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Transformer Encoder from Scratch

data science & mlAdvanced365d access
199onwards

Implement a full Transformer encoder — multi-head attention, positional encoding, layer norm — in PyTorch from scratch. Train on a classification task. No HuggingFace shortcuts.

  • Implement scaled dot-product attention and multi-head attention from scratch in PyTorch
  • Build sinusoidal positional encoding and understand why position matters in Transformers
  • Assemble a complete Transformer encoder block with residual connections and layer norm
  • Train an encoder classifier end-to-end on a real text classification dataset

Fine-tuning Data Preparation Pipeline

data science & mlAdvanced365d access
199onwards

Scrape content, clean it, auto-generate instruction-response pairs using an LLM, score quality with an evaluator model, and output a production-ready JSONL dataset.

  • Build an async web scraping pipeline using httpx and BeautifulSoup
  • Clean, deduplicate, and validate raw text content at scale
  • Auto-generate instruction-response training pairs using an LLM
  • Score dataset quality using an LLM judge and apply rule-based filters

Feature Store for ML Pipelines

data science & mlIntermediate365d access
149onwards

Build a lightweight feature store that computes, caches, and serves ML features. Connect it to both a training pipeline and a real-time prediction API.

  • Understand the purpose of a feature store and the training/serving skew problem
  • Compute, version, and store ML features in Redis (real-time) and PostgreSQL (historical)
  • Connect a feature store to both a training pipeline and a live inference API
  • Verify consistency between features used in training and features used in serving

Sentiment Classifier: LSTM vs. LLM

data science & mlIntermediate365d access
149onwards

Train an LSTM on real product reviews. Run the same data through a zero-shot LLM classifier. Compare accuracy, latency, and cost — understand where each belongs.

  • Build, train, and evaluate an LSTM text classifier in PyTorch
  • Implement a zero-shot LLM classifier and measure its performance
  • Compare trained models vs LLMs on accuracy, latency, and cost per prediction
  • Understand the trade-off space: when to use fine-tuned models vs zero-shot LLMs

LLM Output Evaluation Dataset Builder

data science & mlIntermediate365d access
149onwards

Generate a benchmark dataset by prompting an LLM across many scenarios, score outputs on multiple criteria, and produce a structured eval report with failure analysis.

  • Design a multi-dimensional scoring rubric for evaluating LLM outputs
  • Generate structured evaluation datasets using async LLM API calls
  • Build an LLM-as-judge pipeline that scores model responses automatically
  • Calculate inter-rater agreement between human and automated scoring

Sales Forecasting with Time Series

data science & mlBeginner365d access
99onwards

Forecast product sales using Prophet and ARIMA. Build a Streamlit dashboard that visualizes predictions vs. actuals and explains seasonality and trend components.

  • Identify trend, seasonality, and stationarity in a real time series dataset
  • Train and evaluate both Prophet and ARIMA forecasting models
  • Compare model performance using MAE, RMSE, and MAPE
  • Visualize forecast results with confidence intervals in Streamlit

Customer Churn Predictor with XGBoost

data science & mlBeginner365d access
99onwards

Train an XGBoost classifier on a real customer dataset, tune hyperparameters with cross-validation, and deploy it as a FastAPI prediction endpoint.

  • Perform end-to-end ML: EDA → feature engineering → model training → evaluation → deployment
  • Train and tune an XGBoost classifier with cross-validation
  • Handle class imbalance using scale_pos_weight
  • Evaluate a classifier using precision, recall, F1, and ROC-AUC

Data Labeling Pipeline for AI Training

data science & mlBeginner365d access
99onwards

Build a pipeline that presents raw text data for human labeling via a clean UI and exports a structured JSONL dataset ready for LLM fine-tuning.

  • Design a practical data labeling schema for a real NLP classification task
  • Build a human-in-the-loop labeling tool using Streamlit
  • Export labeled data in the JSONL instruction-tuning format
  • Validate dataset quality: check for empty fields, label imbalance, and duplicates

Movie Recommendation Engine

data science & mlFoundation365d access
99onwards

Build a content-based recommendation system using TF-IDF and cosine similarity. Enter a movie, get 5 similar recommendations. Intuition-builder for how embeddings work

  • Understand TF-IDF vectorization and cosine similarity intuitively
  • Build a content-based recommendation engine from scratch
  • Implement a nearest-neighbour search using cosine similarity matrices
  • Connect recommendation logic to an interactive Streamlit UI\

Student Score Predictor

data science & mlFoundation365d access
99onwards

Train a linear regression model to predict student exam scores from study hours, attendance, and test scores. Deploy it as a simple Streamlit app with a prediction form.

  • Build and train a linear regression model using scikit-learn
  • Encode categorical variables and prepare features for ML models
  • Evaluate regression models using RMSE and R² metrics
  • Save a trained model to disk and load it for inference

Exploratory Data Analysis Dashboard

data science & mlFoundation365d access
99onwards

Take a real-world dataset, clean it, explore distributions, correlations, and outliers, and visualize everything in a Streamlit dashboard. The foundation of all data work

  • Load and clean a real-world dataset using pandas
  • Identify and handle missing values, duplicates, and outliers
  • Visualize distributions and correlations using matplotlib and seaborn
  • Build an interactive multi-chart Streamlit dashboard
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