Measuring wiki viability - CRESScress.soc.surrey.ac.uk/web/sites/.../presentation/... · wikis belonging to the clean dataset. Measuring wiki viability D. Taraborelli. Viable wikisWiki

Viable wikis Wiki dynamics Wiki growth enhancers and regulators Research directions

Measuring wiki viabilityAn empirical assessment of the social dynamics

of a large sample of wiki-based communities

Dario Taraborelli

[email protected]

CRESS SeminarNovember 4, 2008

Measuring wiki viability D. Taraborelli


What factors determine the viability of onlinecommunities?

I Content-based online communities face a variety of risks:

I content explosion

I population extinction

I low user turnover/high rate of user dropout

I insufficient/unmanageable rate of user activity

I Typical solution: best practices



What factors determine the viability of onlinecommunities?

I Content-based online communities face a variety of risks:

I content explosion

I population extinction

I low user turnover/high rate of user dropout

I insufficient/unmanageable rate of user activity

I Typical solution: best practices



What factors determine the viability of onlinecommunities? (2)

“Wikipatterns is a toolbox of patterns and anti-patterns. Lookingto spur wiki adoption? Want to grow from 10 users to 100, or1,000? Applying patterns that help guide the growth of content,and recognizing anti-patterns that might hinder growth, cangive your wiki the greatest chance of success”




I Wikipedia-centered literature on wiki dynamics

I Scarcity of data on the temporal dynamics of suchcommunities

I Lack of tools to make empirically grounded predictionson what determines the extinction or survival of an onlinecommunity

I Little guidance for policy makers on the governance ofsuch communities
























Overview

Goal: Identify factors that affect the dynamics of a large sampleof wiki-based communities.

1. Wiki dynamics: methodology

2. Results: growth enhancers and regulators

3. Research directions and conclusions



Method: Wiki activity scheme

P1 P2 P3 P4

ADMINS

USERS

EDITS

PAGES

A1 A2

U1 U2 U4 U5

U3



Method: dataset

I Data source

Growth data tracked over an 8-month span from 11, 500+MediaWikis

I Selected sample

360 wikis, with an initial population between 400 and20, 000 users, restricted to hosters with reliable data, andwith no major discontinuity in daily change rates.

I VariablesI population size (U)I content size (P)I admin population (A)I edits (E)I access control (R)



Method: dataset

I Data source


I Selected sample





Method: dataset

I Data source


I Selected sample





Method: Indicators considered

descriptive indicators

I user activity, i.e. the proportion of edits per user (E/U)I user density, i.e. the proportion of users per page (U/P)I edit density, i.e. the proportion of edits per page (E/P).

governance factors

I administrator ratio, i.e. the proportion of users with adminstatus (A/U)

I administrator density, i.e. the proportion of admins perpage (A/P)

I editing permission (R).






governance factors









governance factors






Method: Analysis

1. Sort wikis according to each of these indicators (e.g. editdensity)

edit density

2. Aggregate wikis in bins (quantiles) of identical size (e.g.wikis with low edit density vs. wikis with high edit density)

Q1 Q2 Q3 Q4 Q5

edit density

3. Measure how each quantile performs with respect tocontent and population growth rates

Q1 Q2 Q3 Q4 Q5

edit density



Growth enhancers (1): user activity

of their population or content.

3. WIKI DYNAMICSWe assessed wiki dynamics by comparing their diverse paths withrespect to a set of independent variables. ‘Growth’ is defined interms of population and content size change: user growth GU (resp.page growth GP ) is the ratio between final and initial populations(resp. content sizes): GU = Ulast/Ufirst (resp. GP = Plast/Pfirst).Wiki dynamics were studied as a function of the variables listed inSection 2.2:

(I) DESCRIPTIVE INDICATORS, i.e. variables on which wiki ad-ministrators have no direct control: (a) user activity, i.e. theproportion of edits per user (E/U ), (b) user density, i.e. theproportion of users per page (U/P ), and (c) edit density, i.e.the proportion of edits per page (E/P ).

