The end user can provide a certainty factor alongside an answer whilst running a query to indicate how sure they are about that answer. The ability for an end user to provide a certainty factor can be toggled on or off.
By default, the allowCF function is set to on; to change this setting, open the relationship you want to stop a user from providing a certainty factor for, and under the question properties, toggle the certainty factor to off, as shown in the figure below:
Figure 1: AllowCF switch location
You may want to change the allowCF function dependent on the nature of the relationships in a query. For example, the map below identifies the colour a car used in a crime based on a witness’ testimony. Two different questions are asked to the witness: what is his full name, and what is the colour of the car he saw.
Figure 2: A map to determine what colour car a witness saw
As the crime could have occurred at night, making it difficult to accurately estimate the colour of a car, or as the witness may have forgotten the colour, the Certainty Factor setting is switched on for the relationship. Rainbird allows the user to enter a “Certainty Level” using the Certainty Factor Slider which represents how sure the witness is:
Figure 3: Certainty Factor set to ON
However, for obvious reasons, Rainbird will not ask how sure the witness is of his full name being “Paul Smith Jackson Junior”, so the Certainty Factor setting is switched off for the “has full name” relationship:
Figure 4: Certainty Factor set to OFF
Rainbird will provide an outcome with a level of certainty., which will vary depending on the level of certainty input by the user:
Figure 5: A possible outcome, with an overall certainty factor of 80%
More information on how Rainbird processes certainty can be found in the overall certainty article.
The RBLang below will generate the map used in the example. Click on ‘Export .rbird’ to download the knowledge map or click the ‘Copy RBLang’ button if you want to paste the code directly into Rainbird
Query and Results
When viewing the knowledge map generated by the RBLang below, please run the query on the relationship ‘makes a statement’ for an example of a query that has the certainty factor on and off for different relationships.
Version 1.02 – Last Update: 26/03/2021
