputation (Part II)

2. Distilling reputation from various sources of information
What is the difference between reputation and opinion?
Some implied notions of reputation: predicting future behavior? Public versus private reputation?
Subjectivity Issue: interpretation of the “same facts” still up for interpretation
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

3. Computer-Mediated Communication — Cheshire & Fiore
“Reputation” systems
Explicit
Implicit
Behavior
Ratings by others
Derived from behavior
Join Date: Mar 2004
Posts: 22
What are some problems with implicit “reputation” information? Hard to be sure what it means, whether it tells you anything useful.
Direct experience
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

4. Computer-Mediated Communication — Cheshire & Fiore
Resnick et al. 2006
Effect of strong reputations on revenues compared to those without reputation
Effect of “negatives” in a brief reputation on outcome of revenue
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

5. Matched Pairs by Different Sellers
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

6. Computer-Mediated Communication — Cheshire & Fiore
Reputation Effects
Do strong reputations matter?
What is the impact of negative reputation marks in a mixed reputation system such as eBay?
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

7. Critiquing Methodological Approaches to Similar Problems
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

8. Two approaches to studying online reputation system (Ebay)
Why study it in a lab?
Why study it in a field experiment?
Assignment: maybe random, maybe deliberate, but controlled by the experimenter.
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

9. Computer-Mediated Communication — Cheshire & Fiore
The Validity Problem
Internal Validity
External Validity
Internal Validity: It is clear what is being measured and we try hard to account for other factors of influence
External Validity: Generalizability…is this generalizable to other contexts other than the lab?
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

10. External Validity: Generalizing From Experiments?
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

11. Ecological Validity: Approximation of Real-Life Activity
Ecological Validity is often viewed as a “Threat” to external validity; even a subset of the larger ‘external validity problem’.
Resnick et al.
Yamagishi et al.
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

12. Computer-Mediated Communication — Cheshire & Fiore
Resnick et al. 2006
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

13. Computer-Mediated Communication — Cheshire & Fiore
“Reputation” systems
Explicit
Implicit
Experience
Ratings by others
Derived from behavior
Join Date: Mar 2004
Posts: 22
What are some problems with implicit “reputation” information? Hard to be sure what it means, whether it tells you anything useful.
Direct experience
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

14. Computer-Mediated Communication — Cheshire & Fiore
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

15. How does a “good” poster look?
More active posters are more interactive
Regular, active (but not overactive) participation: good
Posting in too many groups or dominating threads: bad
More posts, more threads <==> greater fraction are replies
Regular, active associated with wanting to read more in the future, respect, trust
Too many groups, dominating threads associated with not wanting to read more in the future. (Spam; being a jerk)
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

16. Computer-Mediated Communication — Cheshire & Fiore
Why do this?
Predicting how real people would have rated if we had explicit ratings on a huge scale.
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

17. Other Implicit ‘Reputation’ Information in CMC?
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

18. Another side of reputation…“
Internet markets also have significant advantages in establishing reputations … any information that is gleaned can be near costlessly tallied on a continuing basis … [and] that information can be near costlessly transmitted to millions of potential customers.
— Resnick et al. 2006, p. 80 ”
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

19. Computer-Mediated Communication — Cheshire & Fiore
The CMC and ‘Offline’ Reputation Link: Emergent Reputation Systems and Identity
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

20. So, Is ‘Reputation’ Obsolete?
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore

21. As designers, what can we learn from all of this?
What kind of community do you have (or are you trying to foster)?
When and Why to use Pos/Neg/Mixed/Hybrid Reputation Systems?
What behavior(s) do you want to encourage, reward, punish?
Consider the “unintended consequences” of implicit information
Just because you build a system to be interpreted a certain way doesn’t mean that the user will agree…
Others?
9/17/2018
Computer-Mediated Communication — Cheshire & Fiore