Property Sheets: Node Property Sheet
From DSL
Properties of model nodes can be modified through node property sheets.
Node property sheets can be opened in the following ways.
- . Double-click on a node in the Graph view.
- . Right click on the name of the node in the Tree view or right click on the icon of the node in the Graph view. This will display the Node popup menu. Select Node Properties from the menu.
The property sheets, once opened, consist of several tabs. Various tabs can be accessed by clicking on the tab name.
Enabling Diagnostic features of GeNIe considerably changes the Node Property sheet to accommodate the new options.
The tabs Observation Cost and Documentation are displayed only if diagnostic features are enabled. The General tab is also changed.
See Enabling Diagnosis section for help on how to enable diagnostic features.
Shown below is a snapshot of Node Properties sheet when the diagnostic options are disabled.
Contents |
General Tab:
Shown below is the snapshot of the General tab of the Node Properties sheet when the Diagnostic features are enabled. If the diagnostic features are disabled only the first three elements; i.e. Identifier, Name and Type are displayed.
The appearence of the General tab varies slightly for each diagnostic type of node. The rows of the table represent different states of the variable. To rename a state, double-click on its name and edit the text. The name of a state should follow the syntax of identifiers in programming languages - it should start with a letter followed by letters, digits, and underscore characters.
Identifier: It displays the identifier for the submodel. You can also specify your own identifier. Identifiers must start with a letter, and can contain letters, numerals and the underscore character. The identifier for the submodel shown above is Sub4.
Name: It displays the name for the submodel. You can give your own name for the submodel. It has no limitations like the identifier. The name for the submodel shown above is 'Middle Level'.
Type: It displays the type of the node. The various types supported by GeNIe 2 are:
Chance - General
Deterministic
Decision
Value
You can select the node type during creation by selecting the appropriate icon from the Standard Toolbar.
You can also change a node type after creation by either right clicking on the node in the Graph View and selecting 'Change Type...' from the popup menu or selecting Change Type from the Node Menu in the Menu Bar. It will display a submenu where you can choose the appropriate type for the node. See Change Type... section of Node Menu for more information.
Note: Chance Noisy nodes have to be created by first creating the Chance - General node and then changing its type using the method shown above.
The following elements are displayed only if the diagnostic features are enabled
Diagnostic Type: You can select from the 3 available diagnostic types for the node. The appearance for the General tab for these 3 diagnostic types varies slightly as described below:
Target Diagnostic Type: All operations are enabled.
Observation Diagnostic Type: The Target column and Special Names format drop down list is disabled.
Auxiliary Diagnostic Type: The Target column, Default column and Special Names format drop down list is disabled.
Mandatory Check Box:
This checkbox is used to specify if the node is mandatory. For more information on Mandatory nodes see Mandatory section of Spreadsheet View.
Ranked Checkbox:
This checkbox is used to specify if the node is ranked. For more information on Ranked nodes see Ranked section of Spreadsheet View.
Target name format List:
This specifies the format for the Special Name field for a state. It is enabled only if the diagnostic type for the node is Target.
The available options are:
- . User Defined: You can specify your own special name.
- . Node Name: Use the node name as the special name.
- . State Name: Use the state name as the special name.
- . Node + State Name: Use node and state name. Both names are separated by the ":" (colon) character.
- . Inherited: Use the format set in Fault name format list in the General tab in Network Properties Sheet.
Add State Button: Used to add a state to the node.
Insert State Button: used to insert a state between two states. The new state is inserted above the current state [indicated by the 
icon beside it. ]
Delete State Button: used to delete the currently selected state.
State Name and State ID fields: These fields display the state name and StateID. You can change the name or ID by clicking on the name in the field.
Note: State names and State IDs must be unique for the same node.
Target and Default Checkbox: Used to specify if the state is the target state or default state. These may or may not be enabled depending on the node diagnostic type. For more information on which columns are enabled and disabled..See the Diagnostic type section on this page.
Special Name Field: It displays the Special name for the state. It is enabled only when the diagnostic type for the node is 'Target'. you can select the format of this field from the Special name format list. Please refer to Special name format list above for more information.
Please refer to Enabling Diagnosis section on how to set the Diagnostic types and various check boxes for Diagnosis.
Definition Tab:
The Definition tab allows for modifying the definition of the node. While there are common elements among various definition tabs, there are as many definition tabs as there are combinations of node kinds, domains, and probability types.
Definition tab for Chance Node:
The table specifies the conditional probabilities of various outcomes of the current node for all possible combinations of outcomes of the parent nodes. To modify any probability, double-click on it.
The function of each button is explained below:
: Adds a new state to the end of the list.
