U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
202-366-4000
Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations
 |
| This report is an archived publication and may contain dated technical, contact, and link information |
|
Publication Number: FHWA-HRT-04-044 Date: February 2004 |
Figure 1. Design feature benefits. Diagram. This conceptual graph shows the improved serviceability that can be realized by choosing an enhanced pavement design rather than a standard concrete pavement design. An enhanced pavement design is one that includes higher quality or additional design features in comparison to the standard design. Time or traffic is plotted on the horizontal axis, and the pavement serviceability is plotted on the vertical axis. The chart presents two separate curves representing the performance of the enhanced and standard concrete pavement designs. Both curves decrease in value, but the standard design line decreases more rapidly than the enhanced design line. Both lines extend to a horizontal line representing a critical serviceability. Because the standard design line decreases more rapidly, it intersects the critical serviceability line at an earlier time or traffic level than does the enhanced design line. When each design line intersects the critical serviceability line, a vertical line is extended down to the horizontal axis. The age difference between these two intersection points represents the life extension gained by using the enhanced pavement design. The area between the two curves, and above the critical serviceability line, represents the benefit area of improved performance.
Figure 2. Software main window with the Introduction tab displayed. Screen capture. This figure shows the introductory window from the analysis software tool (this is what the user sees when the software is launched). Traditional Windows ® software menus are shown at the top including the File, Edit, and Help menu options. A set of toolbar buttons for seven unique functions (New, Open, Save, Undo, Redo, Print, and Help) is located immediately below the menus. The remainder of the window area below the button toolbar is occupied by a tab set that is used to organize all of the software inputs. More specifically, the tab set includes individual tabs titled Introduction, Section Definition, Cost/Performance Data Sets, Category Rankings, and Analysis Setup. The Introduction tab is the active tab in the figure. The displayed Introduction tab is divided into two halves. The left side of the tab shows an interactive flowchart that illustrates the typical usage of the analysis tool (the steps a user should follow to design and conduct an analysis). The flowchart is made up of a number of individual boxes that are connected by arrows to illustrate the typical step-by-step process. Progressing from top to bottom in the flowchart, the individual boxes contain the following text:
The right side of the Introduction tab area shows descriptive text associated with the specific analysis step highlighted in the flowchart. In this figure, the Introduction box is highlighted in the flowchart and therefore, introductory information about the tool is displayed in the right side of this tab area. Finally, a Disclaimer button is shown in the lower right corner of this dialog box. Clicking on this button in the software opens a separate window that displays the general FHWA disclaimer.
Figure 3. Contents of the File menu. Screen capture. This figure shows the same screenshot as in figure 2, except the File menu has been activated showing its contents. From top to bottom, the displayed File menu contains the options of New, Open, Save, Save As, Print, Print Preview, Print Setup, the names of the last four viewed databases, and Exit.
Figure 4. Section Definition tab with the Variables secondary tab displayed. Screen capture. This figure shows a screenshot from the analysis software in which the Section Definition tab is displayed. As with all of the primary screenshots from the analysis tool, the traditional Windows menus and custom button toolbar are displayed at the top. At the top of the Section Definition tab area is the bold “Pavement Section Definition” heading. The rest of the tab is then divided into two areas. The area on the left is a list box titled Pavement Section Master List. This list box contains all pavement sections that are created, named, and stored by the user within the current database. Immediately below the Pavement Section Master List is a drop-down list box titled Sort List with “Alphabetically” shown as the selected value. Below the Sort List list box are three buttons titled New, Delete, and Import that are used to manage the contents of the master list. The right side of this Section Definition tab contains the area that shows all of the detailed inputs associated with the section selected in the Pavement Section Master List. At the top of this details area is the Name input box where the user may change the name of the currently selected pavement section. Below the Name input box is a secondary tab set with two tabs titled Variables and Life-Cycle Costs. The Variables tab (displayed in this figure) shows 10 drop-down list boxes associated with the design feature categories of Subgrade, Base/Subbase, Drainage, Thickness/Slab Size, Cross Section, Joints/Load Transfer, Joint Sealing, Shoulders, Strength/Materials, and Smoothness/Ride. These controls are used to define the unique pavement sections that are stored in the master list. Finally, also included on the Variables tab is a Comments input box (used for entering user custom notes) and creation and revision date stamps that show when a particular section was created and revised, respectively.
