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Evolution of Wikipedia (WI 2006 Hong Kong)
 

Evolution of Wikipedia (WI 2006 Hong Kong)

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    Evolution of Wikipedia (WI 2006 Hong Kong) Evolution of Wikipedia (WI 2006 Hong Kong) Presentation Transcript

    • The Growth of Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates The Growth of Wikipedia: The evolution of the hyperlinks link and temporal analysis Macroscopic structure of the Wikigraph Preferential D. Donato1,2 attachment in the growth of Joint work with: L.S. Buriol1 , L. Becchetti1 , A. Capocci3 , social networks C. Castillo1,2 , F. Colaiori1 , G. Caldarelli1,3 Concluding remarks V.D.P.Servedio1,3 1. Universit` di Roma “La Sapienza” – Roma, Italy a 2. Yahoo! Research Barcelona – Catalunya, Spain 3. Centro Studi e Ricerche E. Fermi – Roma, Italy
    • The Growth of Wikipedia Wikipedia 1 Wikipedia The growth of Wikipedia The growth of Wikipedia 2 The dynamics of the updates The dynamics of the updates The evolution of 3 the hyperlinks Macroscopic structure of the The evolution of the hyperlinks 4 Wikigraph Preferential attachment in the growth of Macroscopic structure of the Wikigraph 5 social networks Concluding remarks Preferential attachment in the growth of social networks 6 Concluding remarks 7
    • The Growth of Wikipedia Wikipedia The growth of Wikipedia Wikipedia 1 The dynamics of The growth of Wikipedia 2 the updates The dynamics of the updates 3 The evolution of the hyperlinks The evolution of the hyperlinks 4 Macroscopic structure of the 5 Macroscopic structure of the Wikigraph Wikigraph Preferential attachment in the 6 Preferential attachment in growth of social networks the growth of Concluding remarks 7 social networks Concluding remarks
    • The Growth of Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Wikipedia Wikipedia A Nature investigation aimed to find if Wikipedia is an The growth of authoritative source of information with respect to established Wikipedia The dynamics of sources as Encyclopedia Britannica. the updates Among 42 entries tested, the difference in accuracy was not The evolution of the hyperlinks particularly great: Macroscopic the average science entry in Wikipedia contained around structure of the Wikigraph four inaccuracies; Preferential attachment in the one in Britannica, about three. the growth of social networks On the other hand the articles on Wikipedia are longer on Concluding average than those of Britannica. This accounts for a lower remarks rate of errors in Wikipedia (Nature 438, 900-901; 2005).
    • The Growth of Why studying Wikipedia? Wikipedia sociological reasons: the encyclopedia collects pages written by a Wikipedia number of indipendent and heterogeneous The growth of Wikipedia individuals. Each of them autonomously decides The dynamics of about the content of the articles with the only the updates constraint of a prefixed layout. The autonomy is a The evolution of common feature of the content creation in the Web. the hyperlinks The Wikipedia authors community is formed by Macroscopic structure of the members whose only wish is to make available to the Wikigraph world concepts and topics that they consider Preferential attachment in meaningful. In some sense, tracing the evolution of the growth of the Wikipedia subsets should mirror the develop of social networks significant trends within each linguistic community. Concluding remarks
    • The Growth of Why studying Wikipedia? Wikipedia sociological reasons: the encyclopedia collects pages written by a Wikipedia number of indipendent and heterogeneous The growth of Wikipedia individuals. Each of them autonomously decides The dynamics of about the content of the articles with the only the updates constraint of a prefixed layout. The autonomy is a The evolution of common feature of the content creation in the Web. the hyperlinks The Wikipedia authors community is formed by Macroscopic structure of the members whose only wish is to make available to the Wikigraph world concepts and topics that they consider Preferential attachment in meaningful. In some sense, tracing the evolution of the growth of the Wikipedia subsets should mirror the develop of social networks significant trends within each linguistic community. Concluding remarks generation on time: Wikipedia provides time information associated with nodes. Moreover, it provides old information: time information for the creation and the modifications for each page on the dataset.