(II) GOVERNANCE FACTORS, variables that wiki administratorscan directly control: (a) administrator ratio, i.e. the propor-tion of users who are granted administrator status (A/U ),(b) administrator density, i.e. the proportion of administra-tors per page (A/P ), (c) editing permission (R).

For each continuous variable, instead of carrying out a delicateanalysis by dealing with clouds of points, we adopted a more in-sightful approach by dividing wikis into five quantiles, each includ-ing exactly 20% of all wikis in the clean dataset (see Table 1). We

1 2 3 4 5

Quantile of

edits per user1.0

1.1

1.2

1.3

1.4

1.5

1.6

Growth ratio

User growth

1 2 3 4 5

Quantile of

edits per user

0.95

1.00

1.05

1.10

1.15

1.20

1.25

1.30

Growth ratio

Page growth

1.1

1.11.1

1.2

1.2

1.3

1.3

1.4

1.4

1 2 3 4 51

2

3

4

Quantiles of 'edits per user'

Populationquantiles

User growth

1

1

1

1.1

1.1

1.1

1.1

1.11.2

1.2

1 2 3 4 51

2

3

4


Populationquantiles

Page growth

Figure 1: Growth landscape with respect to the proportion ofedits per user.

1 2 3 4 5

Quantile of

users per good page1.0

1.1

1.2

1.3

1.4

1.5

1.6

Growth ratio

User growth

1 2 3 4 5

Quantile of


1.05

1.10

1.15

1.20

1.25

1.30

Growth ratio

Page growth

1

1.1

1.1

1.2

1.2

1.3

1.3

1.41.4 1.5

1 2 3 4 51

2

3

4

Quantiles of 'users per good page'

Populationquantiles

User growth

1

1

1

1.1

1.1

1.1

1.1

1.2

1 2 3 4 51

2

3

4


Populationquantiles

Page growth

Figure 2: Growth landscape with respect to the proportion ofusers per good page.

then computed and compared growth ratio means over all wikis foreach quantile. Additionally, we distinguished population quantilesin order to control for user size-related effects. To this end, weplotted a growth landscape that consists of a two-dimensional rep-resentation of the various growth ratios. This representation wasapplied to all the above-mentioned variables, except for R wherethere are only two “quantiles” (0 or 1). For each variable except R,the upper graphs indicate the mean values and confidence intervals(p < 0.05) of each quantile on the variable considered, while thelower graphs show contour plots for the same variable with brighterareas corresponding to higher growth ratios.

3.1 Significant descriptive indicatorsWe found significant correlations between a number of descriptiveindicators of wiki structure and their content and population growthrates.

Figure 1 shows the effect of user activity (measured as the pro-portion of edits per user) on growth rates. The results suggest thatuser activity correlates very strongly with wiki growth, not only interms of content production (which is to a certain extent unsurpris-ing) but also new member recruitment. The effect becomes strongerwith initially more populated wikis: the more users are activelyediting, the more a wiki grows in content and population.

Figure 2 shows the impact of user density on growth. The re-sults suggest that a higher number of contributors per page does notnecessarily indicate mushrooming wikis: for an identical contentsize, we found a significant correlation between a lower number ofusers and higher growth ratios, both in content and new members.

To better visualize the effect of user density on growth, we rep-resented the dependent variables GU and GP , independent vari-

1

2

3

4

5

6

7

8

U!P

400 1000 10000 20000

10

100

1000

10000

100000

Population !users"

Content

!goodpages"

Figure 3: Phase diagram in the content/population space ofwikis belonging to the clean dataset.



Growth regulators (1): user density

of their population or content.

3. WIKI DYNAMICSWe assessed wiki dynamics by comparing their diverse paths withrespect to a set of independent variables. ‘Growth’ is defined interms of population and content size change: user growth GU (resp.page growth GP ) is the ratio between final and initial populations(resp. content sizes): GU = Ulast/Ufirst (resp. GP = Plast/Pfirst).Wiki dynamics were studied as a function of the variables listed inSection 2.2:

(I) DESCRIPTIVE INDICATORS, i.e. variables on which wiki ad-ministrators have no direct control: (a) user activity, i.e. theproportion of edits per user (E/U ), (b) user density, i.e. theproportion of users per page (U/P ), and (c) edit density, i.e.the proportion of edits per page (E/P ).

