The co-citation network derived from this first sub-period consists of 20 authors. As visualized in Figure 1, four communities (clusters) are identified in the map.
A first cluster composed by 6 red nodes is labelled as (1) Knowledge-based theory (K-based theory) since its authors are representatives of this topic (e.g. Nelson, RR; Nonaka, I; Spender, JC). The green cluster (6 authors) is named (2) Knowledge-based systems (K-based systems) as the clustered authors have provided relevant contributions in this area, including Skuce, D; Boose, J; and Gaines, BR. The blue cluster of five authors is labelled (3) Technology-based strategy, as it groups some economists whose contributions are referred to the development of technology focused on social, cognitive and behavioural aspects of individuals in organisations, including Simon, HA; Von Hippel, E; Kogut, B; Clark, KB; and Sanchez, R. Finally, the fourth cluster, in yellow, contains three authors oriented to the research on (4) Decision support systems (DSS).
Figure 1. Co-citation map of authors, 1986-1996.Note. Colors indicate different clusters and node size indicates citation weights. |
The co-citation map of the second sub-period was built with 39 authors grouped in four clusters (see Figure 2) as well. We provide a consecutive numbering of clustering. The fifth cluster, located in the red zone, is labelled (5) Strategic management given that important strategists are present in that cluster. This is the largest cluster in the network containing 11 authors focused on topics like competitive advantage, strategic management, corporate strategy, innovation, organisational capability, and some others (e.g. Grant, RM; Teece, DJ; Kogut, B; Spender, JC; Cohen, WM). The green cluster, of 10 authors, is named (6) K-based theory, a cluster that was also identified during the first sub-period. The two most cited authors in this cluster are devoted to knowledge theories, like Nonaka, I (1128 citations in the network), who introduced notions on knowledge creation, and Polanyi, M (320 citations in the network), who firstly emphasized the study of tacit knowledge. The remaining authors in cluster 6 are related to a wide range of innovation-related topics including knowledge management, technology strategy, new product and process design, and organisational change, among others (e.g. Leonard-Barton, D; Brown, JS; Hansen, MT; Wenger, EC; Orlikowski, WJ).
Figure 2. Co-citation map of authors, 1997-2006.Note. Colors indicate different clusters and node size indicates citation weights. |
The blue cluster, consisting of nine authors, represent the topic of (7) Organisational learning and behaviour. Some of the researchers highlighted in this cluster are Senge, PM; Argyris, C; Weick, KE; Eisenhardt, KM; Argote, L; and Walsh, JP. Finally, we labelled the yellow cluster of nine authors as (8) KM foundations, since some foundational contributors and developers of KM-specific notions are present including Davenport, TH; Wiig, KM; Alavi, M; and Zack, MH.
According to citation weights, the top five important figures of KM during this second sub-period are Nonaka, I (1,128 citations); Davenport, TH (714 citations); Polanyi, M (320 citations); Grant, RM (298 citations); and Leonard-Barton, D (275 citations).
152 authors were mapped in the co-citation network of the third sub-period, forming 7 communities (Figure 3). The red cluster, of 41 authors, is labelled as (9) Strategic management. Distinguished researchers devoted to strategic topics are contained in cluster 9, including Grant, RM; Teece, DJ; Barney, JB; Eisenhardt, KM; and Porter, ME. Likewise, we detect several organisational theorists (e.g. March, JG; Chesbrough, HW; Hitt, MA; Edlund, G; Powell, WW), as well as some scholars of innovation in organisations (e.g. Cohen, WM; Gupta, AK; Von Hippel, E; Chesbrough, HW; Tushman, ML; Dougherty, D). (10) Marketing strategy is the tenth cluster located in the green area, a cluster not visualized previously. The following authors have a strong orientation to marketing topics: Hair, JFJ; Bagozzi, RP; Anderson, JC; Darroch, J; and Hult, GTM. We note that in this cluster 10 there are a couple of authors oriented as much to psychological issues as to the study of consumers (e.g. Fornell, C; Nunnally, JC; Bagozzi, RP; Anderson, JC; Baron, RM).
The eleventh cluster is a standing topic, (11) KM foundations, located in the blue zone of the map. Out of the 23 authors, Nonaka, I; Davenport, TH; Drucker, PF; Zack, MH; Wiig, KM, among others are the most crucial names. In this cluster, we also find figures related to research about intellectual capital like Bontis, N; Edvinsson, L; and Stewart, TA. The yellow cluster with 22 authors represents the topic of (12) KM systems and technology. In this cluster, the following authors are clustered: Alavi, M; Bock, GW; Wasko, MM; Kankanhalli, A; Markus, ML; Venkatesh, V; Hofstede, G; Jarvenpaa, SL.