    • The Growth of Why studying Wikipedia? Wikipedia sociological reasons: the encyclopedia collects pages written by a Wikipedia number of indipendent and heterogeneous The growth of Wikipedia individuals. Each of them autonomously decides The dynamics of about the content of the articles with the only the updates constraint of a prefixed layout. The autonomy is a The evolution of common feature of the content creation in the Web. the hyperlinks The Wikipedia authors community is formed by Macroscopic structure of the members whose only wish is to make available to the Wikigraph world concepts and topics that they consider Preferential attachment in meaningful. In some sense, tracing the evolution of the growth of the Wikipedia subsets should mirror the develop of social networks significant trends within each linguistic community. Concluding remarks generation on time: Wikipedia provides time information associated with nodes. Moreover, it provides old information: time information for the creation and the modifications for each page on the dataset. independency of external links: Wikipedia articles link mainly to articles on the same dataset.
    • The Growth of Summarizing Wikipedia We have available all the history of growth, so that we Wikipedia can study the evolution The growth of Wikipedia The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Summarizing Wikipedia We have available all the history of growth, so that we Wikipedia can study the evolution The growth of Wikipedia large, compressed XML file containing information about pages The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Summarizing Wikipedia We have available all the history of growth, so that we Wikipedia can study the evolution The growth of Wikipedia large, compressed XML file containing information about pages The dynamics of the updates inside each page, information about all the revisions the The evolution of page has undergo. the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Summarizing Wikipedia We have available all the history of growth, so that we Wikipedia can study the evolution The growth of Wikipedia large, compressed XML file containing information about pages The dynamics of the updates inside each page, information about all the revisions the The evolution of page has undergo. the hyperlinks for each revision, the time stamp, author, editorial Macroscopic structure of the comment and full text of the version of the page is Wikigraph available. Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Summarizing Wikipedia We have available all the history of growth, so that we Wikipedia can study the evolution The growth of Wikipedia large, compressed XML file containing information about pages The dynamics of the updates inside each page, information about all the revisions the The evolution of page has undergo. the hyperlinks for each revision, the time stamp, author, editorial Macroscopic structure of the comment and full text of the version of the page is Wikigraph available. Preferential we generated 17 snapshots of the Web graph very 3 attachment in the growth of months, starting from January 1st, 2002 (14,247 articles) social networks until April 1st, 2006 (1,064,757 articles). Concluding remarks
    • The Growth of Summarizing Wikipedia We have available all the history of growth, so that we Wikipedia can study the evolution The growth of Wikipedia large, compressed XML file containing information about pages The dynamics of the updates inside each page, information about all the revisions the The evolution of page has undergo. the hyperlinks for each revision, the time stamp, author, editorial Macroscopic structure of the comment and full text of the version of the page is Wikigraph available. Preferential we generated 17 snapshots of the Web graph very 3 attachment in the growth of months, starting from January 1st, 2002 (14,247 articles) social networks until April 1st, 2006 (1,064,757 articles). Concluding remarks We have an example of a social network of huge size
    • The Growth of Summarizing Wikipedia We have available all the history of growth, so that we Wikipedia can study the evolution The growth of Wikipedia large, compressed XML file containing information about pages The dynamics of the updates inside each page, information about all the revisions the The evolution of page has undergo. the hyperlinks for each revision, the time stamp, author, editorial Macroscopic structure of the comment and full text of the version of the page is Wikigraph available. Preferential we generated 17 snapshots of the Web graph very 3 attachment in the growth of months, starting from January 1st, 2002 (14,247 articles) social networks until April 1st, 2006 (1,064,757 articles). Concluding remarks We have an example of a social network of huge size We can compare the system produced by users of different language, thereby measuring the effect of different cultures.
