Wikipedia is one of the most popular sites on the Internet today. As its popularity increases, more and more students will be utilizing its articles as reference sources for academic work. This paper explores the emerging “wiki way” of Web 2.0 and highlights both the good and the bad of collaborative endeavors on the Internet. Metrics are posited for measuring the accuracy and completeness of Wikipedia articles based upon the number of people and the number of edits involved in each article. These metrics are evaluated using data from previous studies on Wikipedia metrics.
Wikipedia is a rapidly growing phenomenon in the online world of collaborative activities. Since the advent of the public Internet, many types of shared activities have been evolving, with massive multi-player online games leading the list of popular activities that have stood the test of Internet “time.” However, a new type of collaborative activity is gaining momentum, the wiki. As per Wikipedia, the online encyclopedia, a wiki is “a web application designed to allow multiple authors to add, remove and edit content” (Wikipedia, 2007b).
The origin of the word wiki has its roots in the Hawaiian language and is found to be derived from the phrase “awiwi, wikiwiki” which is translated to mean quick or fast (Hawaiian Dictionary, 2007). Ward Cunningham is widely attributed for pioneering the first wiki in 1995 by writing server software that allowed any web page to be edited by any user (Szybalski, 2005). The wiki works like a library for a document in that users check out the document, modify the document, then check it back in for other users to read and modify. Thus, a collected knowledge is contained within the document as well as archived through saving all previous editions.
College students of 2007 have grown up using web based resources and consider them to be a component of daily life (personal observation in the classroom of a 21st century college). As such, it is not surprising to see many reference lists stocked with web based articles, Internet sources and hyperlinks. However, is the Web the most authoritative source for academic work? Moreover, is Wikipedia an authoritative academic source given its dynamic nature? This paper explores these ideas and pushes the reader into the Wiki-World.
The Wiki Way
The wiki way is not a new concept; businesses have been trying to get the customer to aid in their workload since the advent of commerce. Many farms have “U-pick-em” areas and the buffet line is not a new concept. However, with the rise in popularity of the Internet and e-commerce, a new method of accomplishing the wiki way has emerged. Just think of the name, address and credit card information buyers fill out online for e-commerce sites. Imagine the number of airline requests that travelers type in for the airlines which include name, address, departure and destination airports, date of travel and seating preference. No, the wiki way is not new but the new uses that the Internet has enabled with its millions of users are astounding. Below is a short list of wiki applications currently on the Internet.
Wikipedia – customers building an “encyclopedia”
E-commerce – customers entering their own “data”
Second Life – customers building their “world”
RateMyProfessor.com – students adding content about faculty
digg.com – users rating articles to be read
MySpace.com – users post their own content
YouTube – users posting their own videos
Curriki.org – a place for faculty to exchange curriculum ideas
iReport – news viewers sending in news worthy stories, video and photos
These sites illustrate the growing popularity of Web 2.0 applications and the fact that users enjoy generating content for providers of web sites. Currently, the top ten list on Alexa.com (Alexa, 2007) reveals that four members are of the wiki variety, three members are of the search engine type and three entries are portal applications. Their names and rankings are given in the list below:
By far one of the most popular wikis (Alexa, 2007) Wikipedia has spawned many more projects as can be seen in Table 1 below:
of all Wikimedia
Directory of species
Wiki projects by the Wikimedia Foundation
Wikipedia has been constantly gaining in popularity and usage as is illustrated in Figure 1 below which gives the “reach” or percentage of Internet users (who have the Alexa toolbar) visiting the site:
The reach of Wikipedia
As can be seen from Figure 1, the reach of Wikipedia has been growing exponentially since its inception on January 15, 2001 (Wikipedia, 2007c). In addition to the astounding growth rate of users accessing the Wikipedia site, Wikipedia boasts over 1.8 million entries with approximately 609 million words, which is about 15 times the size of the Encyclopædia Britannica, the largest (print) English language encyclopedia (Wikipedia, 2007d). In addition, Wikipedia is growing internationally, boasting over 7.5 million articles in 250 languages (Wikipedia, 2007d).
In the academic realm, wikis are gaining popularity and usage in the classroom and libraries (Richardson, 2006; Stephens, 2006; Kamel-Boulos, Maramba & Wheeler, 2006), as well as in the research arena (Voss, 2006; Hill, Gaudiot, Hall, Marks, Prinetto, & Baglio, 2006). In light of this, these dynamic content sites will be appearing in literature and reference lists, forcing the academic community to address the soundness of the citation and of the site. This verification of the information will be a task for both students and faculty to tackle.
For all the good of Wikipedia and other wikis, there is a dark side to publicly accessible, democratically altered content. In a high profile case, a Nashville area resident changed the Wikipedia entry of John Seigenthaler, a one-time administrative assistant to Robert Kennedy, to read that Mr. Seigenthaler was involved in the Kennedy assassinations. The Nashville area resident claimed to have posted this to “fool” a colleague (Goodin, 2005; Said, 2005). While the article was corrected, the personal damage was done. This began the debate on policing Wikipedia (Wikienforcement with Wikienforcers?), rule changes for editing entries on Wikipedia and who is ultimately responsible and legally liable for content on a wiki space. (See Ken Meyers’ (2006) article for an informative legal treatment of the Seigenthaler case and applying the communications decency act to Wikipedia.)