Authors oriented to the study and applications of theories within the organisational framework are grouped in the thirteenth cluster (purple area). Some of these theories (e.g. knowledge-based theories, social learning theories, critical theories, and many other sociological and organisational theories) are typified by authors like Wenger, EC; Polanyi, M; Tsoukas, H; Spender, JC; Yin, RK; Alvesson, M; Blackler, F. For that reason, we label this community as (13) Organisational theories. The blue light area of 12 nodes is represented by the topic of (14) Networks and knowledge transfer. Here we observe some authors oriented to the study of social networks, collaboration and knowledge transfer within the organisational realm as well (e.g. Hansen, MT; Argote, L; Szulanski, G; Nahapiet, J; Burt, RS; Granovetter, MS; Cross, RL). The last cluster in the network was also identified in the second period, (15) Organisational learning and behaviour. It is located in the blue light zone totalling nine authors (e.g. Pfeffer, J; Walsh, JP; Daft, RL; Crossan, MM; Senge, PM; Argyris, C).
We also detect the permanence of clusters referred to themes like strategy, innovation, organisation, organisational learning, organisational behaviour, and KM foundations. Nevertheless, the KM systems and technology community is more emphasized now, while the focus on marketing strategy emerges. Appendix 1 displays summarized information derived from clustering by sub-periods.
Figure 3. Co-citation map of authors, 2007-2015.Note. Colors indicate different clusters and node size indicates citation weights. |
Table 1 shows statistical information obtained from each network. The increasing number of nodes and edges between nodes indicates a field of strong development. The average degree of nodes in networks represents the level of importance that authors have been reaching over the time; regardless of the dynamics of citation as time goes by (
McCain, 1990). Appendix 2 displays the ten most important authors by sub-periods in terms of citation weights, highlighting the influence of experts coming from the economics, business, management, and computer science arenas over the whole period here examined.
Table 1 Statistical description of the KM network. |
Network measures | 1986-1996 | 1997-2006 | 2007-2015 |
Nodes | 20 | 39 | 152 |
Edges | 79 | 741 | 11,186 |
Average degree | 4 | 19 | 74 |
Diameter | 3 | 1 | 2 |
Density | 0.2 | 0.5 | 0.5 |
Average clustering coefficient | 0.5 | 0.5 | 0.5 |
The values of network diameter, density and average clustering coefficient indicate how compact the co-citation networks are, showing a considerable homogeneity of the KM field. Using the network shrinking operation provided by Pajek, we visualize how co-cited communities connect to each other (see figures 4a, b, c). In sub-period 1986-1996, clusters (1) K-based theory and (3) Technology-based strategy are the most important in the network, according to node size (see Figure 4a), and are the most connected ones in the network. At the same time, (2) K-based systems is a cluster with zero connections and low representativeness. However, top co-cited authors according to link strength (ls) measures are present in this cluster 2, highlighting Skuce, D and Boose, J (ls: 76), Skuce, D and Motta, E (ls: 52), Skuce, D and Lethbridge, TC (ls: 44), Skuce, D and Meyer, I (ls: 44), and finally Skuce, D and Gaines, BR (ls: 44).
Figure 4. Relations among KM communities using network-shrinking operation in Pajek; (a): 1986-1996, (b): 1997-2006; and (c): 2007-2015. |
In sub-period 1997-2006, communities are even more connected, despite the introduction of new groups of authors less oriented to systems and technology, as previously observed. We note that major relatedness of communities is given between clusters (5) Strategic management and (6) K-based theory (see Figure 4b). This connection among strategists and knowledge theorists was a pattern already visualized in 1986-1996. Most co-citation relations are commonly established with the foundational author Nonaka, I, as for example: Nonaka, I and Davenport, TH (ls: 797), Nonaka, I and Polanyi, M (ls: 531); Nonaka, I and Grant, RM (ls: 451); Nonaka, I and Leonard-Barton, D (ls: 440); and Nonaka, I and Brown, JS (ls: 332).
During the final sub-period (2001-2015), the relatedness between clusters (9) Strategic management and (11) KM foundations stand out (see Figure 4c). Here, we notice a common trend as observed from sub-period 1-3, since strategic communities and foundational KM thinkers are more strongly linked. Likewise, major citation linkages are produced with Nonaka, I as for instance: Nonaka, I and Davenport, TH (ls: 1543); Nonaka, I and Grant, RM (ls: 1353); Nonaka, I and Polanyi, M (ls: 1045); Nonaka, I and Alavi, M (ls: 948); Nonaka, I and Teece, DJ (ls: 817). Only one isolated cluster was formed during the period covered by our research, namely during sub-period 1 (cluster 2).