    • The Growth of Summarizing Wikipedia We have available all the history of growth, so that we Wikipedia can study the evolution The growth of Wikipedia large, compressed XML file containing information about pages The dynamics of the updates inside each page, information about all the revisions the The evolution of page has undergo. the hyperlinks for each revision, the time stamp, author, editorial Macroscopic structure of the comment and full text of the version of the page is Wikigraph available. Preferential we generated 17 snapshots of the Web graph very 3 attachment in the growth of months, starting from January 1st, 2002 (14,247 articles) social networks until April 1st, 2006 (1,064,757 articles). Concluding remarks We have an example of a social network of huge size We can compare the system produced by users of different language, thereby measuring the effect of different cultures. We can study Wikipedia as a case study for the World Wide Web [Buriol et al., 2005]
    • The Growth of Wikipedia Wikipedia The growth of Wikipedia Wikipedia 1 The dynamics of The growth of Wikipedia 2 the updates The dynamics of the updates 3 The evolution of the hyperlinks The evolution of the hyperlinks 4 Macroscopic structure of the 5 Macroscopic structure of the Wikigraph Wikigraph Preferential attachment in the 6 Preferential attachment in growth of social networks the growth of Concluding remarks 7 social networks Concluding remarks
    • The Growth of The growth of Wikipedia Wikipedia (a) Articles (b) Updates Wikipedia Number of updates (thousands) Number of articles (thousands) 1200 9000 Actual Actual The growth of 8000 6.2% monthly growth 11% monthly growth 1000 7000 Wikipedia 800 6000 5000 600 4000 The dynamics of 400 3000 the updates 2000 200 1000 0 0 The evolution of Jan Jan Jan Jan Jan Jan Jan Jan Jan Jan ’02 ’03 ’04 ’05 ’06 ’02 ’03 ’04 ’05 ’06 the hyperlinks Snapshot Snapshot (c) Visitors (d) Editors Macroscopic structure of the Wikigraph 35000 900 Number of users (thousands) Actual Actual Weekly Reach (millions) 800 30000 6.2% monthly growth 4.7% monthly growth 700 Preferential 25000 600 20000 attachment in 500 400 15000 the growth of 300 10000 200 social networks 5000 100 0 0 Concluding Jan Jan Jan Jan Jan Jan Jan Jan Jan ’03 ’04 ’05 ’06 ’02 ’03 ’04 ’05 ’06 remarks Snapshot Snapshot In the last 3 years: The number of articles is doubling itself in size every year, i.e. a 6.2% montly growth. The number of updates has been growing at a rate of 11.3% per month. The number of different visitors and different editors have also been growing at a fast peace.
    • The Growth of Size of the articles Wikipedia Wikipedia The growth of Wikipedia 7.0 The dynamics of Average page length [KB] Created: the updates Before Jan’03 6.0 The evolution of During 2003 the hyperlinks 5.0 During 2004 Macroscopic During 2005 structure of the 4.0 Wikigraph 3.0 Preferential attachment in the growth of 2.0 social networks 1.0 Concluding remarks Jan Jan Jan Jan ’03 ’04 ’05 ’06 Time Individual articles have become longer, growing linearly during the last two years at a rate of 1 KB of text every 6-8 months.
    • The Growth of Wikipedia Wikipedia The growth of Wikipedia Wikipedia 1 The dynamics of The growth of Wikipedia 2 the updates The dynamics of the updates 3 The evolution of the hyperlinks The evolution of the hyperlinks 4 Macroscopic structure of the 5 Macroscopic structure of the Wikigraph Wikigraph Preferential attachment in the 6 Preferential attachment in growth of social networks the growth of Concluding remarks 7 social networks Concluding remarks
    • The Growth of Pages Updates Wikipedia Wikipedia The growth of Wikipedia 106 106 The dynamics of Actual Actual the updates 105 105 Power−law (γ=2.07) Power−law (γ=2.07) Number of Articles Number of Articles The evolution of 104 104 the hyperlinks 3 103 10 Macroscopic 2 102 10 structure of the Wikigraph 101 101 100 100 Preferential 1 10 100 1000 10000 1 10 100 1000 attachment in the growth of Number of Changes Number of Different Editors social networks The updates might be related to page views Concluding remarks