Figure 5. Example of the Import pop-up dialog box. Screen capture. This figure is an example of an Import pop-up dialog box that is activated when the user clicks the Import button on the Section Definition tab of the software. This pop-up dialog box has text prompting the user to select the sections to be imported. A list of all the sections currently in the Pavement Section Master List is provided. Four buttons, located on the right side of the box, are titled OK, Cancel, Select All, and Select None.
Figure 6. Section Definition tab with the Life-Cycle Costs secondary tab displayed. Screen capture. This figure shows a screenshot from the analysis software that shows additional details of the Section Definition tab. More specifically, this screen shot is similar to that shown in figure 4, except that this figure shows the detailed contents of the Life-Cycle Costs secondary tab. At the top of the Life-Cycle Costs secondary tab is the Global LCC Parameters button. Clicking this button will open a pop-up dialog box containing global life-cycle cost parameters. Immediately below this button are two boxed areas of inputs titled First Rehabilitation and Cost Inputs. The first line of input controls within the First Rehabilitation area includes the text of “Apply first rehabilitation at:” followed by an input box with the number “80” showing. To the right of this input box is a drop-down list box with “percent of expected service life” showing as the selected item. This line of controls is used to define when the first rehabilitation is to be defined (either expressed as a percent of service life or as a specific year). From left to right, the second input line in the First Rehabilitation area includes the text “Assumed rehabilitation life:,” an input box with the number “10” showing, and the text “years” that define the units of the input box. The Cost Inputs area includes three separate lines of inputs. The first line determines the method used to enter costs (I.E., either in terms of a percentage of the initial construction cost or as direct costs). Specifically, this line starts with the text “Enter costs as:” followed by a drop-down list box that defines the input method. In this figure, “percent of initial construction cost” is displayed in the list box. The second line of the Cost Input area is used to enter the details associated with the annual maintenance cost. From left to right this second input line shows the text “Annual maintenance cost:,” an input box with the number “1” showing, and the text “percent of initial dollars per lane-mile cost” that define the units of the input box. The third line of the Cost Input area is used to enter the details associated with the rehabilitation cost. From left to right this third input line shows the text “Rehabilitation cost:,” an input box with the number “10” showing, and the text “percent of initial dollars per lane-mile cost” that define the units of the input box. Finally, at the very bottom of this Life-Cycle Costs secondary tab is a button titled Important Information Regarding Life-Cycle Costs. Clicking this button opens the Help interface and directs the user to a help page specific to the included life-cycle cost method.
Figure 7. Global Life-Cycle Cost Parameters pop-up dialog box. Screen capture. This figure is an example of the Global Life-Cycle Cost Parameters pop-up dialog box that is activated when the user clicks the Global LCC Parameters button on the Section Definition tab of the software. This pop-up dialog box includes three input boxes. In this example, the Analysis Period input box shows a value of “35” years, the Discount Rate shows a value of “4” percent, and the Initial cost of “standard” pavement section input box shows a value of “500,000” dollars per lane-mile. The last input control in the dialog box is a checkbox that indicates whether a salvage value is to be used in the life-cycle cost analysis. Specifically, this checkbox has associated text of “Include a salvage value in the calculations.”
Figure 8. Cost/Performance Data Sets tab with the Grouped Format controls for the Cost Data Sets secondary tab visible. Screen capture. This figure is a screenshot from the analysis software tool with the Cost/Performance Data Sets tab displayed. As with all of the primary screenshots from the analysis tool, the traditional Windows menus and custom button toolbar are displayed at the top. At the top of the Cost/Performance Data Sets tab area is the bold “Cost/Performance Data Set Maintenance” heading. Under this heading are two secondary tabs titled Cost Data Sets and Performance Data Sets (note: the Cost Data Sets tab is selected in this figure). At the top of the displayed Cost Data Sets secondary tab, there are two buttons titled Grouped Format and Tabular Format that determine how the inputs on this tab are displayed. It is the Grouped Format controls that are illustrated in this figure. The rest of the tab is then divided into two areas. The area on the left is a list box titled Cost Data Set Master List. This list box currently shows two defined cost data sets in the list (“Default Cost Set” and “My cost set”). Immediately below the Cost Data Set Master List is a drop-down list box titled Sort List with “Alphabetically” shown as the selected value. Below the Sort List list box are three buttons titled New, Delete, and Import that are used to manage the contents of the master list. The right side of this Cost Data Sets tab contains the Cost Data Set Details area that shows all of the detailed inputs associated with the data set currently selected in the Cost Data Set Master List. At the top of this details area is the Name input box where the user may change the name of the currently selected cost data set. Below the Name box, there is a list box with the 10 different design categories displayed (i.e., Subgrade, Base/Subbase Drainage, Thickness/Slab Size, Cross Section, Joints/Load Transfer, Joint Sealing, Shoulders, Strength/Materials, and Initial Smoothness). In the figure, Base/Subbase has been selected. To the right of this design category list box are the available Base/Subbase-related variables and their associated relative cost input boxes. There are also three sets of input boxes (I.E., a set includes a name and relative cost change input box) associated with user definable custom variables. At the bottom of the column, there is a blank box for comments as well as date stamps associated with the data set creation and revision dates.
