The first step in the Portfolio Definition is inserting the Root Node for the new Portfolio: On the new Portfolio Editor screen select the New Portfolio option from the Main Tool Bar or the File pull-down menu. The system inserts the Root node, naming it New_Portfolio.
The system will not allow you to save portfolios under the default name. To name a new Portfolio:
1. Double click on the Root Node’s nametag, switching it into editing mode. You can also highlight the node and use the Rename function available via File or Right-click menus.
2. Type in a name for your new Portfolio – sample_portfolio in our example and hit Enter. An asterisk next to the Portfolio name indicates that the Portfolio can be SAVED at this point.
Root Node Properties Setup
A crucial step in the Portfolio setup is defining the Root Node’s properties. The Root Node properties include the following mandatory steps:
▪ Root Node (Portfolio) description
▪ Data Models Selection
▪ Portfolio Levels names and descriptions setup:
– The portfolio level is generated by the system and bears the name of the entire Portfolio.
– Additional levels must be created and named reflecting their purpose.
▪ Execution Algorithm selection
Other parameters may include:
▪ Additional columns setup
▪ Parameters setup – various parameters to increase the efficiency of the Portfolio execution.
▪ Logical Conditions setup – inserting logical conditions on the Portfolio level will create a subset of data that allows narrowing down the amount of data to be processed.
▪ Actions Setup – Action is a statement that defines rules for populating Additional columns. It is performed at the Node Properties panel’s Action tab (see below).
Portfolio Node Description
The node Description input field is located to the right of the Portfolio Structure tab’s Tool Bar (Fig.). The node description you enter here will appear in lookup windows and in the screen tips.
To enter the description, click on the input area and type in the node’s description.
Note: Every node within the Portfolio should be assigned a description.
Data Models Selection
The second step in the Portfolio properties setup is Data model selection. The data model is a data set containing at least one Continuous or Segmented data source e.g. transactions, market data, and auxiliary sources providing additional transactional data (if required) and most importantly the control tables for lookups (see Data Model Editor section of the Data Management chapter of this manual).
Data Model selection takes place on the Models tab. To select models for the Portfolio Node:
1. Open the Models tab.
2. On the Models, tab click on the Models Lookup button. This will open the lookup listing all data models available for your selection.
3. Select a model (transactions in our example) and click OK to close the lookup and return to the Portfolio Node Properties screen. Use the Ctrl button on your keyboard to do multiple select if you are adding more than one data model.
The Models Tab’s grid displays the Data Model selected for the Sample Portfolio.
In our Sample Portfolio we will be using only one Data Model. Therefore then Requires all models for execution switch will remain to be set on ‘Yes’.
To remove data models from the tab’s grid
1. Highlight models you want to remove
2. Press the Delete Models button.
Portfolio Levels Setup
Portfolio Level names are used to identify the hierarchical components of the Portfolio in the resulting table.
You build Portfolio levels by inserting and subsegmenting nodes forming the structure of the Portfolio.
Each level will be represented by a column in the Resulting Table generated as the result of the Portfolio Execution. Level names will become headers of these columns.
Note: If you do not set up the levels, no corresponding columns will be created in the resulting source table and no corresponding control tables will be added to the resulting Data Model.
Portfolio Levels tab allows you to create as many levels as required by your Portfolio design. Tab’s tool bar provides functionality to add/insert rows in the grid, copy/paste rows between portfolios.
Our Sample Portfolio structure includes three levels: Segments (1), Subsegments (2) and Entries (3).
To create levels:
1. Open the Levels tab.
2. Click on the Add button of the Levels tab’s tool bar. A row appears in the field.
3. In the Level Name field type in the new entry (report_schedule in our example).
Note: When naming levels avoid using UPPER CASE. These names will be used by the case-sensitive databases, which may not accept upper case characters in column names.
4. Click on the Description field and type in the description for the Segments Level name (Schedule in our example).
Note: The Description you enter here will appear in the Control Table generated during the Portfolio save. This Control table can be enabled (made visible) on the Header Manager.
5. Default Value field contains the default value you want to appear in the level column in the absence of generated data. If you do not enter anything, the field will contain no entries. Since the Level 1 (schedule) and Level 2 (report line) are sufficiently high in granularity, most probably every transaction will fall into one of these categories and the level columns will have some sort of value. Therefore this step could be skipped for the setup of Level 1 and 2.