    • The Growth of Pages Updates Wikipedia Wikipedia The growth of Wikipedia 106 106 The dynamics of Actual Actual the updates 105 105 Power−law (γ=2.07) Power−law (γ=2.07) Number of Articles Number of Articles The evolution of 104 104 the hyperlinks 3 103 10 Macroscopic 2 102 10 structure of the Wikigraph 101 101 100 100 Preferential 1 10 100 1000 10000 1 10 100 1000 attachment in the growth of Number of Changes Number of Different Editors social networks The updates might be related to page views Concluding remarks There is a prominent link to see the last 50 changes plus the option to “watch” an article, to receive alerts when it is changed
    • The Growth of Editors’ behavior Wikipedia Wikipedia 7,5% of the articles have a single editor. The growth of Wikipedia The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Editors’ behavior Wikipedia Wikipedia 7,5% of the articles have a single editor. The growth of Wikipedia 50% of the articles have more than 7 different editors. The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Editors’ behavior Wikipedia Wikipedia 7,5% of the articles have a single editor. The growth of Wikipedia 50% of the articles have more than 7 different editors. The dynamics of the updates 5% of the articles have more than 50 different editors The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Editors’ behavior Wikipedia Wikipedia 7,5% of the articles have a single editor. The growth of Wikipedia 50% of the articles have more than 7 different editors. The dynamics of the updates 5% of the articles have more than 50 different editors The evolution of the hyperlinks Fraction of Articles Updated Macroscopic 30 1 structure of the 0.9 25 Updates per User Wikigraph 0.8 20 0.7 Preferential 15 attachment in 0.6 10 the growth of 0.5 social networks 5 0.4 Concluding 0 0.3 remarks Jan Jan Jan Jan Jan Jan Jan Jan Jan Jan ’02 ’03 ’04 ’05 ’06 ’02 ’03 ’04 ’05 ’06 Time Time
    • The Growth of Editors’ behavior Wikipedia Wikipedia 7,5% of the articles have a single editor. The growth of Wikipedia 50% of the articles have more than 7 different editors. The dynamics of the updates 5% of the articles have more than 50 different editors The evolution of the hyperlinks Fraction of Articles Updated Macroscopic 30 1 structure of the 0.9 25 Updates per User Wikigraph 0.8 20 0.7 Preferential 15 attachment in 0.6 10 the growth of 0.5 social networks 5 0.4 Concluding 0 0.3 remarks Jan Jan Jan Jan Jan Jan Jan Jan Jan Jan ’02 ’03 ’04 ’05 ’06 ’02 ’03 ’04 ’05 ’06 Time Time The fraction of articles that are updated is very high. Over 80%of the articles are updated in the three-months period we are considering for these snapshots.
    • The Growth of Reverts Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Reverts Wikipedia Wikipedia The growth of Wikipedia The Reverts are one-click operations that take an article back The dynamics of the updates to a previous version. The evolution of This is done mostly to fight vandalism. the hyperlinks Macroscopic structure of the 7% 9% Wikigraph Double Reverts per Revert 8% 6% Reverts per Update 7% Preferential 5% 6% attachment in 4% 5% the growth of 4% 3% social networks 3% 2% 2% Concluding 1% 1% remarks 0% 0% Jan Jan Jan Jan Jan Jan Jan Jan Jan Jan ’02 ’03 ’04 ’05 ’06 ’02 ’03 ’04 ’05 ’06 Snapshot Snapshot
    • The Growth of Clustering Wikipedia We clustered by the k-means algorithm the “update profile” Wikipedia of a set of pages using the euclidian distance among the The growth of Wikipedia update vectors. The dynamics of the updates Cluster 1 Cluster 4 The evolution of 1.0 1.0 the hyperlinks Fraction of Updates Fraction of Updates 0.8 0.8 Macroscopic structure of the 0.6 0.6 Wikigraph 0.4 0.4 Preferential attachment in 0.2 0.2 the growth of social networks 0.0 0.0 Jan Jan Jan Jan Jan Jan Concluding ’04 ’05 ’06 ’04 ’05 ’06 remarks Cluster 2 Cluster 3 1.0 1.0 Fraction of Updates Fraction of Updates 0.8 0.8 0.6 0.6 0.4 0.4 0.2 0.2 0.0 0.0