Figure 9. Cost/Performance Data Sets tab with the Tabular Format controls for the Cost Data Sets secondary tab visible. Screen capture. This figure shows a screenshot from the analysis software that shows additional details of the Cost/Performance Data Sets tab. More specifically, this screen shot is similar to that shown in figure 8 except this figure shows Cost Data Sets secondary tab with the Tabular Format button selected. With the Tabular Format button selected, the main tab area contains a table that shows the available design feature choices associated with the 10 design categories and their associated user-defined relative cost percentages. More specifically, three columns titled “Variables,” “Default Cost Set,” and “My Cost Set” are displayed in the table. The “Variables” column houses all of the available design features associated with all of the design categories. The “Default Cost Set” and “My Cost Set” columns house the user-defined relative cost values defined and stored in the respective sets (Note: These two cost data sets were those that were shown in the Cost Data Sets Master List in figure 8). This table contains vertical and horizontal scroll bars, therefore, indicating that the that the entire contents of the table are not visible in the space provided. To the right of this table are three buttons titled Add Set, Delete Set, and Export Table that can be used to manage the different cost data sets.
Figure 10. Example of using the provided custom design feature fields to reflect an agency’s custom design features. Screen capture. This figure presents a screenshot from the analysis software tool that shows the use of the custom design variable input fields. More specifically, this figure is exactly the same as the Cost/Performance Data Sets tab displayed in figure 8, but with the first Custom 1 variable field in use. As in figure 8, the Grouped Format controls are illustrated with the Cost Data Set Master List shown on the left and the Cost Data Set Details area shown on the right side of the tab. At the top of this details area is the Name input box where the user may change the name of the currently selected cost data set. Below the Name box, there is a list box with the 10 different design categories displayed (I.E., Subgrade, Base/Subbase Drainage, Thickness/Slab Size, Cross Section, Joints/Load Transfer, Joint Sealing, Shoulders, Strength/Materials, and Initial Smoothness). In the figure, Base/Subbase has been selected. To the right of this design category list box are the available Base/Subbase-related variables and their associated relative cost input boxes. The only difference between this figure and figure 8 is that one of the custom variable boxes for the Base/Subbase design category has been filled in. The variable name input box has changed from “Custom 1” to “8-inch dense-graded aggregate base.” The relative cost percentage has also been entered in as “plus 2.5 percent.”
Figure 11. Example showing chosen relative cost values associated with a 150-millimeter (6-inch) dense-graded asphalt-treated base. Screen capture. This figure presents a screenshot from the analysis software that shows another example of the Cost/Performance Data Sets tab with the Grouped Format button selected. This screenshot is similar to that in figure 8, except that the Cost Data Set Details area (on the right side of the figure) shows information associated with Initial Smoothness. At the top of this details area is the Name input box where the user may change the name of the currently selected cost data set. Below the Name box, there is a list box with the 10 different design categories displayed (I.E., Subgrade, Base/Subbase Drainage, Thickness/Slab Size, Cross Section, Joints/Load Transfer, Joint Sealing, Shoulders, Strength/Materials, and Initial Smoothness). In the figure, the 6-inch dense graded asphalt variable under the Initial Smoothness design feature category has been selected. The right side of the details area contains five different smoothness levels and three user-definable custom variables for which relative cost values may be entered. Specifically, the five different smoothness levels and associated relative cost percentages are the following:
No relative cost values are entered for the Custom 1, Custom 2, and Custom 3 fields.
