Click for next page ( 80

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement

Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 79
Tier 2--Weighted-Matrix Delivery Decision Approach 79 Table 5-1. Weighted ranking of selection factors for the example project. Weight Selection Factor 50 Project complete by November 1, 20XX. 25 Cost not to exceed $200 million. 15 Minimize impact on operations and passengers. 10 Minimize staffing requirements during design and construction. 100 Total The result of Step 2 will be a weighted ranking of up to seven selection factors. A maximum of seven is selected because research has found that when there are more than seven variables it becomes difficult for people to make distinctions among them (Miller 1956). The weightings should total 100 points. Equal factor weightings are not recommended because distinguishing the level of importance of each factor (goals and critical issues) is necessary for the decision process. Additionally, no single factor should have a point value of less than five because a point value that low will not have a sufficiently significant influence on the final decision and may in fact make the selection more difficult. The next steps (Steps 3, 4, and 5) involve combining the weighted rankings with a scoring of the project delivery methods to arrive at a final selection of the most appropriate delivery method. Delivery Selection for the Example Project--Step 2. Table 5-1 shows how weighted rank- ing worked in the example project. In Table 5-1, selection factors for the example project have been weighted to reflect their influence on the success of the example project's delivery. These weightings are project dependent and should be agreed upon by key airport team members. Step 3. Score Project Delivery Methods The third step involves a scoring of the alternative delivery methods that survived the screen- ing process of Tier 1 analysis. Each of these delivery methods will have a bearing or influence on the selection factors, which stem from the project goals and pertinent issues. The key decision- makers must translate this influence into a score to arrive at a decision. To achieve the total scores for each delivery method, airports should do the following: Using the scale provided in Table 5-2, assign a score to each delivery method that represents its influence or bearing on each selection factor. Score all delivery methods for each factor before moving to the next factor. Repeat the previous step for each selection factor. When all of the delivery methods have been scored, multiply each delivery method's factor weight by its score to achieve a weighted score for each delivery method. Sum all of the weighted scores to arrive at a total score for each delivery method. Table 5-2 provides a scale for scoring each delivery method's bearing on each selection factor. The scores range from 1 to 10 so that when they are multiplied by the factor weight, the total score will range from 0 to 1,000. The scores are subjective, so a detailed definition for each numerical score is provided adjacent to the score in Table 5-2. When scoring the delivery methods, airports should discuss the advantages and disadvantages of each delivery method (see Chapter 3 and Step 4 of the Tier 1 approach). The alignment of these advantages and disadvantages with the selec- tion factors forms the basis for the scoring. In assigning the scores, the airport should work in a

OCR for page 79
80 A Guidebook for Selecting Airport Capital Project Delivery Methods Table 5-2. Project delivery scoring scale. Score Definition 10 The evidence that the delivery method positively aligns with the project objective or issue is of the highest possible order of affirmation. 8 The delivery method strongly aligns with the objective or issue and is demonstrated in practice. There is a slight risk that the objective or issue may not be beneficial. 6 Experience and judgment point to the delivery method strongly aligning with the objective or issue. There is a mild risk that the objective may not be beneficial. 4 Experience and judgment slightly point to the delivery method aligning with the objective or issue. There is a strong risk that the objective will be negatively affected. 2 There is little benefit to applying the delivery method for this goal or objective. There is a strong likelihood that the object will not be achieved. 9,7,5,3,1 Intermediate values between two adjacent judgments. (Adapted from Saaty 1990.) team to come to a decision by consensus. The rationale for each individual score should also be carefully documented. Consideration should also be given to the relative scores for each delivery method to ensure consistency. Similar to the development of factor weights, the scoring can be done simply through a group discussion among key airport team decision makers. Table 5-3 provides a weighted-matrix template. The matrix shown contains three delivery meth- ods. However, a larger or smaller number of delivery methods can be analyzed, depending upon the results of Tier 1. For example, two types of DB delivery methods with various procurement Table 5-3. Weighted-matrix template. Project Delivery Method DB Specify DBB CMR Procurement (______________)* Selection Factor Weighted Weighted Weighted Score Score Score Factor Weight Score Score Score Factor 1 (e.g., Project Goals) Factor 2 (e.g., Airport experience) Factor 3 (e.g., Market issues) Factors 4 to 7 ... Total Score *Refer to the section titled "Definition of Delivery Methods" in Chapter 2 for procurement options. The DB procurement options considered in Tier 2 are primarily Best-Value Procurement with Fixed Price and DB Qualifications-Based Procurement with Negotiated Price. DB Low Bid is an option, but it is not recommended in this guidebook for the majority of DB projects.

OCR for page 79
Tier 2--Weighted-Matrix Delivery Decision Approach 81 methods could be competing in this matrix. The matrix can also contain up to seven selection fac- tors for each project. The result of Step 3 will be a scored ranking of the delivery methods in question. The delivery method with the highest total score will be the most appropriate method for the given project. The next steps involve documenting the individual scores, making a decision, and creating a Project Delivery Selection Report. Delivery Selection for the Example Project--Step 3. Table 5-4 shows how an airport might score the project delivery methods for the example project. Note that only the CMR and DB project delivery methods made it through the Tier 1 filter for further consideration in Tier 2. Also note that the scores in the example below are project dependent and will certainly change from project to project. Explanations of the scores for the project delivery methods for the example project are the following: Project completion factor. The project completion factor relates to a project goal. In this case, the project has a fixed end date of November 1, 20XX. The airport believes that the completion date can be achieved with CMR delivery. The airport also believes that CMR will require the use of multiple bid packages to achieve the schedule, which adds a risk for meeting the schedule date, so CMR = 6 (in this case). DB delivery provides for a single entity to coordinate design and con- struction. DB also allows for an airport to specify a fixed end date in the procurement documents and the contract. According to what has been demonstrated in practice, the airport is confident that the end date can be achieved through a DB delivery, so DB = 8 (in this case). Cost containment factor. The cost containment factor relates to a project goal. The project has a maximum budget of $200 million. DB delivery has demonstrated in practice that a fixed price can be negotiated early in the project development process. It has also been demonstrated that DB provides the lowest average cost growth of the two methods in question, so DB = 8 (in this case). CMR also provides the ability to meet a fixed price, but the airport is not as confident that it will be able to negotiate a fixed price as early in the process as it can with DB, so CMR = 6 (in this case). Impact on passengers and operations factor. This factor stems from a pertinent issues analy- sis in Tier 1. The project involves work on an operating airport. The airport desires to keep operations and passengers flowing smoothly throughout the construction of the project. In this case, the airport has met with designers who can help define operational goals that can be Table 5-4. Weighted matrix for the example project. Project Delivery Method CMR DB (QBS) Factor Weighted Weighted Selection Factors Score Score Weight Score Score Project complete by November 1, 50 6 300 8 400 20XX Cost not to exceed $200 million 25 6 150 8 200 Minimize impact on operations and 15 10 150 6 90 passengers during construction Minimize staffing requirements 10 8 80 6 60 during design and construction Total Score 100 680 750