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How to Train
Your Classifier:
Create a Serverless Machine Learning System
with AWS and Python
PyData ✤ November 27th, 2017 ✤ [email protected]
Tags
Why do you want tags
on your text content?
● Search, navigation,
recommendations
● Aggregation, routing
● Discoverability○ properties
○ relationships
Taxonomy
TaxonomyJordan Larson
<http://cv.ap.org/id/9A7FD8FA87AD4A43BDD522B65147A808> ,
ap:associatedState <http://cv.ap.org/id/8083[Nebraska]43E>;ap:displayLabel "Jordan Larson (Women's volleyball)"@en;
ap:hometown "Hooper, NE"@en;
ap:olympicTeam2016 <http://cv.ap.org/id/46[United States Olympic Team]B73H>;ap:sport <http://cv.ap.org/id/DA[Volleyball]C8EA>;dbprop:birthdate "1986-10-16"^^xsd:date;dcterms:created "2012-07-11T14:30:26-04:00"^^xsd:dateTime;dcterms:modified "2017-07-25T10:37:49-04:00"^^xsd:dateTime;
a <http://cv.ap.org/c/ProfessionalAthlete>, skos:Concept;
skos:broader <http://cv.ap.org/id/384[Professional Athlete]88>;skos:definition "American volleyball player."@en;skos:inScheme <http://cv.ap.org/a#person>;
skos:prefLabel "Jordan Larson"@en;foaf:gender "Female"@en.
Applying taxonomy to textManually
Airlines Industry
Pan American Airlines Co.
Travel
<Hurricane Harvey>
(AND,
(MINOC_2,
(SENT,
(NOTIN,
(OR,"Harvey_C","HARVEY_C"),
(OR,"[Fullname
female]","[Fullname
male]","[Person]")),
(OR,"texas","landfall","storm",
"hurricane","nws","National weather
service","evacuate@","surge@","flood@",
"rain@N","coastal","sandbag@N"...
)
)
)...
Applying taxonomy to textRules-based classifier
https://www.flickr.com/photos/notionscapital/15556898221/
Applying taxonomy to textStatistical classifier
Training data
Training engine Trained model
AP Metadata ServicesTag with AP taxonomy
APMS Custom TaggingSimple four step REST API
Add your own tags and taxonomy
Let’s create a classifier! For dragons
What if l like the AP Taxonomybut I want to classify with some additional tags?
In this case, documents about dragons
A taxonomy of dragons
(borrowed from screencrush.com)
New documents about dragons
To be classified
A map (with some * )
A fully automated workflow for training and deploying a Lambda-based classifier
Sadly, the expression hic sunt
dracones (here be dragons) is an
anachronism, but it does appear
at least once, on the Hunt-Lenox
globe (ca 1510).
The Hunt-Lenox Globe (NYPL)
* Dragon emojis indicate problems found and (mostly) solved
Step Functions
Client
EC2
Auto Scaling
Download training data
Download dependencies
Train model
Deploy model
EC2 classifier.py
classifier.pkl
tags.json
API Gateway
Lambda
Workflow Scaling Worker Classifier
Creating a classifier
A Lambda-based classifier
• AWS Lambda: run event-driven code without provisioning or managing a server or servers
•Cost efficient solution to ensure capacity meets demand
• What do we need?• Code to invoke classifier and return results to user
• Code dependencies (e.g. scikit-learn)
• Other supporting artifacts (the trained model, the taxonomy)
• Permissions for Lambda function to interact with other AWS services
• API endpoint for accessing Lambda function
Step Functions
Client
EC2
Auto Scaling
Download training data
Download dependencies
Train model
Deploy model
EC2 classifier.py
classifier.pkl
tags.json
API Gateway
Lambda
Workflow Scaling Worker Classifier
Processing user requests
Processing user requests
Validate and trainAdding complexity: a workflow for algorithm selection
AWS Step Functions: use visual workflows to coordinate microservices into a single application
Triggers auto-scaling,
sends training request
to worker in the cloud.
Step Functions
Client
EC2
Auto Scaling
Download training data
Download dependencies
Train model
Deploy model
EC2 classifier.py
classifier.pkl
tags.json
API Gateway
Lambda
Workflow Scaling Worker Classifier
Training and deploying
Training in the cloud
• AWS EC2: scalable computing capacity in the cloud
• Register an Amazon Machine Image (AMI) specifically for training
•Speeds up provisioning your server
• Ensures versions match between dependencies and your model•Prepare dependencies ahead of time to beat AWS Lambda’s size limits
•If you are using scikit-learn, sklearn-build-lambda can generate an appropriately sized zip
• Save model and taxonomy to disk, add to dependency zip
Automating deployments• Serverless Framework: Node.js
application for rapid deployment of serverless architectures
• Simplifies the task of creating (and deleting) our classifier Lambdas•Provider agnostic, though you may not be•Zip artifact support for Lambda creation
Step Functions
Client
EC2
Auto Scaling
Download training data
Download dependencies
Train model
Deploy model
EC2 classifier.py
classifier.pkl
tags.json
API Gateway
Lambda
Workflow Scaling Worker Classifier
Classifying with AWS Lambda
Classifying with AWS Lambda
• Be mindful of cold starts•Allocating more memory may help
• Store large models in S3 and take advantage of container reuse•Download assets to /tmp•Check /tmp for cached data before invocation
Item Limit
Deployment package (compressed) 50MB
Deployment package (uncompressed) 250MB
Non-persistent disk space in /tmp 500MB
Predicted Eagles
Predicted Doves
PredictedPigeons
Sum of items
= 300
Actual Eagles
95 3 2 100 Eagles
Actual Doves
3 72 25 100 Doves
ActualPigeons
2 23 75 100 Pigeons
How do I measure results?Confusion matrix
How do I measure results?
Measure your model’s performance per class• Precision (number of correct predictions divided by the total number in the dataset)
• Recall (number of correct positive predictions divided by the total number of positives)
Predicted
Eagles
Predicted
Doves
Predicted
Pigeons
Sum of items
= 300
Actual
Eagles95 3 2 100 Eagles
Actual
Doves3 72 25 100 Doves
Actual
Pigeons2 23 75 100 Pigeons
Model accuracy:
242 / 300 = 80%
How do I improve results?
Training data• Correctly tagged - quality matters• Quantity matters too - as long as it’s ‘good’ data!• Balanced training sets across classes
How do I improve results?
Taxonomy• Clean taxonomy nodes and structure• Distinct semantics, use relationships• Avoid overlapping concepts between nodes
Thank You!
Learn more about AP Metadata Services
https://developer.ap.org/ap-metadata-services