Figure 12. Example showing defined relative performance values associated with different base type choices. Screen capture. This figure is a screenshot from the analysis software tool with the Cost/Performance Data Sets tab displayed. As with all of the primary screenshots from the analysis tool, the traditional Windows menus and custom button toolbar are displayed at the top. At the top of the Cost/Performance Data Sets tab area is the bold “Cost/Performance Data Set Maintenance” heading. Under this heading are two secondary tabs titled Cost Data Sets and Performance Data Sets (note: the Performance Data Sets tab is selected in this figure). At the top of the displayed Performance Data Sets secondary tab, there are two buttons titled Grouped Format and Tabular Format that determine how the inputs on this tab are displayed. It is the Grouped Format controls that are illustrated in this figure. The rest of the tab is then divided into two areas. The area on the left is a list box titled Performance Data Set Master List. This list box currently shows two defined performance data sets in the list (“Default Performance Set” and “My Performance Set”). Immediately below the Performance Data Set Master List is a drop-down list box titled Sort List with “Alphabetically” shown as the selected value. Below the Sort List list box are three buttons titled New, Delete, and Import that are used to manage the contents of the master list. The right side of this Performance Data Sets tab contains the Performance Data Set Details area that shows all of the detailed inputs associated with the data set currently selected in the Performance Data Set Master List. At the top of this details area is the Name input box where the user may change the name of the currently selected performance data set. Below the Name box, there is a list box with the 10 different design categories displayed (i.e., Subgrade, Base/Subbase Drainage, Thickness/Slab Size, Cross Section, Joints/Load Transfer, Joint Sealing, Shoulders, Strength/Materials, and Initial Smoothness). In the figure, Base/Subbase has been selected. To the right of this design category list box are the available Base/Subbase-related variables and their associated relative performance input boxes. There are also three sets of input boxes (for name and relative performance change) associated with user definable custom variables. The first custom variable name has been changed from “Custom 1” to “8-inch dense-graded aggregate base” to demonstrate the use of these custom fields. At the bottom of the column, there is a blank box for comments as well as date stamps associated with the data set creation and revision dates.
Figure 13. Example showing defined relative performance values associated with different initial smoothness choices. Screen capture. This figure shows a screenshot from the analysis software that shows additional details of the Cost/Performance Data Sets tab. More specifically, this screen shot is similar to that shown in figure 12, except that this figure shows Performance Data Sets secondary tab with the Tabular Format button selected. With the Tabular Format button selected, the main tab area contains a table that shows the available design feature choices associated with Initial Smoothness and their associated user-defined relative performance percentages. More specifically, three columns titled “Variables,” “Default Performance Set,” and “My Performance Set” are displayed in the table. The “Variables” column houses all of the available design features associated with all of the design categories. The “Default Performance Set” and “My Performance Set” columns house the user-defined relative performance values defined and stored in the respective sets (these are the two performance data sets shown in the Performance Data Sets Master List in figure 12). This table contains vertical and horizontal scroll bars, therefore, indicating that the that the entire contents of the table are not visible in the space provided. To the right of this table are three buttons titled Add Set, Delete Set, and Export Table that can be used to manage the different performance data sets.
Figure 14. Category Rankings tab. Screen capture. This figure is a screenshot from the analysis software tool with the Category Rankings tab displayed. As with all of the primary screenshots from the analysis tool, the traditional Windows menus and custom button toolbar are displayed at the top. At the top of the Category Rankings tab area is the bold “Category Ranking Sets Definition” heading and a brief introduction to the tab. The rest of the tab is divided into the Category Ranking Set Master List and Category Ranking Set Details areas. Similar to the other master lists in the user interface, the Category Ranking Set Master List stores all of the created, named, and saved category ranking factor sets. Below the Category Ranking Set Master List is a drop-down list box titled Sort List with “Alphabetically” shown as the selected value. Below the Sort List list box are three buttons titled New, Delete, and Import that are used to manage the contents of the master list. At the top of the Category Ranking Set Details areas is a Name input box where the user may change the name of the currently selected ranking factor set. Below the Name input box is the Variable Weights table where the user defines the individual ranking factors associated with the ten design categories. This table contains two columns titled “Variable” and “Rank.” The “Variable” column contains a sorted list of design features categories that shows (from top to bottom) Joints/Load Transfer, Thickness/Slab Size, Base/Subbase, Drainage, Strength/Materials, Subgrade, Initial Smoothness, Joint Sealing, Cross Section, and Shoulders. In the “Rank” column, ranking factors of 10 to 1 are assigned to these respective design feature categories (going from top to bottom). Also included is a Comments input box (used for entering user custom notes) and creation and revision date stamps that show when a particular ranking factor set was created and revised, respectively.
