Joyston Menezes
Hey there, I’m

M.S. in Computer Science (USC) · Research Assistant, UCLA Department of Communication · Studying health misinformation, algorithmic exposure, and how we measure them.

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Health Communication, Misinformation & Measurement

I study how people encounter health information on algorithmic platforms, and how we can measure that exposure reliably. Trained in computer science at USC, I now work in UCLA's Department of Communication (OASIS Lab), where I build and evaluate LLM pipelines for health misinformation. I also collaborate with Prof. Magdalena Wojcieszak's team at UC Davis and the University of Warsaw on news exposure, and at USC ISI I built the data pipelines behind a public dataset of the 2024 U.S. election on TikTok.

Across these projects I keep returning to one question: what do our classifiers, topic models, and LLM judges actually measure, and who do they miss?

Education

Jan 2023 – Dec 2024

Master of Science in Computer Science

University of Southern California, Viterbi School of Engineering | Los Angeles, CA

GPA: 3.71/4.00  ·  Coursework: Applied Natural Language Processing, Information Retrieval and Web Search Engines, Database Systems, Analysis of Algorithms, Web Technologies, Multimedia Systems Design.

The Order of the Laurel and the Palm (2025)

USC's highest honor for graduating students, recognizing leadership, scholarship, and service.

Aug 2017 – Aug 2021

Bachelor of Engineering in Computer Science

NMAM Institute of Technology | Nitte, India

Thesis: Detection and Visualization of Bone Abnormalities on X-ray Images Using Convolutional Neural Networks (Best Project of the University, 2021).
Leadership: Student President; Branch Captain for the Computer Science Department.

Best Outgoing Student & Outstanding Achievement Award (2021)

Best Outgoing Student of the College and of the Computer Science Department.

Experience

Research

Aug 2026 – Present Research Collaborator | UC Davis Department of Communication & University of Warsaw PI: Prof. Magdalena Wojcieszak · Remote
  • Audit feasibility: Assessed the feasibility of cross-platform sockpuppet audits of recommendation, search, and AI search features across nine platforms, informing the team's audit planning.
  • Celebrity mentions at scale: Matched celebrity mentions across 29,999,224 Facebook news posts (1,112,649 matched), reducing the team's political-classifier workload 27-fold; identified 94,349 duplicate records.
  • Measurement validation: Fit a BERTopic model on a GPU cluster and validated it with a web-based word-intrusion test: coders identified the intruder 93.5% of the time, with 86–92% inter-coder agreement. Built an outlet typology and per-celebrity concentration measures.
Feb 2026 – Present Research Assistant | OASIS Lab, Department of Communication, UCLA Advisors: Prof. Homa Hosseinmardi and Prof. Amir Ghasemian
  • Health misinformation on TikTok: Built an LLM classification pipeline (Python, GPT-4o-mini) using zero-shot structured outputs to enforce a six-dimension annotation taxonomy, and analyzed the distribution of high-risk medical claims.
  • Evaluating AI replies to cancer misinformation: Implemented eight evaluation metrics comparing Gemini-generated and Reddit community replies (12,663 responses, 380 posts), showing that a single empathy score hid a split between expressed warmth and demonstrated understanding.
  • Acknowledged contribution to a cancer-misinformation taxonomy study published in Findings of EMNLP 2026.
  • Children's YouTube census: 103,066 videos from channels with more than one million subscribers, verified against reported upload counts, with metadata, a 17,517-video stratified sample, and transcripts.
Aug 2024 – Jan 2026 Research Assistant | HUMANS Lab, USC Information Sciences Institute Supervisors: Prof. Luca Luceri and Prof. Emilio Ferrara
  • 2024 U.S. election on TikTok: Built scraping and preprocessing pipelines (Python, Pandas, Apache Spark) covering 1M+ TikTok and X posts and 10M+ comments, contributing to a public dataset of 3.14 million TikTok videos (WWW '25 Companion).
  • Topic modeling: Consolidated 700+ fragmented BERTopic topics into 10 coherent themes, with VADER sentiment and engagement analysis.
Aug 2024 – May 2025 Research Assistant | Lerman Lab, USC Information Sciences Institute Supervisor: Prof. Kristina Lerman
  • Digital mental health ("Bigorexia"): Co-developed a hierarchical taxonomy distinguishing harmful from recovery-oriented muscle dysmorphia content, and helped build LLaMA- and Gemini-based classifiers to apply it to TikTok at scale (92% precision).
  • Led collection and preprocessing of TikTok and cross-platform data, with sentiment-aware topic modeling and multimodal embeddings to characterize how harm and recovery narratives co-occur.
Jun 2020 – Jul 2021 Research Assistant | NMAM Institute of Technology
  • Classified six common paddy crop diseases from leaf images with ML models and Spark-based Fuzzy C-Means segmentation; published as a CRC Press book chapter.
Aug 2023 – May 2024 Graduate Course Producer | CSCI 585 Database Systems, USC Prof. Saty Raghavachary
  • Supported 600+ students over two semesters: office hours, course materials, and help with assignments on data modeling, SQL, NoSQL, and MapReduce.
Jan 2023 – Present

Software Developer

Center for Homelessness, Housing, and Health Equity Research, USC

  • Developed five Android applications for field data collection, including the DemoGraphic Count app supporting the Greater Los Angeles Homeless Count.
  • Built, hosted, and maintained websites for the Center's projects (an Olympics homelessness site, Housing LA, and the Homeless Count site), averaging 12,000 to 15,000 visitors per week.
  • Produced GIS and spatial visualizations of homelessness patterns (ArcGIS, GeoJSON) and automated data ingestion with Python.
Aug 2021 – Nov 2022

Website Developer & Maintenance Engineer

Alphonso Consultancy | Udupi, India

  • Built responsive interfaces (Angular, JavaScript) with SQL and PHP back ends, improving operational efficiency by 40%.
Jan 2020 – Aug 2020

Project Lead & Intern

Quality Theorem | Bangalore, India

  • Led development of an online examination platform (Node.js, MongoDB, REST APIs, Docker).

