What is What-If Analysis?
What-if analysis, in the context of SAP Spend Performance Management, facilitates report-based what-if analysis.
Typical what-if analysis requires a model, which expresses the relationship between input variables and output result. Such a relationship is usually defined by a numeric formula. A simple example of a model is that of mortgage payment calculation. Here the input variables are loan amount, payment term and interest rate, and the output result is the monthly payment, calculated by the mortgage payment formula. A report-based what-if analysis takes advantage of the reporting infrastructure to simplify the what-if analysis for a complex, multi-dimensional data structure.
As with typical what-if analysis, a scenario represents an instantiation of a given what-if model. In the case of mortgage payment calculation model, a 30-year payment term with a 3% interest rate represents one scenario of the model; whereas, a 15-year payment term with a 2.5% interest rate represents another scenario. Similarly, report-based what-if scenarios are variation of corresponding model with various instantiation of input variables. As a result, each scenario has potentially different output result, derived from various input instantiations. If the what-if model is defined on a multi-dimensional data structure, the model calculation will be applied on the operations for the multi-dimensional data structure, such as drill-down, and slice and dice.
(SAP internal reference: https://wiki.wdf.sap.corp/wiki/display/SpendAnalytics/SSA+v3.0+What-If+Simulation)
The following is an demo for the What-If Analysis in SAP Spend Performance Management:
Formula for Buy-Now-Model
Formulat for Buy-Later-Model
Scenario with text input
Scenario with drop-down list input