Figure 15. Example of the Analysis Setup tab. Screen capture. This figure is a screenshot from the analysis software tool with the Analysis Setup tab displayed. As with all of the primary screenshots from the analysis tool, the traditional Windows menus and custom button toolbar are displayed at the top. At the top of the Analysis Setup tab area is the bold “Analysis Sessions” heading and a brief introduction to the tab. The rest of the tab is divided into the Direct Comparison Sessions master list and the Sensitivity Analysis Sessions master list. Similar to the other master lists in the user interface, these lists store all of the created, named, and saved analysis sessions of each type. Below each master list is a drop-down list box titled Sort List with “Alphabetically” shown as the selected value. Below the Sort List list box are three buttons titled New, Delete, and Import that are used to manage the contents of each respective master list. In the upper right corner of this tab there are two buttons titled Back and Next. Selecting an analysis session from one of the master lists and clicking the Next button will take the user to a dialog box where the analysis details are defined.
Figure 16. Example of the Direct Comparison analysis session setup dialog box. Screen capture. This figure is a screenshot from the analysis software tool with the Direct Comparison analysis session setup portion of the Analysis Setup tab displayed. As with all of the primary screenshots from the analysis tool, the traditional Windows menus and custom button toolbar are displayed at the top. Below the main “Analysis Sessions” heading is an input box titled Name along with brief on how to use the controls on this dialog box. The tab is divided into four general areas titled “Step 1: Select Pavement Section A,” “Step 2: Select or Specify Pavement Section B,” “Step 3: Select Other Settings,” and “Optional Information.” The “Step 1: Select Pavement Section A” area contains a drop-down list box from which the user selects the first pavement section (Section A) to be used in the analysis. Below this drop-down list box are the specific design features (for all 10 design categories) that define Section A. The “Step 2: Select or Specify Pavement Section B” area is similar in that it contains a drop-down list box from which the user selects the second pavement section (Section B) to be used in the analysis. Below this drop-down list box are the specific design features (for all 10 design categories) that define Section B. The “Step 3: Select Other Settings” area contains three drop-down list boxes titled Cost Data, Performance Data, and Ranking Data. These drop-down lists are used to define the specific cost data, performance data, and ranking factor sets that are to be used in the analysis. Finally, the “Optional Information” area on the dialog box contains an input box for additional user comments and creation and revision date stamps that show when a particular ranking factor set was created and revised, respectively.
Figure 17. Example of the Sensitivity Analysis session setup dialog box. Screen capture. This figure is a screenshot from the analysis software tool with the Sensitivity Analysis session setup portion of the Analysis Setup tab displayed. As with all of the primary screenshots from the analysis tool, the traditional Windows menus and custom button toolbar are displayed at the top. Below the main heading is an input box titled Name along with brief on how to use the controls on this dialog box. The tab is divided into four general areas titled “Step 1: Select a Pavement Section,” “Step 2: Define Sensitivity Analysis Session,” “Step 3: Select Fixed Settings,” and “Optional Information.” The “Step 1: Select a Pavement Section” area contains a drop-down list box from which the user selects the pavement section that is to be used as the basis of the analysis. Below this drop-down list box are the specific design features (for all 10 design categories) that define this first pavement section. The “Step 2: Define Sensitivity Analysis Session” area is used to define the type of sensitivity analysis that is to be performed. At the top of this area, the Type drop-down list box is shown with “Compare Multiple Sections” shown as the selected value. This indicates that in this example, the user has chosen to compare other pavement sections to the pavement section selected in the step 1 of the analysis setup. Below the Type list box is a table showing the other pavement sections that are available to be included in the analysis. To the left of each available section is a checkbox that the user may check if they want the section to be included in the sensitivity analysis. In this figure, there are two sections shown in this table (“Standard Pavement Section” and “New Section”), both of which have been selected to be included in the analysis. The “Step 3: Select Fixed Settings” area contains three drop-down list boxes titled Cost Data, Performance Data, and Ranking Data. These drop-down lists are used to define the specific cost data, performance data, and ranking factor sets that do not change within the sensitivity analysis. Finally, the “Optional Information” area on the dialog box contains an input box for additional user comments and creation and revision date stamps that show when a particular ranking factor set was created and revised, respectively.