    • The Growth of Wikipedia Wikipedia The growth of Wikipedia Wikipedia 1 The dynamics of The growth of Wikipedia 2 the updates The dynamics of the updates 3 The evolution of the hyperlinks The evolution of the hyperlinks 4 Macroscopic structure of the 5 Macroscopic structure of the Wikigraph Wikigraph Preferential attachment in the 6 Preferential attachment in growth of social networks the growth of Concluding remarks 7 social networks Concluding remarks
    • The Growth of Degree Distribution Wikipedia The Degree shows fat tails that can be approximated by a Wikipedia power-law function of the kind P(K ) ∼ k1γ , for γ > 1. We The growth of Wikipedia found γ = 2.00, similar to the value that has been observed in The dynamics of the indegree distribution of Web graphs (2.1) the updates [Broder et al., 2000, Donato et al., 2004]. The evolution of the hyperlinks Macroscopic 106 106 Actual structure of the Actual Power−law (γ=2.07) 105 Wikigraph 105 Power−law (γ=2.46) Number of Articles Number of Articles 104 Preferential 104 attachment in 3 103 10 the growth of social networks 2 102 10 Concluding 1 101 10 remarks 0 100 10 1 10 100 1000 10000 1 10 100 1000 10000 Number of In−links Number of Out−links The power-law exponent of the indegree has remained remarkably constant even when the graph has grown substantially in the studied period (from ≈14,000 articles to ≈1,000,000).
    • The Growth of Average Outdegree Wikipedia The Wikipedia graph is becoming denser. During the last two Wikipedia and a half years, articles have grown from an average of 7 The growth of Wikipedia out-links per article to an average of 16 (on average one new The dynamics of reference every 100 days). the updates The evolution of the hyperlinks 18 Actual Macroscopic 16 structure of the 1 new link every 100 days Wikigraph 14 Out−degree Preferential attachment in 12 the growth of social networks 10 Concluding 8 remarks 6 4 Jan Jan Jan Jan Jan ’02 ’03 ’04 ’05 ’06 Time This is a trend observed in other social networks by Leskovec et al. [Leskovec et al., 2005].
    • The Growth of PageRank Wikipedia Wikipedia The tail of the distribution of PageRank for the usual parameter The growth of setting follows a power-law with exponent γ = 2.1 Wikipedia [Donato et al., 2004]. The dynamics of the updates The evolution of 0.8 the hyperlinks PageRank / In−Degree 0.7 Macroscopic structure of the 0.6 Correlation Wikigraph 0.5 Preferential 0.4 attachment in 0.3 the growth of 0.2 social networks 0.1 Concluding remarks 0.0 Jan Jan Jan Jan Jan ’02 ’03 ’04 ’05 ’06 Time The correlation between PageRank and indegree is very low in Web graphs. Interestingly, in the Wikigraph this correlation has increased in the last years, basically following the densification of the graph.
    • The Growth of Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates The evolution of Is the low PageRank/indegree correlation the hyperlinks Macroscopic observed in Web graph a transient phenomenon? structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Other microscopic measures Wikipedia Wikipedia The growth of 0.30 Wikipedia Clustering coefficient 0.28 The dynamics of Edge reciprocity 0.26 the updates 0.24 Coefficient The evolution of the hyperlinks 0.22 0.20 Macroscopic structure of the 0.18 Wikigraph 0.16 Preferential 0.14 attachment in the growth of 0.12 social networks 0.10 Concluding Jan Jan Jan Jan Jan remarks ’02 ’03 ’04 ’05 ’06 Time The Wikigraph seems to have stabilized in the last years the average clustering coefficient is roughly 0.23
    • The Growth of Other microscopic measures Wikipedia Wikipedia The growth of 0.30 Wikipedia Clustering coefficient 0.28 The dynamics of Edge reciprocity 0.26 the updates 0.24 Coefficient The evolution of the hyperlinks 0.22 0.20 Macroscopic structure of the 0.18 Wikigraph 0.16 Preferential 0.14 attachment in the growth of 0.12 social networks 0.10 Concluding Jan Jan Jan Jan Jan remarks ’02 ’03 ’04 ’05 ’06 Time The Wikigraph seems to have stabilized in the last years the average clustering coefficient is roughly 0.23 the fraction of reciprocal edges is about about 0.13.
