A consequence table is a summary matrix illustrating the performance of each alternative on each objective. It can take a variety of forms depending on the complexity of the problem and the depth of analysis that is possible with the resources available.
Simple Consequence Tables
In its simplest form, a consequence table may just use a simple rating (such as a rough and ready 5-star rating) to describe the performance of each alternative. In the example illustrated below, in each case, one star (*) represents the worst performing alternative one one objective (e.g. Alternative 1 is the most expensive), and 5 stars (*****) represents the best performing alternative one one objective (e.g. Alternative 1 offers the most incremental protection to a species at risk.)
* = Worst performing alternative and ***** = Best performing alternative (click to enlarge)
Simple consequence tables can be very useful at the scoping stages of any decision, or may be all that is required in simple or budget-challenged cases. In most cases, they can be developed on a flipchart in a single group session, and can provide many insights about all the other steps in the decision process (e.g. problems with problem definition, which objectives to use etc). Simple consequence tables may also be useful for describing the broad-brush outline of a decision problem to people unfamiliar with the issues.
There are obvious shortcomings with this level of analysis, however. Among these are:
- It provides no sense of how important the difference is between one star and five stars (e.g. what difference in actual protection is offered by “*****” relative to “*”?)
- Because they are sketched in, no rigor is applied in the assignation of the stars
- There is little scope to undertake a ‘trade-off analysis’ of people’s values based on these ratings (See step 5)
Because of these and other problems, a more quantitative consequence table is usually appropriate.
More Complex Consequence Tables
Below is an example of a consequence table developed to summarize some alternative power supply options to a remote community (click to enlarge):
Because real-world consequence tables can be more difficult to take in and understand, a handy trick is to use colour-coding techniques offered by programs such as Microsoft Excel to highlight the difference in performance across alternatives. In this example, “negatives” (e.g. cost) have been shaded with an appropriately-sized red bar and “positives” (e.g. jobs) have been shaded with an appropriately-sized red bar. (click to enlarge)
Note that in this example, objectives have not been organized hierarchically, though it is easy to see how they could have been. More complex decisions may have two or even three levels of objective hierarchy.
Evaluating alternatives is discussed further in Step 5.
- A consequence table is a succinct summary of the performance of diverse alternatives solutions to a decision, expressed in terms of evaluation criteria.
- Sometimes, a simple consequence table is appropriate to capture the ‘broad brush’ trade-offs that exist between alternatives
- Often, simple consequence tables need to be developed into more quantitative analyses in order to properly portray the trade-offs that exist between available alternatives