Adding an extrapolation model scenario

An extrapolation model (EM) scenario can be used to identify what is required to be forecasted.

To add an extrapolation model scenario

1. Navigate to Workspace > Domains, Services & Applications > Domain > Works.
2. In the Works folder, select the extrapolation model for which you want to add a scenario. The model page is displayed.
3. In the Prediction Scenarios table, click Add scenario.
   

4. On the Add a new scenario page, specify the following:

   • Name: Name of the scenario.
   • Description: Brief description of the scenario.
   • Extrapolation method: Calculates a trendline for each series of the PLA analysis based on the selected method. This selected method overwrites any already defined trendline for the PLA analysis. The available options are:
     • (default) Automatic: BMC Helix Continuous Optimization automatically identifies the specific regression algorithm that minimizes a robust error measure within a standard 80-20 cross-validation procedure, and therefore achieves the best performance in calculating the trendline.
     • Linear regression: Standard linear regression.
     • Robust linear regression: Linear regression process that automatically identifies and removes the outliers.
     • Quadratic regression: Standard second order polynomial regression.
     • Power regression: Fits a power-law trend of the form.
     • Exponential regression: Smooths input data with an exponential IIR filter.
     • Logarithmic regression: Fits a logarithmic trend of the form. 
     • Estimated (regression line)
   • Grouping: Specifies how charts will be grouped and which capacities will be identified as the result of the scenario run. Note that capacities referring to the same set of resources, expressed in terms of different workloads, are to be considered alternatives: for example, a resource in the defined set of resources will overcome the specified threshold if at least one workload reaches the computed capacity value. The available options are:
     • No grouping: Systems or metrics will not be grouped. Only single series is used.
     • Group series by same metric: Multiple series are used, each grouped based on same metric. 
     • Group series by same system/business driver: Multiple series are used, each grouped based on same system or business driver.
     • Group all system/business driver series: All series will be grouped.
   • Threshold: Allows you to set a threshold that will be indicated in the chart.
   • Update policy: Specify whether policy should be updated manually, automatically on page access, or automatically when related analysis changes. 
5. Click Save. A new scenario is created and the scenario details are displayed. 

The following video (4:04) illustrates the process of creating an extrapolation model.

 https://youtu.be/f1mnqbboeY8