p.xiii Decisions permeate all human activity. We all make decisions, all the time, for
ourselves or for the organizations we work for. Sometimes we get them wrong and regret the consequences; and sometimes
we get them right but can't explain why. This is a textbook for courses to help students with such problems and generally
to improve their professional or private decision making, supported by tools of personal decision analysis.
p.38 A step beyond simply listing the pros and cons is for D [a person making a decision] to reason informally
about the three essential decision elements noted in Chapter 1, goals, options, and outcomes
p.59 Utility, as used here, is any numerical measure of welfare, satisfaction,
etc., such that [decision maker] D would prefer more [of that particular quantity, whatever it is] to less.
p.66 Decision analysis contributes to only part of the decision . It does not directly
address the critical task of identifying promising options.
p.132 Requirements of a Useful Decision Aid: Tool Essentials [section title]
To help [decision maker] D manage his/her private and professional life more rationally, [the] decision
aid needs to meet some essential requirements. The analytic strategy needs to assure that:
- The aid addresses the right question, whose answer, if sound, will help [decision maker] D decide.
- The aid makes use of all relevant knowledge available to [decision maker] D.
- Modeling is logically sound.
- The model input accurately represents the knowledge available.
- Output is in a usable, understandable, and timely form for [decision maker] D.
- The tool's cost is acceptable.
Unless all these requirements are met, the resulting "decision aid" is likely to be more harmful
than helpful to rational action.
p.139 A choice model can be structured in many different ways, appropriate in different circumstances...
Distinctions have to do with how useful the structure is for the decision at hand... Different structures can focus attention
on different aspects of the choice. This focus permits analytic effort to be spent where it can do the most good. An
excellent way to organize your thinking initially about what the key considerations are is with an influence sketch (shown
in Appendix 8A).[footnote: An influence sketch is a simple, qualitative version of the influence diagram, which
is a well-established computerized device, logically equivalent to a decision tree, that deals more compactly and clearly
with a complex representation of the problem, with many features of option outcome distinguished (Schacter, 1986)]
The influence sketch lays out the salient causal connections between option and utility in a way that permits
you to select a few to model explicitly.
p.151 An influence sketch helps identify contributors and settings that may have a significant
effect on the utility of options. The evaluation of options may involve considering numerous possibilities intervening
between commitment to an option and its ultimate utility to the decider. An influence sketch represents these graphically.
Essentially, influence sketches draw attention to critical developments, events, and subsequent choices which may
influence evaluation of the target choice and the interconnection between them. In particular, they show
what influences what, within the overall influence of target choice on objectives (see Figure 8A.1a).
More ambitious influence diagrams have been developed and used as computational
frameworks to evaluate options, much as decision trees do, but more compactly (Oliver and Smith, 1990).
