The Causal Loop Diagram (CLD) is a well-established technique for modelling cause-and-effect relationships between variable factors. There are many guides to using these node-and-link diagrams to make sense of complex systems. Some have noted that reading and creating the traditional CLD notation is not intuitive to everyone.
The following diagram is an extract of my Poverty Reduction Model in the classic Causal Loop Diagram notation, created with Kumu software. Most relationships are labelled with a plus sign, indicating that an increase in the first factor causes an increase in the second factor. The minus sign indicates the opposite, for example, the rule that earning more Employment Income decreases a Rent Subsidy. The large R indicates a reinforcing loop. The double crossbars indicate delays in two of the causal relationships.
Below is the same part of the Poverty Reduction Model, with my customized Kumu notation. The nodes are shapes, colour-coded by subject area. The relationship polarity is indicated by colour and line pattern, for greater visibility than the plus and minus signs. The loop has a descriptive name. Delays were not relevant in the project, so that notation was not used, thus simplifying the diagram. Social service professionals found it easy to understand this notation:
The Poverty Reduction Model is stored in Kumu’s database with additional custom fields. Any categorical field can be used to colour code the nodes or relationships. The circle sizes or line widths can be varied by any numerical field. Custom notations can be set up to instantly switch the diagram’s style. Thus, using Kumu, a causal loop diagram can be displayed in multiple formats for executive and technical audiences.
You can read more about variations on causal loop diagrams in sections 2.3.8 and 6.2.2 of my research report.