Validation results of the systems thinking network are displayed for each of the following trim levels: three, five, seven, and nine or more co-citations. The number of documents and the number of co-citations in each network are indicated. Internal consistency is reported as Spearman’s rank correlations of times cited by source documents to degree of co-citation. Community validity was tested using a χ2 test for independence between assigned network communities and subject communities. Stability was measured as the number of co-cited documents in the comprehensive network also found in the systems thinking network, and a Spearman’s rank correlation of the degree of co-citation for documents matched between the two networks.
| Systems thinking network trim levels | ||||
| ≥3 | ≥5 | ≥7 | ≥9 | |
| Network metrics | ||||
| Co-cited documents (number of nodes) | 246 | 71 | 35 | 19 |
| Co-citations (number of edges) | 1,292 | 271 | 105 | 44 |
| Internal consistency | ||||
| Spearman’s value (S) | 1,099,369 | 15,468 | 2151 | 584 |
| P value | <0.001 | <0.001 | <0.001 | 0.034 |
| ρ | 0.56 | 0.74 | 0.70 | 0.49 |
| Community validity | ||||
| X2 | 494.55 | 85.40 | 45.16 | 17.47 |
| Degrees of freedom (df) | 280 | 48 | 30 | 12 |
| P value | <0.001 | <0.001 | 0.037 | 0.13 |
| Stability to comprehensive network | ||||
| Number of matching documents | 68 | 36 | 24 | 18 |
| S | 26,613 | 4,459 | 1716 | 510 |
| P value | <0.001 | 0.0095 | 0.25 | 0.47 |
| ρ | 0.45 | 0.42 | 0.25 | 0.47 |