AHP (Analytical Hierarchy Process)
Tugas keempat gw mengenai AHP. Qta suru nyari apa siy AHP itu, step by stepnya, and benefitnya apaan ama contoh penggunaan AHP di Expert Choice. AHP adalah salah satu metode untuk mengambil keputusan, yang dikembangkan di Wharton School of Business oleh Thomas Saaty, yang memungkinkan si pembuat keputusan memodelkan sebuah problem yang kompleks dalam struktur yang hierarki (bertingkat-tingkat) yang menunjukkan hubungan antara goal, objectives (criteria), sub-objectives, dan alternatives. Lihat figure1
Step by Step in AHP:
1. Arranging the problem in a hierarchical fashion
2. Establish priorities
3. Each node is evaluated against each of its peers in relation to its parent node; these evaluations are called PAIRWISE COMPARISON
PAIRWISE COMPARISON are basic to the AHP methodology. When comparing a pair of “factors”, a ratio of relative importance, preference or likelihood of the factors can be established.
Three pairwise comparison modes:
§ Numerical judgments
are made using a nine-point scale, represent how many times one element is more important than another.
§ Graphical judgments
are made by adjusting the relative length of two bars until the relative lengths of the bars represent how many times more important one element is than the other.
§ Verbal judgments
are used to compare factors using the words Equal, Moderate, Strong, Very Strong, Extreme. Equal requires no explanation. Extreme means an order of magnitude – about 9 or 10 to 1. Judgments between these words, such as Moderate to Strong are also possible.
Once judgments have been entered for each part of the model, the information is synthesized to achieve an overall preference. The synthesis produces a report, which ranks the alternatives in relation to the overall goal. This report includes a detailed ranking showing how each alternative was evaluated with respect to each objective.
5. Sensivity Analysis
Sensitivity analyses can be performed to see how well the alternatives performed with respect to each of the objectives as well as how sensitive the alternatives are to changes in the importance of the objectives.
Benefit of AHP:
In summary, AHP makes it possible for executives to assimilate all the facts, weigh the pluses and minuses, reach, re-evaluate, and communicate their decision. Once an initial decision is made, it is not final; even a strong willed decision maker is subject to external pressures from special interest groups such as, suppliers, customers, employees, trade unions or politicians. Objectives that were thought to be central to a decision, may, under these outside influences, become less central or dominant and a re-evaluation becomes necessary. Gradually, priorities are changed until a new, re-shaped, decision emerges. Without a decision model audit-trails are lost and executives find it impossible to systematically review or retrace the steps and sub-decisions made in the decision process. The difficulty of conducting a proper review increases exponentially with the number of objectives.