Explaining Machine Learning Models by Tracked Behavioral Latent Features
AssigneeFair Isaac Corporation
InventorsScott Michael Zoldi, Chahm An
Life of this patent
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Abstract
A system and method to explain model behavior, which can benefit not only those seeking to meet regulatory requirements when using machine learning models but also help guide users of the model to assess and increase robustness associated with model governance processes. The method described utilizes changes in behavior of a time series to identify the latent factors that drive explanation.
Claims18
A method comprising:
- receiving, by one or more computer processors, a time series of input variables representing a time-ordered sequence of Observations associated with an entity;
- generating, by the one or more computer processors, a word dictionary for the input variables, the word dictionary representing a unique sequence of event words across the entity and a group of other entities
- generating, by the one or more computer processors, a set of archetypes from the unique sequence of event words, where topic modeling associates a loading of archetypes associated with each event word;
- generating, with a topic modeling module executed by the one or more computer processors, a vector of weights representing a distribution of the time series of input variables aligning with each of a given number of latent topic variables, the given number of topic variables corresponding to latent features of behavior based on variable values;
- producing, according to a machine learning model executed by the one or more computer processors, a detection score associated with the entity for each input event in the time-ordered sequence of observations;
- generating, by the one or more computer processors, one or more explanations, each explanation describing a reason corresponding to the produced detection score;
- filtering, through comparison against profiled average values of latent topic variables by the one or more computer processors, the one or more explanations to generate a filtered list of explanations according to archetype, the filtered list providing a list of archetypes associated with the detection score and increasing in relevance of behavior;
- and
- ranking, according to a closeness of a bin of historical latent topic variables' expected score to the current score on the event, the filtered list of archetypes and associated reasons that most affect the detection score.
A computer program product comprising a non-transitory machine-readable medium storing instructions that, when executed by at least one programmable processor, cause the at least one programmable processor to perform operations comprising:
- receive a time series of input variables representing a time-ordered sequence of observations associated with an entity;
- generate a word dictionary for the input variables, the word dictionary representing a unique sequence of event words across the entity and a group of other entities
- generate a set of archetypes from the unique sequence of event words, where topic modeling associates a loading of archetypes associated with each event word;
- generate, with a topic modeling module, a vector of weights representing a distribution of the time series of input variables aligning with each of a given number of latent topic variables, the given number of topic variables corresponding to latent features of behavior based on variable values;
- produce, according to a machine learning model, a detection score associated with the entity for each input event in the time-ordered sequence of observations;
- generate one or more explanations, each explanation describing a reason corresponding to the produced detection score;
- filter, through comparison against profiled average values of latent topic variables, the one or more explanations to generate a filtered list of explanations according to archetype, the filtered list providing a list of archetypes associated with the detection score and increasing in relevance of behavior;
- and
- rank, according to a closeness of a bin of historical latent topic variables' expected score to the current score on the event, the filtered list of archetypes and associated reasons that most affect the detection score.
A system comprising:
- a programmable processor;
- and
- a non-transitory, machine-readable medium storing instructions that, when executed by the programmable processor, cause the at least one programmable processor to perform operations comprising:
- receive a time series of input variables representing a time-ordered sequence of observations associated with an entity;
- generate a word dictionary for the input variables, the word dictionary representing a unique sequence of event words across the entity and a group of other entities
- generate a set of archetypes from the unique sequence of event words, where topic modeling associates a loading of archetypes associated with each event word;
- generate, with a topic modeling module, a vector of weights representing a distribution of the time series of input variables aligning with each of a given number of latent topic variables, the given number of topic variables corresponding to latent features of behavior based on variable values;
- produce, according to a machine learning model, a detection score associated with the entity for each input event in the time-ordered sequence of observations;
- generate one or more explanations, each explanation describing a reason corresponding to the produced detection score;
- filter, through comparison against profiled average values of latent topic variables, the one or more explanations to generate a filtered list of explanations according to archetype, the filtered list providing a list of archetypes associated with the detection score and increasing in relevance of behavior;
- and
- rank, according to a closeness of a bin of historical latent topic variables' expected score to the current score on the event, the filtered list of archetypes and associated reasons that most affect the detection score.
Dependencies are inferred from the claim text.