This post was co-written with Dave Gowel, CEO of RallyPoint. In his own words, “RallyPoint is an online social and professional network for veterans, service members, family members, caregivers, and other civilian supporters of the US armed forces. With two million members on the platform, the company provides a comfortable place for this deserving population to connect with each other and programs designed to support them.”
All those who serve – and those who support them – often face a variety of employment challenges when a servicemember transitions back into civilian life. RallyPoint has identified the transition period to a civilian career as a major opportunity to improve the quality of life for this population by creating automated and compelling job recommendations. However, the team historically employed a rule-based curation method to recommend jobs throughout its user experience, which doesn’t allow members to get job recommendations personalized to their individual experience, expertise, and interests.
“To improve this experience for its members, we at RallyPoint wanted to explore how machine learning (ML) could help. We don’t want our servicemembers, veterans, and their loved ones to waste time searching for a fulfilling civilian career path when they decide to leave the military. It should be an easy process. We want our members to tell us about their military experiences, any schools they’ve attended, and their personal preferences. Then by leveraging what we know from our millions of military and veteran members, relevant open jobs should be easily surfaced instead of laboriously searched. This free service for our members is also expected to drive revenue by at least seven figures from employers seeking the right military and veteran talent, allowing us to build more free capabilities for our members.”
This blog post summarizes how the Amazon Machine Learning Solution Lab (MLSL) partnered with RallyPoint to drive a 35% improvement in personalized career recommendations and a 66x increase in coverage, amongst other improvements for RallyPoint members from the current rule-based implementation.
“MLSL helped RallyPoint save and improve the lives of the US military community. Fortunate to work on multiple complex and impactful projects with MLSL to support the most deserving of populations, RallyPoint accelerated growth in multiple core organizational metrics in the process. MLSL’s high caliber talent, culture, and focus on aiding our realization of measurable and compelling results from machine learning investments enabled us to reduce suicide risk, improve career transition, and speed up important connections for our service members, veterans, and their families.”
The following sections cover the business and technical challenges, the approach taken by the AWS and RallyPoint teams, and the performance of implemented solution that leverages Amazon Personalize.
Amazon Personalize makes it easy for developers to build applications capable of delivering a wide array of personalization experiences, including specific product recommendations, personalized product re-ranking, and customized direct marketing. Amazon Personalize is a fully managed ML service that goes beyond rigid, static rule-based recommendation systems by training, tuning, and deploying custom ML models to deliver highly customized recommendations to customers across industries such as retail and media and entertainment.
Business and Technical challenges
Multiple business challenges inspired this partnership. The most pertinent was the clickthrough rate on the top 10 recommended jobs on the RallyPoint website. RallyPoint analyzed user engagement within their platform and discovered that they needed to increase the number of relevant jobs that users are clicking. The idea is that the more relevant a recommended job is, the higher the likelihood of members applying to those jobs, leading to improved employment outcomes.
The next challenge was to increase the engagement by members on job services offered on the site. RallyPoint offers the opportunity for people to “Build your brand and engage the military community, advertise your products and services, run recruitment marketing campaigns, post jobs, and search veteran talent.” They once again identified an opportunity to apply AWS Personalize to help more people transition to civilian life, and sought to improve their click-to-customer conversion numbers, leading to better outcomes for RallyPoint’s direct customers.
From a technical perspective, like many traditional recommender system problems, data sparsity and a long tail was a challenge to overcome. The sample set of de-identified, already publicly shared data included thousands of anonymized user profiles, with more than fifty user-metadata points, but many had inconsistent or missing meta-data/profile information. To tackle this, the team leveraged the Amazon Personalize cold start recommendation functionality for relevant users.
To solve the problem, MLSL collaborated with RallyPoint to construct a custom Amazon Personalize pipeline for RallyPoint. Some of the services used include Amazon Simple Storage Service (Amazon S3), Amazon SageMaker Notebook Instances, and Amazon Personalize. The following diagram illustrates the solution architecture.
The anonymized raw data used for the solution consisted of a history of interactions with job postings along with metadata on user profiles and job positions. This was stored in S3. The MLSL team used Amazon SageMaker Notebook Instances to prepare data as input to Amazon Personalize. This step included data preprocessing, feature engineering, and creating dataset groups and schemas required for Amazon Personalize. For more information refer to Creating a Custom dataset group.
The next step was to create a solution in Amazon Personalize. A solution refers to the combination of an Amazon Personalize recipe, customized parameters, and one or more solution versions. For more information refer to Creating a solution. The team used the User-Personalization recipe to generate user-specific job recommendations for users in a validation set. The Amazon Personalize outputs, including the job recommendations and performance metrics, are stored in an Amazon S3 bucket for further analysis.
