Building a model - Amazon Fraud Detector

Building a model

Amazon Fraud Detector models learn to detect fraud for a specific event type. In Amazon Fraud Detector, you first create a model, which acts as a container for your model versions. Each time you train a model, a new version is created. For details on how to create and train a model using the AWS Console see Step 2: Define model details.

Each model has a corresponding model score variable. Amazon Fraud Detector creates this variable on your behalf when you create a model. You can use this variable in your rule expressions to interpret your model scores during a fraud evaluation.

Train and deploy a model using the AWS SDK for Python (Boto3)

A model version is created by calling the CreateModel and CreateModelVersion operations. CreateModel initiates the model, which acts as a container for your model versions. CreateModelVersion starts the training process, which results in a specific version of the model. A new version of the solution is created each time you call CreateModelVersion.

The following example shows a sample request for the CreateModel API. This example assumes you have created an event type sample_registration. For additional details about creating an event type, see Create event types.

import boto3 fraudDetector = boto3.client('frauddetector') fraudDetector.create_model ( modelId = 'sample_fraud_detection_model', eventTypeName = 'sample_registration', modelType = 'ONLINE_FRAUD_INSIGHTS')

Train your first version using the CreateModelVersion API. TrainingDataSource and ExternalEventsDetail specify the source and Amazon S3 location of the training data set. TrainingDataSchema specifies how Amazon Fraud Detector should interpret the training data, specifically which event variables to include and how to classify the event labels.

import boto3 fraudDetector = boto3.client('frauddetector') fraudDetector.create_model_version ( modelId = 'sample_fraud_detection_model', modelType = 'ONLINE_FRAUD_INSIGHTS', trainingDataSource = 'EXTERNAL_EVENTS', trainingDataSchema = { 'modelVariables' : ['ip_address', 'email_address'], 'labelSchema' : { 'labelMapper' : { 'FRAUD' : ['fraud'], 'LEGIT' : ['legit'] } } }, externalEventsDetail = { 'dataLocation' : 's3://bucket/file.csv', 'dataAccessRoleArn' : 'role_arn' } )

A successful request will result in a new model version with status TRAINING_IN_PROGRESS. At any point during the training, you can cancel the training by calling UpdateModelVersionStatus and updating the status to TRAINING_CANCELLED. Once training is complete, the model version status will update to TRAINING_COMPLETE. You can review model performance using the Amazon Fraud Detector console or by calling DescribeModelVersions. For more information on how to interpret model scores and performance, see Model scores and Training performance metrics.

After reviewing the model performance, activate the model to make it available to use by Detectors in real-time fraud predictions. Amazon Fraud Detector will deploy the model in multiple availability zones for redundancy with auto-scaling turned on to ensure the model scales with the number of fraud predictions you are making. To activate the model, call the UpdateModelVersionStatus API and update the status to ACTIVE.

import boto3 fraudDetector = boto3.client('frauddetector') fraudDetector.update_model_version_status ( modelId = 'sample_fraud_detection_model', modelType = 'ONLINE_FRAUD_INSIGHTS', modelVersionNumber = '1.00', status = 'ACTIVE' )