Using Wikipedia as an Academic Reference
As Wikipedia grows and matures, it will be utilized as an academic reference in the 21st century learning environment, particularly by generations who are raised with it. As this occurs, new methods for citing and referencing Wikipedia entries will be required. In the future, the APA Publication Manual might contain reference list examples that look like:
where a time stamp that is more accurate than the day is added to “mark” the point in time when the article was accessed. Faculty will also have to incorporate Wikipedia use statements into their paper assignments, illustrating for the student appropriate use of Wikipedia articles. (For a discussion on syllabus narratives for Wikipedia see the list at: http://www.fibreculture.org/pipermail/list_fibreculture.org/2006-September/ ) As the public educational structure utilizes and embraces technology and Internet resources, more and more students will appear at their college classes ready to utilize these resources.
There have been many attempts to “measure” entries in Wikipedia for their value as authoritative academic sources. Korfiatis, Poulos and Bokos (2006) pose the metric of “article degree centrality” which is based on links to/from the article in question and has been used in social network analysis and search engine metrics. This quantitative metric “grades” an article in Wikipedia based upon the number of edges (a concept from graph theory, viewed as links in this construct) leading to or from an article. The maximum value of article degree centrality is 1 (one), and is based on the variability of the author(s) centrality indices (another graph theoretic notion which grades authors based on their relationships to other members and articles in the community). Utilizing a different approach, Stvilia, Twidale, Gasser and Smith (2005) introduce ten “information quality” problems that are qualitative in nature. These metrics are: accessibility, accuracy, authority, completeness, complexity, consistency, informativeness, relevance, verifiability and volatility. Many of these metrics deal with the language of the article and the culture of the contributor and are subjective by nature. Two of these metrics are addressed in the following sections and will be listed here, along with their defining characteristics, for reference purposes.
Difference between an encyclopedia article genre and the genre from which the text was imported
Information quality problems
(Stvilia, et al., 2005)
In addition to the metrics listed above, Wikipedia has received criticism due to the inherent untrustworthiness of a publication that can be edited by anyone which brings into question the scope and balance of the articles (Chesney, 2006). Chesney’s study revealed that experts (individuals reading articles in their field) rated the accuracy of Wikipedia’s information as high, but that 13 percent of the articles did contain errors.
Finally, the entry “Reliability of Wikipedia” found on Wikipedia’s site makes mention of collaborative editing by anyone and claims that reliability “requires also [sic] examining its ability to detect and rapidly remove false or misleading information” (Wikipedia, 2007e). This admission illustrates the editorial process and monitoring that is undergoing continuous change based on error discovery in the article building process. The vandalism to the John Seigenthaler article mentioned in the previous section is a perfect example of editorial problems that can occur with a collaboratively edited document and illustrates the need for editorial “change” in light of these problems. Wikipedia’s reliability is measured internally using the following set of criteria:
Accuracy of information provided within articles
Comprehensiveness, scope and coverage within articles and in the range of articles
Susceptibility to, and exclusion and removal of, false information
Susceptibility to editorial and systemic bias
Identification of reputable third-party sources as citations (Wikipedia, 2007e).
The criteria used by Wikipedia parallels the concerns of authors in this subject area and two points are constantly re-enforced throughout the literature: accuracy and completeness.
The definitions of accuracy and completeness, along with the hypotheses underlying these definitions, for using Wikipedia as an academic reference are given here:
Accuracy – The state of the reference material at the time of reference. It is assumed that as time passes, the accuracy of a Wikipedia reference diminishes due to edits and other modifications to the article. As a point of orientation, when using a Wikipedia article as a reference, it is 100 percent correct until the time at which an author (Wikizen) makes a change to the article.
Completeness – The coverage of a topic by a Wikipedia article. It is assumed that as time passes an article becomes more complete due to the editing and addition of material by multiple editors. It is further assumed that an article can never reach 100 percent completeness.
Accuracy and completeness are defined in a similar manner as previous authors in that accuracy measures change (Stvilia, et al., 2005) as well as information content (as viewed as a reference source) (Wikipedia, 2007e); and completeness measures multiple perspectives (Stvilia, 2005) and comprehensiveness (Wikipedia, 2007e). These definitions attempt to combine these ideas into one quantitative metric whose foundations rest on the collaborative nature of Wikipedia, the number of people editing an article and the number of edits performed on an article.
Accuracy and Completeness Metrics
It is assumed that a Wikipedia entry can never be 100 percent complete or accurate. Indeed, most definitions and encyclopedic entries leave something to be discovered, an alternative definition, or a usage omitted. Supporting this idea is Jimmy Wales, the co-founder of Wikipedia who said: “Wikipedia is a work in progress. Mistakes are made during the editing process. […] I think people have the wrong idea of how accurate traditional reference works are.” (Nasr, 2006). Further, Eric Schmidt, CEO of Google stated: “Google is not a truth machine and does not represent it to be so. We do the best we can. […] So I don’t think in our lifetimes we’ll ever get to a perfect answer.” (Bogatin, 2006).
