Important concept and practise. Repeat analysis process several times to identify/enhance facts, data and understanding. Iteration, along with different views, helps produce robust analysis.

Decision Trees

Identifies options available and key choices. Analysis of complex decisions with significant uncertainty can be confusing because: the consequence that will result from selecting any specified decision alternative cannot be predicted with certainty. there are often large number of different factors that must be taken into account may be useful to consider possibility of reducing uncertainty in the decision by […]

Cause and Effect Diagram

Cause and Effect diagrams sometimes called fishbone diagrams or Ishikawa (name of the developer). Models casual relationships that occur. Identifies what is causing what effect. Will identify multiple causes if they exist – critical for understanding complex situation. Will also identify feedback loops. Diagram focuses on causes rather than effect. Start with definition of problem and then ask why is […]

Further Model Types and their uses

Rich Pictures Often first stage in design process Free format diagram to capture system Identifies politics, processes, emotions Theme places in middle, link words placed around it Systems Dynamics Show states and rates for given situation Example: human population and rate of increase/decrease Other states can be modelled against human population such as food consumption, food production, water consumption Allows […]

A brief summary of Model Considerations

Number of elements to consider when building models: Define model purpose when designing model. Model should be verified and validated. Designed by humans from specific perspective, may be flawed. Model only gives partial view of situation/system. Number of models required to gain full understanding of situation/system providing different views. Abstraction level required is key decision.

Other Classification Systems

In addition to static and dynamic, models can also be defined as quantitative and qualitative. Quantitative models similar to numeric models quantify situation¬†with facts and data Qualitative models shows structure of elements/components Other model classifications are hard and soft models. Hard models are like quantitative models and are based on facts and data. Soft models are like qualitative models and […]

Static or Dynamic Models

Models classified as either static or dynamic models. Static models tend not to change much, only if significant change in situation London tube map changes only when new line added powerful source of information/understanding if situation is constant Used in business environment to understand enterprise/system, simulation used to analyse behaviour of system. Most models are static, simulation is necessary for […]

Word, Visual and Mathematical Models

Word Models: Consist of words. Examples: a specification, an abstract Provide significant amount of information Can be structured in different ways Weakness: linear and not multi-dimensional – hard to provide complex relationships, can become unwieldy Visual Models: Type of picture – ‘a picture paints a thousand words’ Show a lot of information in small amount of space Show relationships between […]