    • The Growth of Assortativity Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks As regard the assortativity (as measured by the average degree of the neighbours of a vertex with degree k) there is no evidence of any assortative behaviour.
    • The Growth of Wikipedia Wikipedia The growth of Wikipedia Wikipedia 1 The dynamics of The growth of Wikipedia 2 the updates The dynamics of the updates 3 The evolution of the hyperlinks The evolution of the hyperlinks 4 Macroscopic structure of the 5 Macroscopic structure of the Wikigraph Wikigraph Preferential attachment in the 6 Preferential attachment in growth of social networks the growth of Concluding remarks 7 social networks Concluding remarks
    • The Growth of Connectivity Wikipedia The Wikigraph is almost entirely (weakly) connected. Over Wikipedia 98.5% of the articles are connected to each other. The growth of Wikipedia The dynamics of 70% 70% the updates IN 60% Size of IN and OUT OUT 60% The evolution of Size of CORE 50% the hyperlinks 50% 40% Macroscopic 30% 40% structure of the 20% Wikigraph 30% 10% Preferential 20% 0% attachment in Jan Jan Jan Jan Jan Jan Jan Jan Jan Jan the growth of ’02 ’03 ’04 ’05 ’06 ’02 ’03 ’04 ’05 ’06 Time Time social networks Concluding the CORE component is getting larger. remarks
    • The Growth of Connectivity Wikipedia The Wikigraph is almost entirely (weakly) connected. Over Wikipedia 98.5% of the articles are connected to each other. The growth of Wikipedia The dynamics of 70% 70% the updates IN 60% Size of IN and OUT OUT 60% The evolution of Size of CORE 50% the hyperlinks 50% 40% Macroscopic 30% 40% structure of the 20% Wikigraph 30% 10% Preferential 20% 0% attachment in Jan Jan Jan Jan Jan Jan Jan Jan Jan Jan the growth of ’02 ’03 ’04 ’05 ’06 ’02 ’03 ’04 ’05 ’06 Time Time social networks Concluding the CORE component is getting larger. remarks about 2/3 of the nodes belong to the larger strongly connected component of the Wikigraph, which is larger than was observed in 1999 in the Altavista crawl [Broder et al., 2000] or in 2001 in the WebBase crawl [Donato et al., 2004]
    • The Growth of Connectivity Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates The evolution of the hyperlinks Macroscopic The increase of the size of the CORE has been mostly at structure of the Wikigraph the expense of the OUT component Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Migration of articles among the components Wikipedia We study the “movement” of articles among components of Wikipedia the different components of the Wikipedia graph, The growth of Wikipedia following [Baeza-Yates and Poblete, 2004]. The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks Interestingly, the CORE and OUT components are very stable, with over 60% of the articles remaining in the same component after three months. Also, these transition probabilities have remained basically stable over different snapshots.
    • The Growth of Wikipedia Wikipedia The growth of Wikipedia Wikipedia 1 The dynamics of The growth of Wikipedia 2 the updates The dynamics of the updates 3 The evolution of the hyperlinks The evolution of the hyperlinks 4 Macroscopic structure of the 5 Macroscopic structure of the Wikigraph Wikigraph Preferential attachment in the 6 Preferential attachment in growth of social networks the growth of Concluding remarks 7 social networks Concluding remarks
    • The Growth of Preferential attachment hypothesis Wikipedia Given the history of growth one can verify the hypothesis of Wikipedia preferential attachment. This is done by means of the The growth of Wikipedia histogram P(k) who gives the number of vertices (whose The dynamics of degree is k) acquiring new connections at time t.This is the updates quantity is weighted by the factor N(t)/n(k,t) The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Modelling Wikipedia Wikipedia The growth of From these data it seems that a model in the spirit of BA Wikipedia could reproduce most of the features of the system. The dynamics of the updates Actually The evolution of the hyperlinks This network is oriented. Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Modelling Wikipedia Wikipedia The growth of From these data it seems that a model in the spirit of BA Wikipedia could reproduce most of the features of the system. The dynamics of the updates Actually The evolution of the hyperlinks This network is oriented. Macroscopic structure of the The preferential attachment in Wikipedia has a Wikigraph somewhat different nature. Here, most of the times, the Preferential attachment in edges are added between existing vertices differently from the growth of social networks the BA model. For instance, in the English version of Concluding Wikipedia a largely dominant fraction 0.883 of new edges remarks is created between two existing pages, while a smaller fraction of edges points or leaves a newly added vertex (0.026 and 0.091 respectively).