(II) GOVERNANCE FACTORS, variables that wiki administratorscan directly control: (a) administrator ratio, i.e. the propor-tion of users who are granted administrator status (A/U ),(b) administrator density, i.e. the proportion of administra-tors per page (A/P ), (c) editing permission (R).

For each continuous variable, instead of carrying out a delicateanalysis by dealing with clouds of points, we adopted a more in-sightful approach by dividing wikis into five quantiles, each includ-ing exactly 20% of all wikis in the clean dataset (see Table 1). We

1 2 3 4 5

Quantile of

edits per user1.0

1.1

1.2

1.3

1.4

1.5

1.6

Growth ratio

User growth

1 2 3 4 5

Quantile of

edits per user

0.95

1.00

1.05

1.10

1.15

1.20

1.25

1.30

Growth ratio

Page growth

1.1

1.11.1

1.2

1.2

1.3

1.3

1.4

1.4

1 2 3 4 51

2

3

4


Populationquantiles

User growth

1

1

1

1.1

1.1

1.1

1.1

1.11.2

1.2

1 2 3 4 51

2

3

4


Populationquantiles

Page growth

Figure 1: Growth landscape with respect to the proportion ofedits per user.

1 2 3 4 5

Quantile of


1.1

1.2

1.3

1.4

1.5

1.6

Growth ratio

User growth

1 2 3 4 5

Quantile of


1.05

1.10

1.15

1.20

1.25

1.30

Growth ratio

Page growth

1

1.1

1.1

1.2

1.2

1.3

1.3

1.41.4 1.5

1 2 3 4 51

2

3

4


Populationquantiles

User growth

1

1

1

1.1

1.1

1.1

1.1

1.2

1 2 3 4 51

2

3

4


Populationquantiles

Page growth

Figure 2: Growth landscape with respect to the proportion ofusers per good page.

then computed and compared growth ratio means over all wikis foreach quantile. Additionally, we distinguished population quantilesin order to control for user size-related effects. To this end, weplotted a growth landscape that consists of a two-dimensional rep-resentation of the various growth ratios. This representation wasapplied to all the above-mentioned variables, except for R wherethere are only two “quantiles” (0 or 1). For each variable except R,the upper graphs indicate the mean values and confidence intervals(p < 0.05) of each quantile on the variable considered, while thelower graphs show contour plots for the same variable with brighterareas corresponding to higher growth ratios.

3.1 Significant descriptive indicatorsWe found significant correlations between a number of descriptiveindicators of wiki structure and their content and population growthrates.

Figure 1 shows the effect of user activity (measured as the pro-portion of edits per user) on growth rates. The results suggest thatuser activity correlates very strongly with wiki growth, not only interms of content production (which is to a certain extent unsurpris-ing) but also new member recruitment. The effect becomes strongerwith initially more populated wikis: the more users are activelyediting, the more a wiki grows in content and population.

Figure 2 shows the impact of user density on growth. The re-sults suggest that a higher number of contributors per page does notnecessarily indicate mushrooming wikis: for an identical contentsize, we found a significant correlation between a lower number ofusers and higher growth ratios, both in content and new members.

To better visualize the effect of user density on growth, we rep-resented the dependent variables GU and GP , independent vari-

1

2

3

4

5

6

7

8

U!P

400 1000 10000 20000

10

100

1000

10000

100000

Population !users"

Content

!goodpages"

Figure 3: Phase diagram in the content/population space ofwikis belonging to the clean dataset.Measuring wiki viability D. Taraborelli


Wiki growth landscape (user density)

1

2

3

4

5

6

7

8U!P

400 1000 10000 20000

10

100

1000

10000

100000

Population !users"

Content

!goodpages"



Growth enhancers (2): editing permission

able U/P , and initial wiki positions Ufirst and Pfirst altogether onthe same graph, yielding a phase diagram as plotted on Fig. 3.6 Inthis diagram, each dot (light color) corresponds to a wiki in thedatabase. Each arrow corresponds to a pair of quantiles “users perpage, population”. Widths and heights are proportional to user andcontent growth ratios, respectively. The size of the arrow representsthe strength of the observed growth in content and population forwikis in a given region of the wikisphere.

