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54 Mean Variance Person Hours Person Hours Person Hours Person Hours Alternative Traveled of Delay Traveled of Delay Do Nothing 1,230,000 61,500 184,500 15,375 Alternative A 1,199,250 30,750 119,925 6,150 Alternative B 1,214,625 46,125 145,755 9,225 Alternative C 1,223,850 55,350 171,339 5,535 Exhibit 7.3. Example results of alternatives evaluation. the lowest mean person-hours of delay. If simply looking at costs and achieving each objective). The relative weight of the variance of the delay, then you would select Alternative C each cost and each objective is combined to yield a single nu- since it produces the lowest variance in delay. merical value for each alternative. The recommended alter- The analyst needs to introduce other information such as native is the one with the best overall numerical value. monetary, societal, and environmental costs to the evaluation of alternatives. This might be done through a cost-effectiveness 7.6 Develop Improvement Program analysis over the lifetime of each alternative. There are several references available for guidance on conducting this type of Once the best alternative has been selected it is necessary to analysis. They include: develop a program for implementing the improvements. This program identifies responsible agencies, sources of funds, and 1. Economic Analysis Primer, U.S. Department of Trans- a schedule for improvements. An implementation monitor- portation, Federal Highway Administration, Office of ing program is useful to ensure that the improvements are Asset Management, FHWA-IF-03-032 (web document), implemented as planned. August 2003. It is available at: http://www.fhwa.dot.gov/ infrastructure/asstmgmt/primer.htm. 7.7 Evaluate Effectiveness 2. NCHRP Synthesis 142: Methods of Cost-Effectiveness of Implemented Solutions Analysis for Highway Projects, Transportation Research Board, Washington, D.C. 1988. An evaluation of the effectiveness of the solution(s) that 3. AASHTO Red Book American Association of State High- have been implemented can be conducted using the before and way and Transportation Officials: A Manual on User Bene- after methods described in Chapter 4. Because this requires fit Analysis of Highway and Bus Transit Improvements, 1977. forethought in setting up the before/after comparison and (See also final report for NCHRP Project 2-23, Development defining data collection needs prior to actual implementation, of an Update to the 1977 AASHTO Redbook.") the decision to conduct this type of effectiveness evaluation needs to be made early, and certain actions taken before con- A weighting scheme is then developed by the analyst (re- struction of the chosen improvement (or initiation of a new flecting the relative importance to the agency of minimizing service or program, if a noncapital improvement).