    • The Growth of Modelling Wikipedia We introduced an evolution rule, similar to other models of Wikipedia rewiring already considered. At each time step we make a The growth of Wikipedia move The dynamics of A vertex is added to the network. It is connected to the the updates The evolution of existing vertices by M oriented edges. the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Modelling Wikipedia We introduced an evolution rule, similar to other models of Wikipedia rewiring already considered. At each time step we make a The growth of Wikipedia move The dynamics of A vertex is added to the network. It is connected to the the updates The evolution of existing vertices by M oriented edges. the hyperlinks with probability R1 the edge leaves the new vertex Macroscopic structure of the pointing to an existing one chosen with probability Wikigraph proportional to its indegree; Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Modelling Wikipedia We introduced an evolution rule, similar to other models of Wikipedia rewiring already considered. At each time step we make a The growth of Wikipedia move The dynamics of A vertex is added to the network. It is connected to the the updates The evolution of existing vertices by M oriented edges. the hyperlinks with probability R1 the edge leaves the new vertex Macroscopic structure of the pointing to an existing one chosen with probability Wikigraph proportional to its indegree; Preferential attachment in the growth of with probability R2, the edge points to the new vertex, social networks and the source vertex is chosen with probability Concluding remarks proportional to its outdegree.
    • The Growth of Modelling Wikipedia We introduced an evolution rule, similar to other models of Wikipedia rewiring already considered. At each time step we make a The growth of Wikipedia move The dynamics of A vertex is added to the network. It is connected to the the updates The evolution of existing vertices by M oriented edges. the hyperlinks with probability R1 the edge leaves the new vertex Macroscopic structure of the pointing to an existing one chosen with probability Wikigraph proportional to its indegree; Preferential attachment in the growth of with probability R2, the edge points to the new vertex, social networks and the source vertex is chosen with probability Concluding remarks proportional to its outdegree. Finally, with probability R3 = 1 - R1 - R2 the edge is added between existing vertices: the source vertex is chosen with probability proportional to the outdegree, while the destination vertex is chosen with probability proportional to the indegree.
    • The Growth of Modelling Wikipedia Wikipedia The growth of Wikipedia The model can be solved analytically: The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks We can use for the model the empirical values of R1=0.026 R2=0.091 R3=0.883 Already measured for the English version of Wikigraph
    • The Growth of Wikipedia Wikipedia The growth of Wikipedia Wikipedia 1 The dynamics of The growth of Wikipedia 2 the updates The dynamics of the updates 3 The evolution of the hyperlinks The evolution of the hyperlinks 4 Macroscopic structure of the 5 Macroscopic structure of the Wikigraph Wikigraph Preferential attachment in the 6 Preferential attachment in growth of social networks the growth of Concluding remarks 7 social networks Concluding remarks
    • The Growth of Signs of transient regime (growth) Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates The number of articles, updates, visitors and editors is The evolution of still growing exponentially. the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Signs of transient regime (growth) Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates The number of articles, updates, visitors and editors is The evolution of still growing exponentially. the hyperlinks Macroscopic The size of articles is still growing linearly. structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Signs of transient regime (growth) Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates The number of articles, updates, visitors and editors is The evolution of still growing exponentially. the hyperlinks Macroscopic The size of articles is still growing linearly. structure of the Wikigraph The number of links per article is also growing linearly, Preferential slowly than the amount of text. attachment in the growth of social networks Concluding remarks
    • The Growth of Signs of transient regime (growth) Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates The number of articles, updates, visitors and editors is The evolution of still growing exponentially. the hyperlinks Macroscopic The size of articles is still growing linearly. structure of the Wikigraph The number of links per article is also growing linearly, Preferential slowly than the amount of text. attachment in the growth of The number of reverts is growing slowly, which may social networks Concluding signal more vandalism, but the number of double reverts remarks (revert wars) has stabilized.