Figure 18. Example of a Sensitivity Analysis comparing both cost and performance data sets. Screen capture. This figure is a screenshot from the analysis software tool with the Sensitivity Analysis session setup portion of the Analysis Setup tab displayed. This figure is very similar to that shown in figure 17. The only difference between this figure and figure 17 is that the sensitivity analysis type (Step 2) is shown as “Compare both Cost and Performance Sets (2-dim).” This indicates that in this example, the user has chosen to investigate the simultaneous impact of different cost and performance data sets on the one pavement section defined in Step 1. Below the “Type” list box are two tables accompanied by the following text “Dimension 1: Check the cost sets you wish to compare” and “Dimension 2: Check the performance sets you wish to compare.” Each of these tables contain lists of the cost data and performance data sets that are available to be included in the analysis. To the left of each available cost or performance data set is a checkbox that the user may check if they want the data set to be included in the sensitivity analysis. In this figure, there are three cost data sets shown (“Default Cost Set,” “Cost Set 1,” and “Cost Set 2”) with only the “Cost Set 1” checked to be included in the analysis. The table of performance data sets includes three entries (“Default Performance Set,” “Performance Set 1,” and “Performance Set 2”) with all three selected to be included in the analysis. The “Step 3: Select Fixed Settings” area contains three drop-down list boxes titled Cost Data, Performance Data, and Ranking Data. Because this analysis type is investigating changes in cost and performance data sets, those to associated drop-down list boxes are disabled in this example. Finally, the “Optional Information” area on the dialog box contains an input box for additional user comments and creation and revision date stamps that show when a particular ranking factor set was created and revised, respectively.
Figure 19. Example of a Full Report summary resulting from a Direct Comparison analysis. Screen capture. This figure is a screenshot from the analysis software tool with the Direct Analysis Results portion of the Analysis Setup tab displayed. As with all of the primary screenshots from the analysis tool, the traditional Windows menus and custom button toolbar are displayed at the top. This dialog box is divided into two main areas: report customizing radio buttons on the left and an area for viewing the compiled output report on the right. The two radio buttons on the left side of the tab are labeled as Full Report and Basic Tables Only. Clicking the Full Report radio button (that selected in the figure) displays all text and tables associated with the Direct Comparison analysis. Clicking the Basic Tables Only would greatly simplify the output results displayed in the window on the right side of this dialog box. Under the Basic Tables Only radio button are four checkboxes titled Cost Details, Performance Details, Benefit Cost Summary, and LCC Analysis Summary. Because the Basic Tables Only radio button is not selected in this figure, these checkboxes are disabled. A portion of an example output report is displayed in the large text box on the right side of this window. There is a scroll bar to the right of the box that indicates that the complete output report is much longer than what is seen in this window.
Figure 20. Example of the Basic Tables Only output report resulting from a Direct Comparison analysis. Screen capture. This figure is similar to figure 19 in that it is a screenshot from the analysis software tool with the Direct Analysis Results portion of the Analysis Setup tab displayed. As with all of the primary screenshots from the analysis tool, the traditional Windows menus and custom button toolbar are displayed at the top. As in figure 19, this dialog box is divided into two main areas: report customizing radio buttons on the left and an area for viewing the compiled output report on the right. The two radio buttons on the left side of the tab are labeled as Full Report and Basic Tables Only. The only difference between this figure and figure 19 is that here the Basis Tables Only radio button is selected and the accompanying Benefit/Cost Summary checkbox is checked. Therefore, the output report visible in the large output report checkbox on the right side of the presented dialog box only contains the benefit/cost-related summary table.
Figure 21. Example of a Detailed Results summary table output resulting from a Sensitivity Analysis session. Screen capture. This figure is a screenshot from the analysis software tool with the Sensitivity Analysis Results portion of the Analysis Setup tab displayed. As with all of the primary screenshots from the analysis tool, the traditional Windows menus and custom button toolbar are displayed at the top. This dialog box is divided into two main areas: a report customizing Detailed Results checkbox on the left and an area for viewing the compiled output report on the right. In the figure the Detailed Results checkbox is selected; therefore, the detailed text and tables associated with the Sensitivity Analysis are shown in the window on the right. Deselecting the checkbox results in only one overall summary table being shown in the results viewing area. A portion of an example output report is displayed in the large text box on the right side of this window. There is a scroll bar to the right of the box that indicates that the complete output report is much longer than what is seen in this window.
Equation 1. The desired number of survey samples, lowercase N, equals the quotient of the product of the estimated standard deviation, sigma, times the number of standard error units, lowercase Z, divided by the required precision or tolerance, T, all raised to the second power.
