1. COLOR TESTCOLOR TESTCOLOR TESTCOLOR TEST

2. Engineering Social Networks Nicole Immorlica, Northwestern University

5. spread of disease.

6. diffusion of products.

7. networks: exogenous, endogenous, … or designed?

8. example: designing networks to engineer diversity.

9. initially,

10. initially, a regular directed graph blue and yellow nodes

11. at time t,

12. at time t, link to mR nodes at random 1. 2. link to mS nodes via color- biased searching

13. parameters: q, fraction of blue to yellow mR, # of random neighbors mS, # of biased neighbors

14. question: what is the diversity as a function of q, mR, and mS?

15. argo tea observations: (joint with B. Lucier and B. Rogers) steady-state diversity is independent of mS 1. 2. speed of convergence is function of mR/mS

16. lesson: a centralized designer can enforce diversity by insisting that people have a few random friends.

17. killer app #1: Schelling model of segregation

20. question: (joint with Kleinberg2 and Sinclair) can we decrease segregation by teaching tolerance? who should we target?

21. killer app #2, 3, 4, …: (half-baked) poverty traps information cascades fostering collaboration

22. killer app #n?