Publications & Patents

Research & Development

Augmenting LLMs

Integrated DRAGON with LLaMA-7b-Chat

  • Integrated DRAGON (Dense Retriever) with LLaMA-7b-Chat to reduce hallucinations in large language models.
  • Employed dense retrieval techniques to ground model responses in accurate evidence from datasets like TriviaQA.
  • Achieved up to 59% improvement in answer accuracy compared to baseline generation.
  • View Project Document
Medical Imaging

Brain Tumor Detection from MRI Images

  • Developed a CNN model for early detection of brain tumors from MRI scans.
  • Implemented robust training pipelines to ensure high sensitivity and specificity in automated diagnostics.
  • Achieved 89% test accuracy on held-out MRI data.
Computer Vision

Deep Learning Photo Caption Generator

  • Created a system using VGG-16 for visual feature extraction and LSTM for sequence prediction.
  • Engineered the encoder-decoder architecture to translate visual semantics into natural language descriptions.
  • Generated descriptive image captions with high BLEU scores across benchmark datasets.
  • View Project Document
ML Honors

Detection & Visualization of Bone Abnormalities

  • Executed an ML project using TensorFlow and CNN to identify irregularities on X-ray images.
  • Implemented heatmaps and visualization tools to assist clinical professionals in abnormality identification.
  • The Project was honored as the top in the department and received university funding for further exploration.
  • View Project Document
NLP & Analytics

Aspect-Based Sentiment Analysis

  • Built a granular sentiment analysis engine to extract specific product features (aspects) from mobile reviews.
  • Utilized NLTK and Scikit-learn to classify sentiments per feature, enabling detailed consumer feedback loops.
  • View Project Analysis

Leadership & Involvement

2023 – Present

Team Lead | Greater Los Angeles Homeless Count

Led the DemoGraphic Count initiative, coordinating large-scale data collection efforts across Los Angeles to support regional housing and health equity research.

2017 – 2021

NSS | Better India Mission

Implemented waste management solutions in villages and launched the 'Piggy Bank' project to support homeless individuals and people living with HIV.

Feb 2020

Lead Organizer | HackRidea

Orchestrated a 24-hour National Level Hackathon. Managed logistics for 50+ teams and coordinated industry panels.

Grassroots Initiative

Paddy Crop Cultivation Drive | Belman, India

2019 – 2022: Revived a paddy field left barren for 15 years, cultivating it across consecutive seasons and donating the entire harvest to homeless and underprivileged families.

Elected Leadership

Vice President | ICYM, Udupi Diocese

2018 – 2022: Elected Vice President of the Indian Catholic Youth Movement for the Udupi Diocese, and served as Public Relations Officer of the state central council, leading youth-empowerment and social-welfare programs.

Humanitarian Trip

Tijuana, Mexico

November 2024: Collaborated with Esperanza to build houses for homeless people, providing hands-on construction and community support.

Humanitarian Trip

Colombia

March 2024: Engaged with indigenous Wayuu communities; assisted in building their first sustainable water tank for the village.

Skills & Technologies

AI & Data Intelligence

Large Language Models (LLM)TensorFlowPyTorchKerasScikit-learnOpenCVHugging FaceNLTKMachine Learning AlgorithmsApache SparkData Structures & Algorithms

Engineering & Databases

PythonJava (Core)C/C++JavaScriptTypeScriptNode.jsABAPHTML5CSS3SQLNoSQLMongoDBPostgreSQLFirebaseCockroachDB

Infrastructure, Cloud & Tools

AWSAzureGoogle Cloud Platform (GCP)DockerKubernetesJenkinsGitUNIXSAPREST APIsMicroservicesArcGISSwifterBootstrapRender

Honors & Awards

National Overseas Scholarship

Awarded by the Karnataka State Government to support distinguished postgraduate research abroad (April 2024).

Representative of India

Represented the nation at the Asian Level YCS Conference in Indonesia (July 2019).

Top Data Collector

USC Suzanne Dworak-Peck School of Social Work (May 2023).

Best Project of University

Undergraduate thesis on bone-abnormality detection, NMAM Institute of Technology (March 2021).

Best Outgoing Student

Honored at both the College and CS Department level (April 2021).

Sakura Science Exchange

Selected by Japan Science & Technology Agency for research at Ritsumeikan University (2020).

Outstanding Achievement Award

Highest recognition for holistic excellence, academic rigor, and leadership at NMAMIT (April 2021).

Beyond Research

Photography

First place at a national techno-cultural fest and third at Nitte Pixel. Years spent behind the lens before the research career.

View gallery

Football

Won Under-17 tournaments across the Udupi, Chikmagalur, and Mangalore districts of Karnataka, representing taluk and district teams.

Music & Design

Musician and graphic designer, with creative instincts that sneak into data visualizations (and the occasional website easter egg).