Level three however may be absent in some nodes. Therefore, to avoid empty cells, you should put NA (non-applicable) value as the default.
6. Repeat the above steps for each additional level. At the end of the procedure the Levels tab’s grid should look as shown on the illustration below.
Additional Columns Setup
In our Sample Portfolio we will create three Additional columns named as following:
1. Pd column (default probability)
2. Pd_gty (guarantor default probability)
3. Pd_final (final default probability)
Then we would like to set up actions to populate these columns. As the result of the exercise:
1. pd (default probability) column will be populated with data from the facility_aggr.pd column of the original source
2. pd_grnt (guarantor default probability) column will be populated with the contents of the guaranty_aggr.pd column of the original source table
Note: We want to transfer data from the source table columns into newly created ones in order to optimize the execution process by avoiding extensive joints to the original source that may significantly slow down the system.
3. pd_final (final default probability) column will contain the data generated based on the results of the previous two actions.
To create an Additional column for the Default Probability:
1. On the Additional Column Tab’s Tool Bar press button to insert a row into the Additional Columns tab’s grid (Fig.). The row has five mandatory fields essential for the Additional Column setup:
a. Column Name – by which it will be recognized by the database
b. Column Description – the column header on the viewer screens
c. Data Type
d. Data Size
e. Default Value.
2. Type ‘pd’ (use low case and underscores when naming columns) into the Column field and Default Probability in the Description field.
Note: Avoid using special characters (i.e. ( ) * %, etc.) when creating column names and descriptions.
3. Select data type – FLOAT in our example – from the Type field’s combo box menu.
4. Since the Data in the pd Column will belong the FLOAT type, the Size parameter is irrelevant.
5. The default value parameter is optional. We enter ‘0’ here, which means that if no action is set on the Portfolio level default probability will equal zero.
Note: The Action that will be assigned to this column on the subsequent levels will override the default value.
Step 5 concludes basic pd column setup.
Repeat the above steps for pd_gty and pd_final columns. At the end of this process your Additional Column tab’s grid should look like shown on the illustration below (Fig).
Optional Additional Column Parameters Setup
The system allows you to set up, if applicable, a lookup for the Additional column and fine-tune its default relationship with the source or the target table. You can therefore:
1. Provide a lookup for the Additional Column.
2. Add a Lookup Source to the resulting Data Model
3. Establish Optional Joint Constraint
4. Establish Optional Joint Constraint
5. Set up the Relationship to Parent (source)
Additional Column Lookup Setup
The system allows you to set up the lookup (if data format allows) for the newly added column.
The button opens a lookup window where you can select a Control source to serve as the Additional Column lookup. This action automatically fills the Value Column and Description Column fields with the respective Control Source’s column names (Fig. 4-37). Arrow buttons enable you to modify the selection of system-provided column names.
Add a Lookup Source to the resulting Data Model
A check box appears in this field when the Lookup source is selected. Putting a mark into the field’s check box inserts a default relationship to the parent column into the last field of the column setup grid (Fig.).
Default Lookup-Parent source relationship is set automatically when you use Add Lookup Source to Model option
The result will be that the Control Table selected for the Additional column will appear on viewers.
Establish Optional Joint Constraint
Optional Joint Constraint is used in conjunction with the Add a Lookup Source to the resulting Data Model parameter in order to, for example, limit information displayed in the Lookup column or correct possible column name discrepancies by entering an SQL expression into the Optional Joint Constraint field.
Relationship to Parent Setup
Relationship to Parent (source) is set up automatically by the system when you use Add a Lookup Source to the resulting Data Model option (see above). If you are not satisfied with the default relationship, you can change it by selecting another option from the Arrow button menu at the Relationship to Parent field.
Note: In order to populate additional columns, portfolio action must be written for each of them (see Portfolio Action section below).
Note: Consult Axiom SL if you are not clear on the above-described procedures.
On the Parameters tab (Fig.) you define miscellaneous optional parameters of the Portfolio:
DB Source in our example should be set on CV_UAT.
Storage Type In our Sample Portfolio should be set to CONTINUOUS_PARTITION.
Execution Algorithm In case of our Sample Portfolio we should be set to: optimized_for _few_ aggregations.
Custom Portfolio Result Alias input field should remain blank.