The Standard Edition has a simple sensitivity analysis interface. The Manager's edition provides for more detailed "What if" scenarios for balancing software reliability ROI.
The following tab is available only in the Manager's Edition. The defect density improvement feature allows you to identify which practices to embrace so as to meet a specific reduction in escaped defects. Escaped defects has a linear relationship to failure rate. So, if you reduce the escapes by 10% you should reduce the failure rate by 10%. While this feature is typically used to make improvements, it can also be used to identify how to downgrade practices that aren't as sensitive as others. The defect density improvement feature displays the practices that you selected from the Full-scale model. Then it allows you to create a "what if" scenario by changing your inputs (either positively or negatively). The development practices are grouped by category and have different weights. You can use those weights as a guide for identifying the what-if scenario. Keep in mind that the practices selected may not be feasible in the short term - you may
need training and other prequisites to see a reduction in defects from any practice. Also keep in mind, that historically no company in our database was able to reduce defect density by more than 25% within the same release. (It can/will take more than one release to see reduction).