ized rankings in Table 1. Based on symmetric ( reciprocated) citation patterns, CACM receives the high-est-degree centrality ranking, counting 46 ( 38.66%) of 119 journals as being in its immediate neighborhood. Using asymmetric (in-directed) citation patterns, which are a measure of prestige rather than simple centrality, CACM again receives the highest ranking, with citations from 101 ( 84.87%) of the 119 journals, 30 greater than its nearest competitor.

Bonacich Power (Beta = 0.06)

Rank Journal Raw Score 1 CACM 1193.010 2 DSS 972.685 3 EJOR 943.964 4 MS 922.228 5 IEEETSMC 848.698 6 IEEETKDE 833.462 7 I&M 817.880 8 IEEETSE 790.462 9 MISQ 714.948 10 IEEETEM 709.908 11 DSI 664.207 12 Omega 637.369 13 ACS 615.793 14 COR 602.174 15 IJHCS 584.977 16 ISR 584.595 17 AI 558.125 18 JMIS 553.574 19 IS 501.022 20 EJIS 492.562 21 IST 487.976 22 IEEETComp 475.624 23 JS&S 463.307 24 IEEETPDS 462.803 25 IEEEIS 440.927 --- ------- -------

A more insightful measure of degree prestige in a citation network is the Bonacich power index, which discriminates between citations received from more popular journals versus less popular journals (based on their respective degrees). The top 25 journals based on the Bonacich power index are shown in Table 2. There are several interesting differences between the Bonacich and Freeman degree results. Using the Freeman method, a large percentage of the top 25 journals have a management/professional orientation (including five of the top 10 journals). However, when using the Bonacich power method, many of these journals drop off the list, being replaced by more traditional IS journals.

Table 2. Most prestigious/ central journals in the IS

journal network.

This implies that while management/professional journals are prestigious within their immediate neighborhood, their prestige does not carry over to the network as a whole. The Bonacich measure, however, is quite sensitive to the selected attenuation factor (0.6, in this case).

CACM’s top ranking, using the Bonacich power index, indicates the journals ranked close to it likewise have a high degree of prestige. It is also instructive to examine the types of journals not citing CACM in 2003; for the most part, these are academic and practitioner journals from the management discipline.

While it is possible to calculate closeness and betweenness centrality measures in citation networks, information centrality is considered a more appropriate measure to use in such cases, since information exchange between journals does not always follow the

shortest path. Information centrality takes into account the actual strength of ties between actors, and thus indicates the relative drop in network efficiency brought about by removing a particular actor. Results for the top 25 journals appear in Table 2, and are highly correlated with the Freeman degree rankings. This makes sense, since in a citation network where the top journals tend to be widely cited, the removal of these journals will obviously cause a serious disruption to information flow. CACMis the most prominent journal in the network based on information centrality, once again highlighting its importance in dispers-

ing knowledge throughout the network.

Information Centrality

Rank Journal Normed Score 1 CACM 0.678 2 MS 0.646 3 MISQ 0.631 4 HBR 0.613 5 ASQ 0.597 6 IEEETComp 0.589 6 IEEESE 0.589 8 IEEEComp 0.578 9 AMR 0.574 10 OS 0.572 11 AMJ 0.567 12 IS 0.563 13 AI 0.562 14 ISR 0.558 15 JACM 0.557 16 I&M 0.556 17 SMR 0.554 18 IEEETSMC 0.549 19 EJOR 0.548 19 IEEETPAM 0.548 21 OR 0.539 22 IJHCS 0.532 23 IEEETKDE 0.531 24 JASIS 0.529 25 DSI 0.524 25 IEEESw 0.524

LIMITATIONS This study only examined citations made by network journals in a single year (2003). However, Spearman rank correlation tests indicate statistically significant correlations between the normalized rankings in our single-year study and several past multiyear ranking studies, increasing our confidence in the results. ³ It is possible that the age of cited journals could impact the results, since older journals have more published articles available to be cited. In addition, the journal classifications (IS, CS, Mgmt/Prof, and OR) used here, while based on prior studies, have unclear boundaries. However, one of SNA’s advantages is that it can in fact uncover subtle, unrecognized relationships between journals, and thus can aid in the development of more accurate classification schemes in the future.

FUTURE DIRECTIONS

The Internet has amplified the power of many existing networks and sustains a large collection of new networks (for example, the open source movement). Increasingly, there is recognition that network analy-

³A complete list of the 26 studies to which we compared our normalized rankings and the results of the corresponding correlation tests is available on request.