In the final step, the team used a notebook instance to prepare the output recommendations for external evaluation by human annotators, as described in the Using Domain Experts section.
Evaluation of Amazon Personalize results
The performance of an Amazon Personalize solution version can be evaluated using offline metrics, online metrics, and A/B testing. Offline metrics allow you to view the effects of modifying hyperparameters and algorithms used to train your models, calculated against historical data. Online metrics are the empirical results observed in your user’s interactions with real-time recommendations provided in a live environment (such as clickthrough rate). A/B testing is an online method of comparing the performance of multiple solution versions to a default solution. Users are randomly assigned to either the control (default) group or one of the treatment (test) groups. The control group users receive recommendations from the default solution (baseline), whereas each of the treatment groups interact with a different solution version. Statistical significance tests are used to compare the performance metrics (such as clickthrough rate or latency) and business metrics (such as revenue) to that of the default solution.
Amazon Personalize measures offline metrics during training a solution version. The team used offline metrics such as Mean Reciprocal Rank (MRR), normalized discounted cumulative gain (NCDG@k), Precision@k, and Coverage. For the definitions of all available offline metrics, refer to Metric definitions.
Although Amazon Personalize provides an extensive list of offline metrics that the team can use to objectively measure the performance of solutions during training, online metrics and A/B testing are recommended to track and validate model performance. One caveat to these tests is that they require users to interact with Amazon Personalize recommendations in real time. Because the RallyPoint Amazon Personalize model wasn’t deployed prior to this publication, the team didn’t have results to report for these tests.
Using Domain Experts
A/B testing is the preferred method of analyzing the quality of a recommendation system however, using domain experts to annotate recommendations is a viable precursor. Since online testing was not an option, to test the robustness of the recommendations, the team asked domain experts in RallyPoint to annotate the recommendations generated by the models and count the number of job positions the experts agreed should be recommended (given a user’s information and indicated preferences) as the number of “correct” recommendations. This metric was used to compare solution versions. A popularity solution (the current rule-based criteria) was used as a baseline which consisted of recommending top five most popular job positions to every user. Moreover, a solution with default settings was used as another baseline model called Amazon Personalize baseline solution.
Using the best performing model resulted in a 35% improvement in the number of “correct” recommendations over the Amazon Personalize baseline solution and a 54% improvement over the popularity solution. The team could also achieve a 66x improvement in coverage, 30x improvement in MRR, and 2x improvement in precision@10 when compared to the popularity solution. In addition to the popularity solution, the team observed up to 2x increase in MRR and precision@10 when compared to the Amazon Personalize baseline solution.
RallyPoint recognized an opportunity to better serve their customers with more personalized career recommendations. They began their user personalization journey with customer obsession in mind, partnering with the Machine Learning Solutions Lab. RallyPoint now has the opportunity to give their users more valuable career recommendations, through this solution. Incorporating this improved recommendation system into their website will result in RallyPoint users seeing more relevant jobs in their career feed, easing the path to more fulfilling careers and an improved quality of life for their members.
Use Amazon Personalize to provide an individualized experience for your users today! If you’d like to collaborate with experts to bring ML solutions to your organization, contact the Amazon ML Solutions Lab.
For more information about Amazon Personalize, see the following:
About the Authors
Dave Gowel is an Army veteran and the CEO of RallyPoint. Dave is a graduate of West Point and the US Army Ranger School, served in Iraq as a tank platoon leader, and taught as an assistant professor at the Massachusetts Institute of Technology ROTC program. RallyPoint is the third technology company for which Dave has been CEO.
Matthew Rhodes is a Data Scientist working in the Amazon ML Solutions Lab. He specializes in building machine learning pipelines that involve concepts such as natural language processing and computer vision.
Amin Tajgardoon is an Applied Scientist at the Amazon ML Solutions Lab. He has an extensive background in computer science and machine learning. In particular, Amin’s focus has been on deep learning and forecasting, prediction explanation methods, model drift detection, probabilistic generative models, and applications of AI in the healthcare domain.
Yash Shah is a Science Manager in the Amazon ML Solutions Lab. He and his team of applied scientists and machine learning engineers work on a range of machine learning use cases from healthcare, sports, automotive and manufacturing.
Vamshi Krishna Enabothala is a Sr. Applied AI Specialist Architect at AWS. He works with customers from different sectors to accelerate high-impact data, analytics, and machine learning initiatives. He is passionate about recommendation systems, NLP, and computer vision areas in AI and ML. Outside of work, Vamshi is an RC enthusiast, building RC equipment (planes, cars, and drones), and also enjoys gardening.
Greg Tolmie is an Account Manager on the AWS Public Sector ISV partners team. Greg supports a portfolio of AWS public sector ISV partners to help them grow and mature their adoption of AWS services while maximizing benefits of the AWS partner network.