Office of Operations
21st Century Operations Using 21st Century Technologies

Operations Benefit/Cost Analysis TOPS-BC User's Manual – Providing Guidance to Practitioners in the Analysis of Benefits and Costs of Management and Operations Projects

Appendix A Frequently Asked Questions

The following represent frequently asked questions regarding TOPS-BC. They are arranged according to the four primary capabilities of the tool. This FAQ sheet is meant to provide a quick guide to common issues that may be encountered by users, such as the correct format for user entered data. Many of these guidance items are also incorporated in the tool itself and may be queried when using the tool by clicking on the FAQ hyperlink associated with many data items.

  1. Investigate the Range of Expected Values Associated with Various TSM&O Strategies
    • What is the source of the individual impact information listed in the look up table?
      • A reference for all data points in the lookup table is included in a hidden column to the immediate right of each data item in the table. Unhide the appropriate column to view the listing of the data sources. See Chapter 3 of the User’s Manual for more information.
    • Can new impact data sources or new strategies be added to the look up table?
      • Chapter 7 of the User’s Manual provides guidance on how the user may update the table or add new strategies to the look up capabilities.
  2. Map Different B/C Methodologies to Your Organizations Needs
    • Do I need to indicate responses to all of the listed criteria?
      • No. You may select as few as one criterion to indicate their preferences.
    • What happens if I’ve entered my preferences for multiple criteria categories, but now no Suggested Methodologies are listed?
      • This likely indicates that are no tools that meet all of the criteria supplied by the user. You should consider modifying their criteria to focus on a smaller number of high-priority criteria for their analysis. Also, you should review their responses for any outwardly incompatible responses (e.g., an analysis needing a high level of confidence in the accuracy of the results but also a low level of resources available to support the analysis).
  3. Estimate Life-cycle Costs of TSM&O Strategies
    • What is the source of cost information?
      • The equipment packages comprising each of the strategies is originally based on data in the ITS National Infrastructure. Equipment cost and useful life information is based on cost data maintained in the U.S. DOT ITS JPO ITS Cost Database.
    • Can the list of equipment associated with a strategy be modified?
      • Yes. If you have better or more locally configured equipment data you want to use, you may replace the default equipment, assuming that the new data is entered in the same format (e.g., equipment name, capital cost, useful life, annual O&M costs). Chapter 7 of the User’s Manual provides a description of how cost items may be added for new strategies the user wants to add to their analysis.
  4. Sketch Planning Benefits Estimation and Comparison with Costs
    • What is the appropriate Length of Analysis Period to use?
      • The length of analysis period is entered as length in number of hours. In order to provide a relevant analysis, the length of the analysis period will match as closely as possible to the expected period in which the strategy is intended to be operating. For example, a ramp metering deployment that is expected to only be operated during a 3-hour peak period should be analyzed using data representing that 3-hour peak period. Once the length of the analysis period is determined, other data inputs should be matched to this analysis period (e.g., capacities, volumes and speeds should represent totals/averages across the entire 3-hour peak period). The length of the analysis data should ultimately be matched with the input data. You should not enter 3-hours as the length of the analysis period and then enter peak hour or daily data for other required inputs. TOPS-BC performs no internal conversion of the entered data, therefore, it is the responsibility of the user to correctly match the data.
    • What is the appropriate capacity and volume to enter?
      • The values entered for capacity and volumes in the individual strategy analysis worksheets should represent the average capacity or volume for the entire facility (all lanes) for the period being analyzed. For example, if only one direction of a roadway is being analyzed, the data should be only for that direction. If both directions are included in the analysis, data representing the entire roadway should be used. Likewise, if the analysis is being conducted for a 3-hour peak period, the capacity should represent the 3-hour peak period for all included roadway lanes. Ideally, the period of analysis will match the operating characteristics of the strategy (i.e., a ramp metering strategy intended to be operated during the 3-hour afternoon peak commute period should use data representing the 3-hour PM peak period in the analysis.
    • What does the “Number of Periods per Year” entry represent?
      • The number of periods per year entry is used to annualize the impact estimated for a single day or period to an annual figure. The number entered should be dependent on the analysis period used and the expected operating characteristics of the strategy being analyzed. A default value of 250 represents that the strategy is anticipated to be utilized on all non-holiday weekdays. This entry can be decreased to represent strategies that are anticipated to be used on fewer days per year (e.g., special events only), or increased to represent multiple periods per day (e.g., a doubling of the default value could be used in conjunction with input data from a single peak period to estimate the impacts of multiple peaks per commute day).
    • Where do the TOTAL AVERAGE ANNUAL COST figures come from in the benefit/cost comparison?
      • Life-cycle cost estimates for the individual strategies are pulled from the Life-cycle Cost Estimation worksheet for the individual strategy. To estimate costs for an individual strategy, visit the appropriate cost estimation worksheet for the individual strategy being analyzed and enter the deployment information as directed in the instructions. If you want to use your own estimated costs in the analysis, you may enter their estimated average annual cost in the green User Input cell for this line item.