This graph should be regarded as a map of a portion of the wiki-sphere, showing the expected destiny of a wiki in terms of contentand population growth as a function of its initial position in thesame space. This diagram broadly suggests that a wiki’s positionis correlated with its subsequent fate. More precisely, it illustratesthat wikis in the upper/upper-right portion of the diagram are grow-ing faster, and more interestingly it provides an overview of demo-graphic dynamics in this region of the wikisphere.

3.2 Significant governance factorsTurning to governance features, we first analyzed the effects of theadministrator density on wiki dynamics by looking at the overallproportion of administrators per page.

Figure 4 shows that having a relatively high number of adminis-trators for a given content size is likely to reduce growth. There is astrong effect of the proportion of admins per page both on user andpage growth. For instance, while the last quantile of admins/pageratio enjoys near-zero growth rates over 8 months, the first quantiletops overall rates (!+50% for users, !+25% for pages). This ef-fect may be interpreted as the impact of strong governance activityon the proliferation of content and users.

6For this diagram, an increased level of detail called for a larger grid, here of 8 ! 7quantiles; U/P quantile means are represented by diagonal straight lines labelled “1–8”.

1 2 3 4 5

Quantile of

admins per good page1.0

1.1

1.2

1.3

1.4

1.5

1.6

Growth ratio

User growth

1 2 3 4 5

Quantile of


1.00

1.05

1.10

1.15

1.20

1.25

1.30

Growth ratio

Page growth

1.1

1.1

1.2

1.3

1.3

1.4

1 2 3 4 51

2

3

4

Quantiles of 'admins per good page'

Populationquantiles

User growth

1

1

1

1

1.1

1.1

1.1

1.1

1.2

1 2 3 4 51

2

3

4


Populationquantiles

Page growth

Figure 4: Growth landscape with respect to the proportion ofadmins per good page.

1 2 3 41.0

1.1

1.2

1.3

1.4

1.5

Population quantiles

Growthrate

User growth

1 2 3 41.00

1.05

1.10

1.15

1.20

1.25

1.30

1.35

1.40


Growthrate

Page growth

Figure 5: Growth landscape with respect to editing permission:red dashed refers to anonymously editable wikis, while bluesolid to wikis editable by registered users only.

1 2 3 4 5

Quantile of

edits per good page1.0

1.1

1.2

1.3

1.4

1.5

Growth ratio

User growth

1 2 3 4 5

Quantile of


1.05

1.10

1.15

1.20

1.25

Growth ratio

Page growth

1.2

1.2

1.2

1.3

1.3 1.4

1 2 3 4 51

2

3

4

Quantiles of 'edits per good page'

Populationquantiles

User growth

1.1

1.1

1.1

1.1

1.1

1.1

1 2 3 4 51

2

3

4


Populationquantiles

Page growth

Figure 6: Growth landscape with respect to the proportion ofedits per good page.

1 2 3 4 5

Quantile of

admins per user1.0

1.1

1.2

1.3

1.4

1.5

Growth ratio

User growth

1 2 3 4 5

Quantile of

admins per user1.00

1.05

1.10

1.15

1.20

1.25

Growth ratio

Page growth

1.2

1.2

1.3

1.3 1.4

1 2 3 4 51

2

3

4

Quantiles of 'admins per user'

Populationquantiles

User growth

1 11

1.1

1.1

1.1

1.1

1.1

1.1

1.1

1.1

1.2

1.2

1.2

1 2 3 4 51

2

3

4


Populationquantiles

Page growth

Figure 7: Growth landscape with respect to the proportion ofadmins per user.

