The DOI matches its Crossref record; 21 of the 21 references it cites were found in a registry or an index.
Four degrees of separation
Abstract
Frigyes Karinthy, in his 1929 short story "Láncszemek" (in English, "Chains") suggested that any two persons are distanced by at most six friendship links.1 Stanley Milgram in his famous experiments challenged people to route postcards to a fixed recipient by passing them only through direct acquaintances. Milgram found that the average number of intermediaries on the path of the postcards lay between 4:4 and 5:7, depending on the sample of people chosen. We report the results of the first world-scale social-network graph-distance computations, using the entire Facebook network of active users (≈ 721 million users, ≈ 69 billion friendship links). The average distance we observe is 4:74, corresponding to 3:74 intermediaries or "degrees of separation", prompting the title of this paper. More generally, we study the distance distribution of Facebook and of some interesting geographic subgraphs, looking also at their evolution over time. The networks we are able to explore are almost two orders of magnitude larger than those analysed in the previous literature. We report detailed statistical metadata showing that our measurements (which rely on probabilistic algorithms) are very accurate.
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Cites
The small-world problem: (400002009-005)
Milgram, S. (1967) · PsycEXTRA Dataset · doi:10.1037/e400002009-005 · Cited by 4,790
A leisurely look at the bootstrap, the jackknife, and cross-validation
Efron, B., & Gong, G. (1983) · The American Statistician · doi:10.1080/00031305.1983.10483087 · Cited by 3,229
Broder, A., Kumar, R., Maghoul, F., Raghavan, P., Rajagopalan, S., Stata, R., Tomkins, A., & Wiener, J. (2000) · Computer Networks · doi:10.1016/s1389-1286(00)00083-9 · Cited by 2,810
Graph evolution: Densification and shrinking diameters
Leskovec, J., Kleinberg, J., & Faloutsos, C. (2007) · ACM Transactions on Knowledge Discovery from Data · doi:10.1145/1217299.1217301 · Cited by 2,461
The small-world phenomenon: an algorithmic perspective
Kleinberg, J. (2000) · Proceedings of the thirty-second annual ACM symposium on Theory of computing · doi:10.1145/335305.335325 · Cited by 1,882
An Experimental Study of the Small World Problem
Travers, J., & Milgram, S. (1969) · Sociometry · doi:10.2307/2786545 · Cited by 1,863
Kleinberg, J. M. (2000) · Nature · doi:10.1038/35022643 · Cited by 1,737
The webgraph framework I: compression techniques
Boldi, P., & Vigna, S. (2004) · Proceedings of the 13th international conference on World Wide Web · doi:10.1145/988672.988752 · Cited by 1,201
Self-citationGeographic routing in social networks
Liben-Nowell, D., Novak, J., Kumar, R., Raghavan, P., & Tomkins, A. (2005) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.0503018102 · Cited by 838
Find me if you can: improving geographical prediction with social and spatial proximity
Backstrom, L., Sun, E., & Marlow, C. (2010) · Proceedings of the 19th international conference on World wide web · doi:10.1145/1772690.1772698 · Cited by 705
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A Review of Facebook Research in the Social Sciences
Wilson, R. E., Gosling, S. D., & Graham, L. T. (2012) · Perspectives on Psychological Science · doi:10.1177/1745691612442904 · Cited by 1,226
Structure and dynamics of molecular networks: A novel paradigm of drug discovery
Csermely, P., Korcsmáros, T., Kiss, H. J. M., London, G., & Nussinov, R. (2013) · Pharmacology & Therapeutics · doi:10.1016/j.pharmthera.2013.01.016 · Cited by 892
The Anatomy of the Facebook Social Graph
Ugander, J., Karrer, B., Backstrom, L., & Marlow, C. (2011) · arXiv · doi:10.48550/arxiv.1111.4503 · Cited by 819
Self-citationTwenge, J. M., Martin, G. N., & Spitzberg, B. H. (2019) · Psychology of Popular Media Culture · doi:10.1037/ppm0000203 · Cited by 703
Web data extraction, applications and techniques: A survey
Ferrara, E., De Meo, P., Fiumara, G., & Baumgartner, R. (2014) · Knowledge-Based Systems · doi:10.1016/j.knosys.2014.07.007 · Cited by 396
Metadata
- Authors
- Backstrom, L., Boldi, P., Rosa, M., Ugander, J., & Vigna, S.
- Venue
- Proceedings of the 4th Annual ACM Web Science Conference
- Publisher
- ACM
- Published
- 2012-06-22
- Pages
- 33-42
- OpenAlex
- W2111023939
- Cited by
- 567
- References
- 21
- FWCI
- 67.30
- Type
- conference paper
- Language
- en
- Open access
- closed
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