BUSINESS PERFORMANCE MANAGEMENT Analytical Hierarchy Process (AHP): A Multi-Objective Decision Making Technique Jason C.H. Chen, Ph.D. Professor of MIS School of Business Gonzaga University Spokane, WA 99258 chen@jepson.gonzaga.edu Dr. Chen – Business Intelligence AHP - 1 Analytical Hierarchy Process • In many situations one may not be able to assign weights to the different decision factors. Therefore one must rely on a technique that will allow the estimation of the weights. • What is a solution? • One such process, The Analytical Hierarchy Process (AHP), involves pairwise comparisons between the various factors. Dr. Chen – Business Intelligence AHP - 2 Analytical Hierarchy Process (cont.) • The process is started by the decision maker creating the value tree associated with the problem. • Then proceed by carrying out pairwise comparisons, both between – Alternatives on each factor, and – Factors at a given node. Dr. Chen – Business Intelligence AHP - 3 Application Case of AHP • Jane is about to graduate from college and is trying to determine which job offer to accept. She plans to choose between three offers by determining how well each offer meets the following criteria (objectives): – – – – High starting salary Quality of life in city where job is located Interest of work Nearness of job to family Dr. Chen – Business Intelligence AHP - 4 Assumptions • Jane has hard time in prioritizing those criteria. In other words, she needs to find one way to decide the weights for those criteria. AHP provides such a function. Dr. Chen – Business Intelligence AHP - 5 Determine the problem • What job offer will give Jane possibly highest satisfaction? • Structure the hierarchy by putting the top objective (satisfaction with job), criteria, and alternatives as follows. Dr. Chen – Business Intelligence AHP - 6 Structure of the Problem Satisfaction with a Job criteria; n=4 Starting Salary Job A Dr. Chen – Business Intelligence Life Quality Job B Interest Nearness to Family Job C AHP - 7 Structure of the Problem Satisfaction with a Job criteria; n=4 Starting Salary Job A Life Quality Job B Web site: http://www.hipre.hut.fi/ Dr. Chen – Business Intelligence Interest Nearness to Family Job C AHP - 8 The Principle of the AHP … • The principle of the AHP relies on the pairwise comparison. This comparison is carried out using a scale from 1 to 9 as follows: – – – – – – – – – 1 Equally preferred 2 Equally to Moderately preferred 3 Moderately preferred 4 Moderately to Strongly preferred 5 Strongly preferred 6 Strongly to Very Strongly preferred 7 Very Strongly preferred 8 Very to Extremely Strongly preferred 9 Extremely preferred Dr. Chen – Business Intelligence AHP - 9 A pairwise comparison matrix for the criteria level Satisfaction with a Job Salary Quality Interest Nearness Salary 1 5 2 4 Quality 1/5 1 1/ 2 1/ 2 Interest 1/ 2 2 1 2 Nearness 1/ 4 2 1/ 2 1 We assume that “Starting Salary” is strongly more important than “Life Quality”. That is why 5 is entered into the Salary row and Quality column. Compared to Interest, Salary is just a little bit more important. That is why 2 is entered into Salary row and Quality column. Similarly, Salary is moderately to strongly preferred than “Nearness”. That is why 4 is entered into the Salary row and Nearness column. Dr. Chen – Business Intelligence AHP - 10 A pairwise comparison matrix for the criteria level Satisfaction with a Job Salary Quality Interest Nearness Salary 1 5 2 4 Quality 1/5 1 1/ 2 1/ 2 Interest 1/ 2 2 1 2 Nearness 1/ 4 2 1/ 2 1 Web site: http://www.hipre.hut.fi/ Dr. Chen – Business Intelligence Since n=4, there are 6 [n*(n-1)/2] judgments required to develop each matrix. Why? AHP - 11 Using the same steps of 3 