We identified another significant effect when we considered edit-ing permission. As a binary variable, the editing permission vari-able generates only two groups of wikis (wikis that allow anony-mous editing versus wikis that restrict editing to registered usersonly). The growth landscape is consequently limited to a one-dimensional comparison over population quantiles. The results inFigure 5 show that for both dimensions—population and content—having no access control is likely to favor growth. While a strongerpage growth is quite unsurprising in wikis where no registrationis required, the fact that this factor also fuels user registration ismore puzzling. One might expect that if users can participate with-out the need of registration, few would be inclined to register. Ourresults suggest on the contrary that wikis with unrestricted registra-tion trigger participation more easily than wikis that restrict access.

3.3 Neutral indicatorsFinally, we consider two indicators that showed a markedly mildercorrelation with wiki dynamics.

On the one hand, we found that edit density (i.e. edits/page) cor-relates in a moderately negative way with user growth—with a rel-atively stronger effect depending on initial population size—whilethere is surprisingly no significant correlation with page growth(Figure 6).

On the other hand, higher administrator ratios (i.e. admins/user)have no significant effect on content or population growth, as evi-denced by the contour plot on Figure 7.



Growth regulators (2): admin density

able U/P , and initial wiki positions Ufirst and Pfirst altogether onthe same graph, yielding a phase diagram as plotted on Fig. 3.6 Inthis diagram, each dot (light color) corresponds to a wiki in thedatabase. Each arrow corresponds to a pair of quantiles “users perpage, population”. Widths and heights are proportional to user andcontent growth ratios, respectively. The size of the arrow representsthe strength of the observed growth in content and population forwikis in a given region of the wikisphere.

This graph should be regarded as a map of a portion of the wiki-sphere, showing the expected destiny of a wiki in terms of contentand population growth as a function of its initial position in thesame space. This diagram broadly suggests that a wiki’s positionis correlated with its subsequent fate. More precisely, it illustratesthat wikis in the upper/upper-right portion of the diagram are grow-ing faster, and more interestingly it provides an overview of demo-graphic dynamics in this region of the wikisphere.

3.2 Significant governance factorsTurning to governance features, we first analyzed the effects of theadministrator density on wiki dynamics by looking at the overallproportion of administrators per page.

Figure 4 shows that having a relatively high number of adminis-trators for a given content size is likely to reduce growth. There is astrong effect of the proportion of admins per page both on user andpage growth. For instance, while the last quantile of admins/pageratio enjoys near-zero growth rates over 8 months, the first quantiletops overall rates (!+50% for users, !+25% for pages). This ef-fect may be interpreted as the impact of strong governance activityon the proliferation of content and users.

6For this diagram, an increased level of detail called for a larger grid, here of 8 ! 7quantiles; U/P quantile means are represented by diagonal straight lines labelled “1–8”.

1 2 3 4 5

Quantile of


1.1

1.2

1.3

1.4

1.5

1.6

Growth ratio

User growth

1 2 3 4 5

Quantile of


1.00

1.05

1.10

1.15

1.20

1.25

1.30

Growth ratio

Page growth

1.1

1.1

1.2

1.3

1.3

1.4

1 2 3 4 51

2

3

4


Populationquantiles

User growth

1

1

1

1

1.1

1.1

1.1

1.1

1.2

1 2 3 4 51

2

3

4


Populationquantiles

Page growth

Figure 4: Growth landscape with respect to the proportion ofadmins per good page.

1 2 3 41.0

1.1

1.2

1.3

1.4

1.5


Growthrate

User growth

1 2 3 41.00

1.05

1.10

1.15

1.20

1.25

1.30

1.35

1.40


Growthrate

Page growth

Figure 5: Growth landscape with respect to editing permission:red dashed refers to anonymously editable wikis, while bluesolid to wikis editable by registered users only.

1 2 3 4 5

Quantile of


1.1

1.2

1.3

1.4

1.5

Growth ratio

User growth

1 2 3 4 5

Quantile of


1.05

1.10

1.15

1.20

1.25

Growth ratio

Page growth

1.2

1.2

1.2

1.3

1.3 1.4

1 2 3 4 51

2

3

4


Populationquantiles

User growth

1.1

1.1

1.1

1.1

1.1

1.1

1 2 3 4 51

2

3

4


Populationquantiles

Page growth

Figure 6: Growth landscape with respect to the proportion ofedits per good page.