: Inserts a new state above the current state. Shortcut: Ctrl+I
: Deletes the current state. Shortcut: Ctrl+D
In general, if you change the number of states for a node, you will have to edit the node's probability table as well as the tables of all its direct descendants. Consequently, you can only edit meaningfully conditional probability tables for a node that has its states defined. The states of its parents have to be defined as well. Any change in these definitions, such as adding or removing a state in a parent node, leads to modification of the dimensions of the conditional probability table and requires adjustment of its numerical parameters.
: Copies the contents of the current field to the clipboard.
: Pastes the contents of the clipboard onto the current field.
: Adds a annotation to the selected field. See Annotations for States section of Annotations for more information. Shortcut: Ctrl+T
: Normalize the state probability values. for the current column. i.e. it makes all the numbers in that column sum to one. Shortcut: Ctrl+N
: Complement the current field with respect to the other probabilities in the column. It simply subtracts the sum of the probabilities in the same column from 1 and adds the remainder to the current field. It will display an error message if the sum of probabilities of the other fields in the column exceeds 1.0. You can solve the problem by normalizing the column. Shortcut: Ctrl+O
Note: The Complement button works only when a single cell is selected from the table.
Tip: You can select the entire spreadsheet by clicking on the Node name, or an entire column by clicking on the state name.
: Show Quick Bars button. This displays colored bars behind the probability value.
: Displays a pie chart distribution of the probabilities for the selected column
The pie chart that is displayed is interactive.
You can modify the probability distribution graphically using the sliders. Drag a slider around the circumference of the pie to increase or decrease the probability distribution for that state. Once you have finished modifying a particular state, you can freeze it by double clicking on the pie area for that state. It will result in that portion of the pie to separate as shown below.
You can continue to modify the other two states using the sliders but now the modifications will not affect the blue state.
: Displays a bar-chart for the probability values for the current column.
The bar chart displayed is interactive.
You can modify the probability distribution graphically using the sliders. Drag a slider horizontally to increase or decrease the probability distribution for that state. Once you have finished modifying a particular state, you can freeze it by double clicking on the bar for that state. Once frozen, a bar will look like the blue bar below:
You can continue to modify the other 2 bars using the sliders, but now the value for the blue bar will remain fixed.
Definition Tab for Determinstic node:
The only Deterministic type of nodes currently implemented is a Discrete deterministic node. Its definition is a truth table - knowing the values of the parents of a deterministic node defines its state. The only difference between a general Chance node and a Deterministic node is that the values in the table of the latter are radio buttons. This is enforced by GeNIe. All editing actions are the same as in general Chance nodes.
Definition Tab for Decison node:
These can be modified in the same manner as in general Chance nodes.
Definition Tab for Value node:
Value nodes are continuous and can assume any real values. When their parents are discrete, each cell in the value node defines a measure of preference of the combination of states of these parent nodes. The fields Min and Max contain the lowest and the highest value in the table respectively. When these values are edited and the Normalize button is pressed, the values in the table are linearly transformed to the new interval. This operation is useful in case the numbers in the table are utilities. Very often a decision modeler wants to have the utility function located in a given interval, usually 0-1 or 0-100.
Observation Cost Tab:
This tab is displayed only if the diagnostic options of GeNIe are enabled. See Enabling Diagnosis section for help on enabling this feature.
The Observation cost tab allows for entering the cost of observing the value of the current node. The cost of performing a test can be expressed on some scale, e.g., time in minutes. Costs can also be entered in the Spreadsheet View. For more information on how to enter Observation Costs in Spreadsheet View see Cost section of Spreadsheet View.
For more information on how to use the Cost of Observation in your network see The Cost Of Observation section in Support for Diagnosis.
The Cost dependencies between nodes can be seen by invoking the Cost Graph View. See the Cost Graph View section of Graph View for more information.
The observation tag is shown below. The cost can be interpreted as:
If the Engine Cover is On, Cost is N/A or none.
If the Engine Cover is Off, cost for using the Oil Ruler is 5.
The cost entered can be any real number or can be 'N/A' when the cost is Not Applicable ( N/A ) for the particular state. You can enter 'na' in shorthand to specify N/A.
The button can be used to specify the minimum and maximum cost for that node. It will display a dialog box as shown below:
You can enter the minimum and maximum cost and click OK. GeNIe will normalize all the values to fit within the specified interval.
Note: The Group Cost check box is enabled only if the current node has more than one child. For more information on how to use Group Costs see Group Costs section of Cost of Observation.
Format Tab:
Shown below is the snapshot of the Format tab. The Format tab is used to specify how the node will be displayed in Graph View. It has a preview window which displays the altered view of the node with the new settings.
