From: "Ivona Bezakova" Date: Thu, 18 Apr 2002 23:48:26 -0500 The Small-World Phenomenon: An Algorithmic Perspective [Jon Kleinberg] 1. State the main contribution of the paper: The author proposes a family of graphs to model the small-world phenomenon and discusses its properties. This family is a generalization of the preceding approaches and after tuning its parameters it can be used to model a successful local routing algorithm (as opposed to just pure existence of a short path). More precisely, the expected length of the routing path used by this algorithm is poly-logarithmic in the number of vertices. This statement is “if and only if”, i.e. if the parameters are chosen differently, the expected routing path using any local routing method is at least polynomial. 2. Critique the main contribution.  a. Rate the significance of the paper: 4-5. This theoretical study is related to different contexts – experimental data ranging from sociology to world-wide-web (?-see below). The results are simple and strong. b. Rate how convincing the methodology is: 4-5. Well-written. c. What is the most important limitation of the approach? 3. What are the three strongest and/or most interesting ideas in the paper? – The model itself, it seems to be natural and still quite intriguing. – Ability to analyze the model (in so simple way!) and the strength of the results. – Well-written for any type of audience. 4. What are the three most striking weaknesses in the paper? – Proofs without restating Theorems to-be-proven. – World-wide-web is mentioned in the abstract but no further evidence of it being a small-world is given. 5. Name three questions that you would like to ask the authors? – Is there some well-established “definition” of the small-world phenomenon? [Or is it just the ability of finding short paths using local strategies?] 6. Detail an interesting extension to the work not mentioned in the future work section. See 7. Experimentally verify this model as a model for the Internet. 7. Optional comments on the paper that you’d like to see discussed in class. The study relates to small-world w.r.t. people’s relationships. The model is natural in this context, people tend to know the best the people living in close vicinity. How does it correspond to Internet, or the web-linking structure?