Systems Thinking has concept of Hard and Soft Systems as previously covered.
Hard Systems traditional approach from 1930s.
Soft Systems formalised by Peter Checkland in 1970s.
Examples of Hard Systems approaches:
- traditional MS/OR
- RAND (developed around 1955)
- systems engineering
- system dynamics (developed 1956)
Approaches based on following assumptions:
- Clearly defined problem
- Decision makers objectives are known as well as measurable criteria to know when objectives met
- Alternative courses of action specified:
- list of options, or
- decision variable sets with known constraints on decision choices
- in addition to one of the above, all required input data is available
- Relatively well structured problem – resolvable relationships between variables expressible in quantitative form
- Effort to determine optimal solution is feasible
- Problem sufficiently well insulated from wider system of interest
- Problem of technical nature, largely devoid of human aspects and implementation of solution can be enforced
Hard Systems defined as systems which have:
- Something tangible (computer system)
- Something that solves specific problems
- Something measurable by metrics
- Reductionist in nature
- Scientific/logical approach to problem solving
Traditionally SSADM approach used in development of software projects, computer systems and data processing systems:
- Problem identified
- Broken down into functional parts
- Structured approach taken to design, build and implement
Hard Systems use defined methodologies to provide well-defined solutions to stated problems.
Key point is having tightly defined goals/objectives measured by tangible metrics.
Example: stock control system – metrics relating to level of stock and turnover of stock.
Focus of Hard Systems – quantitative approach – systematic approach with sum of parts equal to the whole.
Hard Systems have predictable behaviour. Approach is black and white.