Select Font: It is used to select the font of the text displayed within the node. Clicking on this button will cause a standard Font Selection dialog box to be displayed. You can select font type, style and size from this box.
Interior, Text & Border Colors: Clicking on the color filled box will pop-up the color selection palette shown below
You can select any of the 40 palette colors or can select more colors by clicking on More colors. This will display the following dialog box:
You can select any color on the rainbow-like part of the window and then add the selected color to one of the 16 custom colors (by clicking on the button Add to Custom Colors).
Border Width: This allows to change the width (in pixels) of the border. This parameter can be used to change the node visibility in the graph view.
The default width for most nodes is one pixel. Submodel nodes have borders of width two.
Apply To: Clicking on the Apply To button displays the following menu:
You can apply the new settings to either
- . The currently selected node.
- . All nodes in the current submodel [This option is displayed only if the selected node is part of a submodel.]
- . All nodes in the network / main model.
'Defaults:
Clicking on the Defaults button displays the following menu:
Set as Defaults: You can set the new format of the node as the default format for all nodes. All nodes will be now displayed by default in the new format unless the format is changed. This default setting is maintained between multiple sessions of GeNIe.
Set as Defaults ( This Session Only ): The new settings will be stored as defaults for this session only. After you quit and restart GeNIe the previous default settings will be restored.
Restore Defaults: This restores the settings to the defaults settings stored before the changes were made.
Documentation Tab:
This tab is displayed only if the diagnostic options of GeNIe are enabled. See Enabling Diagnosis section for help on enabling this feature.
The Documentation tab is used to enter Description, Question, and Link for node and Description, Fix and Link for state. Definitions of these terms are given in following sections of Spreadsheet View.
- Node Description section of Spreadsheet View.
- Node Question of Spreadsheet View.
- State Description section of Spreadsheet View.
- State Fix of Spreadsheet View.
- Links section of Spreadsheet View.
Entering Node & State description, Node question and State Fix:
Right clicking on the Node name or icon will display the popup menu as shown below:
If you right click on a State name or icon it will display the following menu:
Note: Node Question is enabled only for nodes with diagnostic type as Observation Note: State Fix is only enabled for nodes with diagnostic type as Target
Selecting the appropriate option from the menu will open the Description box shown below. Shown below is the Description box for Node Description. The State Description Node Question and State Fix boxes look the same.
Enter the description in the white area and click OK to save the description. Click Cancel to revert to old description. Clicking Delete will clear the description for the node.
Entering Links for Node and State:
Links can be entered for nodes and states by right clicking on the name or icon of the node or state and selecting the Add Link option. This will open the Edit Documentation Link dialog box as shown below:
The Browse... button can be used to select a file from the local computer. When clicked, it will display a File Select dialog box as shown below:
The linked file can be of the standard formats shown above or any other format. You can select the All Files (*.*) option for a file type other than the standard types shown. Select your file, and click Open to return to the previous window. The Title and Link field will now be filled. You can specify your own Title too. You can also specify a link from the Internet by directly entering the URL in the link field. Click on Ok to save the link. Click Cancel to not save the link.
The link will be displayed in the Documentation window under the particular node or state as shown below.
You can right click on the link name to display the menu shown above.
'Open Link: Opens the selected file or link. If it is an URL or a HTML file on disk, it will open a browser window for that file or link. If it is any of the other types, it will try to open the respective program for that file type.
Note: If the file doesnot open as expected, then you donot have the program installed to open that type of file in Windows. Please install the respective program and try again.
Edit Link: You can edit the link to change the Title or the Link fields using this option.
Delete Link: You can delete a link using this option.
User Properties Tab:
The Properties tab allows the user to define properties of the node that can be later retrieved by an application program using SMILE. For example, the following tab for the node 'Node1' contains two properties: author with the value "http://www.sis.pitt.edu/~genie" and location with the value "C:\Program Files\GeNIe 2.0\BNetwork.xdsl". Neither GeNIe nor SMILE use these properties and they provide only placeholders for them. They are under full control and responsibility of the user and/or the application program using the model. GeNIe only allows for editing them.
Add: Used to add a user defined property.
Edit: Used to edit an already defined property.
Delete: Used to delete an already defined property.
Value Tab:
The Value Tab is visible only if an algorithm has been applied to the model i.e. the model has been updated using 
which is found on the Standard Toolbar. See Update Beliefs section of Network Menu for more information on the Update Button.
Shown below is the snapshot of the Value Tab:
You can view the results computed by GeNIe here. Shown above is the Posterior probability distribution of the node. GeNIe shows a list of states of the node along with their probabilities.