and 4 (see handout) to determine the score of each alternative on each criterion. Take the first criterion “Salary” as an example. One pairwise matrix is constructed as follows (details see step 4 on the handout): In terms of criterion of “Salary”, Job A is moderately important (“2”) than Job B. However, Job A is essentially more important (“4”) than Job C. SALARY A1 Job A Job B Job C Job A 1 2 4 Job B 1/ 2 1 2 Job C 1/ 4 1/ 2 1 Dr. Chen – Business Intelligence AHP - 12 The next two pairwise matrices (for “Life Quality” and “Interest”) are as follows (see step#6 on the handout): Quality A2 A3 Job A Job B Job C Job A 1 1/ 2 1/3 Job B 2 1 1/3 Job C 3 3 1 Interest Job A Job B Job C Job A 1 1/ 7 1/ 3 Job B 7 1 3 Job C 3 1/ 3 1 Dr. Chen – Business Intelligence AHP - 13 The last pairwise matrix (for “Nearness to family”) is listed below: A4 Dr. Chen – Business Intelligence Nearness Job A Job B Job C Job A 1 1/ 4 1/ 7 Job B 4 1 1/ 2 Job C 7 2 1 AHP - 14 How to verify that the data entered in the comparison matrices is acceptable Consistency Index (C.I) is computed as follows (see handout, p.5) C .I . max n n 1 4 . 0477 4 0 . 0159 3 We then compare the value of C.I. to the value of random index (R.I). If the ratio of C.I. to R.I. is less than 10%, then we can say the judgment process is relatively consistent and the matrix is acceptable. Otherwise, the decision maker may need to re-examine the judgment process and re-compare criteria or alternatives. The consistency ratio (C.R.) is computed as follows: C.R. = C.I. / R.I. = 0.0159/0.9 = 0.0176666 = 1.7% < 10% Random Indices (R.I.) for Consistency Check n R.I. 2 0 3 .58 Dr. Chen – Business Intelligence 4 .90 5 1.12 6 1.24 7 1.32 8 1.41 9 1.45 10 1.51 AHP - 15 Satisfaction with a Job Quality Interest Nearness Salary 1 5 2 4 Quality 1/5 1 1/ 2 1/ 2 Interest 1/ 2 2 1 2 Nearness 1/ 4 2 1/ 2 1 SALARY A1 Salary Job A Job B Job C Job A 1 2 4 Job B 1/ 2 1 2 Job C 1/ 4 1/ 2 1 A3 Interest Job A Job B Job C Job A 1 1/ 7 1/ 3 Job B 7 1 3 Job C 3 1/ 3 1 Dr. Chen – Business Intelligence A2 A4 Quality Job A Job B Job C Job A 1 1/ 2 1/3 Job B 2 1 1/3 Job C 3 3 1 Nearness Job A Job B Job C Job A 1 1/ 4 1/ 7 Job B 4 1 1/ 2 Job C 7 2 1 AHP - 16 We will open an existing model http://www.hipre.hut.fi or http://hipre.aalto.fi/ File name: mbus673.jmd Dr. Chen – Business Intelligence AHP - 17 Display the “weights” entered in the “Goal” or “Criteria” 1) Double click or 2) Select an “Element” then click Priorities then AHP Double click double click Dr. Chen – Business Intelligence AHP - 18 (p.4 of Handout) Dr. Chen – Business Intelligence AHP - 19 Result from “Analysis of Composite Priorities … “ click According to the BAR chart, AHP suggests that Jane should take Job B Dr. Chen – Business Intelligence AHP - 20 Result from “Analysis of Composite Priorities … “ – with Values According to the “Values”, AHP suggests that Jane should take Job B (you need to “Add total” , see the next slide) Dr. Chen – Business Intelligence AHP - 21 Result as Text Value Tree 0 satisfaction with a job 1 salary 0.512 0 . 5714 2 job A 0.571 S 1 0 . 2857 2 job B 0.286 0 . 1429 2 job C 0.143 1 life quality 0.098 0 . 1633 2 job A 0.163 S 2 0 . 5409 2 job B 0.540 2 job C 0.297 0 . 2971 1 interest 0.244 0 . 0882 2 job A 0.088 S 3 0 . 6687 2 job B 0.669 0 . 2431 2 job C 0.243 1 nearness to family 0.146 2 job A 0.082 0 . 0824 2 job B 0.315 S 4 0 . 3151 2 job C 0.603 0 . 6025 Composite Priorities job A salary 0.293 life quali 0.016 interest 0.021 nearness t 0.012 Overall 0.342 Dr. Chen – Business Intelligence job B 0.146 0.053 0.163 0.046 0.408 step 7 (p.5) job C 0.073 0.029 0.059 0.088 0.249 AHP - 22 Save your work again click Dr. Chen – Business Intelligence AHP - 23