These statements lead to the positing of accuracy and completeness metrics for Wikipedia entries. Define the following variables:
NP = Number of People Editing a Wikipedia entry
NE = Number of Edits to a Wikipedia entry
and criteria (with justifications) for a functional form for accuracy, A(NP, NE).
A(1,1) = 100 This criterion states that the Wikipedia article is 100 percent accurate upon its creation and use (initially) as a reference
These criteria illustrate that as more users make more edits the accuracy of the Wikipedia article as a reference decreases
These criteria illustrate that as the number of people making edits or the number of edits gets large, the value of the Wikipedia article as an academic reference gets small
a function which satisfies criteria i - iii and can describe the accuracy of a Wikipedia entry (for the purpose of an academic reference) is:
Equation (1) illustrates that as either the number of people editing the entry or the number of edits gets large, the accuracy of the entry, for the purposes of a historical academic source, decreases. This is due to the changing nature of the entries in Wikipedia and the dynamic nature of the wiki environment. The underlying variable, time, is always present in that as time elapses, more people contribute editorial content to Wikipedia entries thus changing the accuracy of the reference material. I.e. the longer a Wikipedia citation exists in a paper, the less accurate it becomes, provided edits are still being made to the article. It should be noted that NP and NE are measured from the time at which the article is cited as a reference in a paper.
The accuracy graph The completeness of a Wikipedia entry is increased as more people become involved. This is expressed in the completeness metric defined by equation (2). This equation satisfies similar criteria as the accuracy metric which are set forth here:
C(1, 1) = C0 This criterion states that when the Wikipedia article is first written, it has a completeness level of C0 (in this paper it is set to 45 percent)
These criteria illustrate that as more people contribute more edits to the Wikipedia article the completeness of the article increases
These criteria illustrate that as more people contribute more edits to the Wikipedia article the completeness will rise toward 100%
An equation that satisfies criteria iv – vi and also captures the exponential behavior of Wikipedia’s popularity (see Figure 1) is given here:
The initial assumption with the completeness metric is that an entry’s stub (a “stub” is an initial entry in Wikipedia that is in need of editing and material addition) is approximately 45 percent accurate. By the time that NP + NE = 20, the completeness is at 50 percent. I.e. after a combination of 20 people or edits have occurred, the article is 50 percent complete. As time elapses, the completeness of an article approaches 100 percent asymptotically as more edits are added to the article. In this instance, NP and NE are measured from the inception of the article. The behavior of this functional form (assuming NP = NE) is given in Figure 3 below:
The completeness graph Observing the functions C(NP,NE) and A(NP,NE) in the NP-NE – space, two behaviors are noticeable:
Completeness reaches the “completeness plateau” once many people have contributed content to the article, illustrating that the article is fairly a fairly complete description of the topic.
Accuracy reaches the “accuracy valley” after many people have performed many edits to the article, illustrating that the article has changed significantly and that its quality as an academic source is now in question.
These behaviors can be seen in Figure 4.
The completeness and accuracy graphs in NP-NE space
In using a Wikipedia article as an academic source, Figure 4 illustrates the problem encountered. The article needs to be complete, but it also has to be accurate. These behaviors are at opposite ends of the NP-NE space under consideration.
As a comparison with other metrics, data from Korfiatis et al. (2006) will be used to illustrate the difference between centrality (the Korfiatis et al. metric for authoritative sources which is based on graph theory – theory loosely associated with page ranking by search engines as well) and the completeness metric posed in this work. The data table from Korfiatis et al. is reproduced in Table 3 below, with the addition of the columns labeled C(NP,NE), and A(NP,NE). It will be assumed that NP = NEfor the construction of C(NP,NE) and A(NP,NE) due to the data set only containing NP. Physically this assumes that each contributor submitted one edit – a reasonable assumption.
(assume NP = NE)
(range 0 – 100)
(assume NP = NE)
Johann Wolfgang von Goethe
Centrality versus Completeness Table 3 illustrates that while the centrality metric is relatively low due to the low number of incoming and outgoing links to the articles the completeness is relatively high, reflecting that many people have contributed to the authoring of the article, making its content “complete.” Table 3 also shows that after an average of 262 edits by 262 people the accuracy metric is 3.71 on average, illustrating that the article has changed significantly since its stub was posted (NE = NP = 1). These behaviors are also exhibited in Figure 4.
Conclusions and Future Directions
Web 2.0 and dynamically altered content sites are here and are wildly popular. This brings about a change in how academic work can be researched and documented. This paper introduced the wiki way of Web 2.0 and illustrated the need for metrics to gage the accuracy and completeness of wiki content that is used for academic purposes. In addition, the pros and cons of wiki content were addressed and suggestions for metrics to gage the completeness and accuracy of wiki content for academic purposes presented. These metrics are a step in the right direction, but need to be refined and tested for validity in measuring wiki references and wiki citations. After all, it is a wiki world…now.
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