1 2 3 4 5

Quantile of

admins per user1.0

1.1

1.2

1.3

1.4

1.5

Growth ratio

User growth

1 2 3 4 5

Quantile of

admins per user1.00

1.05

1.10

1.15

1.20

1.25

Growth ratio

Page growth

1.2

1.2

1.3

1.3 1.4

1 2 3 4 51

2

3

4


Populationquantiles

User growth

1 11

1.1

1.1

1.1

1.1

1.1

1.1

1.1

1.1

1.2

1.2

1.2

1 2 3 4 51

2

3

4


Populationquantiles

Page growth

Figure 7: Growth landscape with respect to the proportion ofadmins per user.

We identified another significant effect when we considered edit-ing permission. As a binary variable, the editing permission vari-able generates only two groups of wikis (wikis that allow anony-mous editing versus wikis that restrict editing to registered usersonly). The growth landscape is consequently limited to a one-dimensional comparison over population quantiles. The results inFigure 5 show that for both dimensions—population and content—having no access control is likely to favor growth. While a strongerpage growth is quite unsurprising in wikis where no registrationis required, the fact that this factor also fuels user registration ismore puzzling. One might expect that if users can participate with-out the need of registration, few would be inclined to register. Ourresults suggest on the contrary that wikis with unrestricted registra-tion trigger participation more easily than wikis that restrict access.

3.3 Neutral indicatorsFinally, we consider two indicators that showed a markedly mildercorrelation with wiki dynamics.

On the one hand, we found that edit density (i.e. edits/page) cor-relates in a moderately negative way with user growth—with a rel-atively stronger effect depending on initial population size—whilethere is surprisingly no significant correlation with page growth(Figure 6).

On the other hand, higher administrator ratios (i.e. admins/user)have no significant effect on content or population growth, as evi-denced by the contour plot on Figure 7.



Summary of results

Editsper user

Editionpermission

Adminsper user

Edits pergood page

Users pergood page

Admins pergood page

0.9

1.0

1.1

1.2

Page growth

Editsper user

Editionpermission

Adminsper user

Edits pergood page

Users pergood page

Admins pergood page

0.7

0.8

0.9

1.0

1.1

1.2

1.3

User growth



Summary of results

Variable Growth ratePopulation Content

STRUCTURAL

INDICATORS

User activity (E/U ) + + + +Edit density (E/P ) - —User density (U/P ) - - - -

GOVERNANCE

FACTORS

Editing permission (R) + + + +Admin ratio (A/U ) — —Admin density (A/P ) - - - -

Table 2: Effect of different factors on wiki growth rates.

3.4 Summary of findingsThe results of this study suggest that different structural and gover-nance-related factors have significant effects on the content andpopulation dynamics of a wiki. Table 2 and Figure 8 summarizethe correlations found between growth ratios and each of the vari-ables we considered, by comparing the gain in the population andcontent sizes between the last and the first quantile for each vari-able (variables in Figure 8 are ranked from the most positively tothe most negatively correlated).

If we focus on structural aspects of wikis, we note that the higherthe ratio of edits per user the faster the wiki grows, both in terms ofcontent and population. Wikis with very active user communitiesare not only likely to grow in content, but also to attract a largenumber of new contributors. This result contrasts with the oppositeeffect produced by high user density per page.

Edits

per user

Edition

permission

Admins

per user

Edits per

good page

Users per

good page

Admins per

good page

0.7

0.8

0.9

1.0

1.1

1.2

1.3

User growth

Edits

per user

Edition

permission

Admins

per user

Edits per

good page

Users per

good page

Admins per

good page

0.9

1.0

1.1

1.2

Page growth

Figure 8: Comparison of growth ratios between the last andfirst quantiles, for each variable considered.

As far as governance factors are concerned, we observed thesingular fact that population growth is in average more than 20%faster for anonymously editable wikis. This seems to support theintuition that less barriers favor population growth. Furthermorewe observed that, while too many administrators per page may hin-der the growth of a wiki (in terms of content size), the proportionof administrators per user does not appear to show a significant in-fluence on growth. In all the above cases, we observed a strikingcorrelation between content and population growth.