    • The Growth of Signs of permanent regime (maturity) Wikipedia Wikipedia The growth of There is a clear power-law distribution of the indegree Wikipedia The dynamics of and outdegree. the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Signs of permanent regime (maturity) Wikipedia Wikipedia The growth of There is a clear power-law distribution of the indegree Wikipedia The dynamics of and outdegree. the updates The average edits per user has been mostly constant in The evolution of the hyperlinks the last two years. Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Signs of permanent regime (maturity) Wikipedia Wikipedia The growth of There is a clear power-law distribution of the indegree Wikipedia The dynamics of and outdegree. the updates The average edits per user has been mostly constant in The evolution of the hyperlinks the last two years. Macroscopic structure of the There is a high correlation between PageRank and Wikigraph indegree, indicating that the microscopic connectivity of Preferential attachment in the encyclopedia resembles its mesoscopic the growth of social networks Concluding remarks
    • The Growth of Signs of permanent regime (maturity) Wikipedia Wikipedia The growth of There is a clear power-law distribution of the indegree Wikipedia The dynamics of and outdegree. the updates The average edits per user has been mostly constant in The evolution of the hyperlinks the last two years. Macroscopic structure of the There is a high correlation between PageRank and Wikigraph indegree, indicating that the microscopic connectivity of Preferential attachment in the encyclopedia resembles its mesoscopic the growth of social networks The clustering coefficient and edge reciprocity of links Concluding have remained basically constant during the last two remarks years.
    • The Growth of Signs of permanent regime (maturity) Wikipedia Wikipedia The growth of There is a clear power-law distribution of the indegree Wikipedia The dynamics of and outdegree. the updates The average edits per user has been mostly constant in The evolution of the hyperlinks the last two years. Macroscopic structure of the There is a high correlation between PageRank and Wikigraph indegree, indicating that the microscopic connectivity of Preferential attachment in the encyclopedia resembles its mesoscopic the growth of social networks The clustering coefficient and edge reciprocity of links Concluding have remained basically constant during the last two remarks years. Over 2/3 of the articles belong now to the larger strongly connected component.
    • The Growth of Wikipedia Wikipedia Thank you! The growth of Wikipedia The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Wikipedia Wikipedia Thank you! The growth of Wikipedia The dynamics of the updates The evolution of the hyperlinks Macroscopic structure of the Wikigraph Preferential attachment in the growth of social networks Concluding remarks
    • The Growth of Wikipedia Baeza-Yates, R. and Poblete, B. (2004). Dynamics of the chilean web structure. Wikipedia In Proc. of the 3rd WebDyn. The growth of Wikipedia Broder, A., Kumar, R., Maghoul, F., Raghavan, P., The dynamics of the updates Rajagopalan, S., Stata, R., Tomkins, A., and Wiener, J. The evolution of (2000). the hyperlinks Graph structure in the web: Experiments and models. Macroscopic structure of the In Proc. of the 9th WWW, pages 309–320. ACM Press. Wikigraph Preferential Buriol, L. S., Donato, D., Leonardi, S., and Millozzi, S. (2005). attachment in the growth of social networks Link and temporal analysis of wikigraphs. Concluding Technical report, DELIS – Dynamically Evolving, Large-Scale remarks Information Systems. Donato, D., Laura, L., Leonardi, S., and Millozzi, S. (2004). Large scale properties of the webgraph. European Physical Journal B, 38:239–243.
    • The Growth of Wikipedia Wikipedia The growth of Wikipedia The dynamics of the updates Leskovec, J., Kleinberg, J., and Faloutsos, C. (2005). The evolution of the hyperlinks Graphs over time: densification laws, shrinking diameters and Macroscopic possible explanations. structure of the Wikigraph In Proc. of the 11th KDD, pages 177–187. ACM Press. Preferential attachment in the growth of social networks Concluding remarks