# Knowledge Sharing in Security-Sensitive Communities
## 3 Research Rationale
**H2:**: _Network density increases when homogeneity characterizes the participants of the discourse_  
The third hypothesis compares organizations that are sensitive to information security with those that are not. It distinguishes between homogeneous security-sensitive organizations and non-sensitive organizations. **H3:**: _Density increases when security sensitivity characterizes all the organizations participating in the discourse compared to the density in heterogeneous groups containing security-sensitive and non-sensitive organizations._  
Reciprocity and transitivity are two measures that refer to the structure of a network. The relationship between them is not always positive or negative. Hence, these two metrics should be studied separately [81]. We examine the metrics that reflect communication between participants: reciprocity, which refers to dual communication between two members in a directed graph [62], and transitivity, which is the degree of clustering, the tendency for triads of connections to appear in the network and therefore also refers to communication [63]. Reciprocity and trust are reflected in strong ties [65], and transitivity is expected to be high within networks with high trust [70]. Treating the communication level, which is expressed by reciprocity, average clustering, and transitivity, as the extent of message exchange, the fourth hypothesis is as follows:  
**H4:**: _Reciprocity, average clustering, and transitivity are higher for homogeneous security-sensitive organizations as compared to non-sensitive organizations._  
Radius and diameter are the minimum and maximum eccentricity observed among all nodes, respectively. Low radius and diameter imply higher connectivity [63] and effective information dissemination in the network [62]. Density, which refers to the proportion of links that exist in the graph and the maximum number of possible links in the graph, implies the level of connectivity in the network [62; 63] closer relationship between the members and high knowledge sharing among community members [80]. Hence, the next hypothesis concerns the effectiveness of knowledge sharing and examines the network structure as reflected by diameter, radius, and density. **H5:**: _Diameter and radius are smaller and density is higher in security-sensitive organizations as compared to non-sensitive organizations._  
Hypotheses 1-5 refer to the effect of the number of organizations, homogeneity, and sensitivity to information security on the network metrics, especially on density. Network metrics indicate the spread of knowledge and the level of communication [32; 33; 34; 35; 36; 82]. Since human behavior has a reciprocal effect on the network structure and vice versa, hypothesis 6 refers to the difference in network metrics between organizations that are sensitive to information and those that are not. **H6:**: _There is a difference in reciprocity, diameter, radius, and density, which reflect network structure, representing organizations that are sensitive to information, compared to network structures that represent organizations that are not sensitive to information._To summarize, Figure 1 incorporates all hypotheses and shows the relation between them in the research model, which reflects the overall knowledge sharing:  
Variables:  
Independent variables: (1) Number of organizations participating in the conversation; (2) Homogeneous in terms of sensitivity to information; (3) Type of organization: security-sensitive or not security-sensitive. Dependent variables: (1) Diameter; (2) Radius; (3) Density; (4) Reciprocity; (5) Avg. clustering; (6) Transitivity. Diameter, radius, and density reflect the effectiveness of knowledge spread. Reciprocity, average clustering, and transitivity reflect the level of communication.