4. CONCLUDING REMARKSThe main outcome of this study is an account of the factors thatwiki communities should take into account in order to control theirdemographics. In this respect, we showed the remarkable dynam-ical intertwinement of population and content growth, which sug-gests that models of wiki dynamics will probably need to focus onthe strong interrelations between these two variables.

Representing via phase diagrams the impact of specific variableson wiki dynamics can be a valuable solution for wiki administra-tors for monitoring purposes and for social scientists as a first steptowards modeling. However, in order to develop accurate modelsof wiki dynamics, further empirical evidence is needed. To makethe data tractable for this study, we restricted the dataset in sev-eral ways. A more comprehensive study, beyond the scope of thepresent paper, should endeavor to investigate a larger spectrum ofwiki-based communities.

5. REFERENCES[1] U. Brandes and J. Lerner. Visual analysis of controversy in

user-generated encyclopedias. In Visual Analytics Scienceand Technology, 2007. VAST 2007. IEEE Symposium on,pages 179–186, 2007.

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Summary of results

structural indicators

I The higher the ratio of edits per user the faster the wiki grows.Wikis with very active user communities are more likely to attracta large number of new contributors.

I Opposite effect of high user density per page.

governance indicators

I Population growth is more than 20% faster for anonymouslyeditable wikis. Less barriers favor population growth.

I Too many administrators per page may hinder the contentgrowth of a wiki.

I The ratio of administrators per user does not show asignificant influence on growth dynamics.



Summary of results

structural indicators

I The higher the ratio of edits per user the faster the wiki grows.Wikis with very active user communities are more likely to attracta large number of new contributors.

I Opposite effect of high user density per page.

governance indicators

I Population growth is more than 20% faster for anonymouslyeditable wikis. Less barriers favor population growth.

I Too many administrators per page may hinder the contentgrowth of a wiki.

I The ratio of administrators per user does not show asignificant influence on growth dynamics.



Wiki viability: Beyond raw growth indicators

I Better metrics to assess the viability of a Web community

I content persistenceI vandalism detection timeI evolution of page/stub ratioI page creation rate

I Need of more fine-grained independent variables:

I rate, magnitude and temporal properties of disruptionsI ratio of lurkers per active usersI metacontent production indicators (talk pages, comments)I wiki structure (categories, namespaces)I social network indicators



Wiki viability: Beyond raw growth indicators

I Better metrics to assess the viability of a Web community

I content persistenceI vandalism detection timeI evolution of page/stub ratioI page creation rate

I Need of more fine-grained independent variables:

I rate, magnitude and temporal properties of disruptionsI ratio of lurkers per active usersI metacontent production indicators (talk pages, comments)I wiki structure (categories, namespaces)I social network indicators



Towards model-based predictions of wiki dynamics (1)

1. Collect large-scale data on wiki dynamics

2. Identify significant growth patterns

3. Build models of wiki dynamics and resilience againstdisruptions

4. Provide model-based predictions and governancerecommendations



Towards model-based predictions of wiki dynamics (2)

WikiTracer: Mapping the Wikisphere Measuring wiki viability D. Taraborelli


The end

Funding

I PATRES: Pattern Resilience (NEST-043268)

References

I Roth, C., Taraborelli, D., and Gilbert, N. (2008) Measuring wiki viability. Anempirical assessment of the social dynamics of a large sample of wikis.Proceedings of the 4th International Symposium on Wikis - WikiSym 2008, New York,NY, USA. ACM.

I Roth, C., Taraborelli, D., and Gilbert, N. (2008) Demographie des communautesen ligne: le cas des wikis. Reseaux (forthcoming)

I Roth, C. (2007). Viable wikis: Struggle for life in the wikisphere. Proceedings of the3rd international symposium on Wikis - WikiSym 2007, New York, NY, USA. ACM.


Documents

Measuring wiki viability - CRESScress.soc.surrey.ac.uk/web/sites/.../presentation/... · wikis belonging to the clean dataset. Measuring wiki viability D. Taraborelli. Viable wikisWiki