~/talk

Learning The Hows and Whys of Machine Learning

Talkat PHP UK Conference 2019 · 2019-02-20..02-22· [machine-learning, python]
slides:none on file

Tebex uses a data set of 18 million payments and iterates: a naive Bayes prototype fails on highly imbalanced data (2.8M good vs ~24k chargebacks), so experiments add resampling, tokenized binary features and move to naive Bayes then k‑NN via the PHP‑ML library. Per‑store models hit ~70% accuracy; per‑customer anomaly detection flags legitimate payments at ~85% (15% false positives) while catching ~31% of chargebacks. The team builds a prototype long‑running decision API and plans weighting, outlier removal and distance‑weighted k‑NN.

AI-written summary · about

  1. 0:00Start
  2. 7:15The Challenge
  3. 8:30Supervised Learning
  4. 9:55Classification
  5. 36:28Non-Sequential Data
  6. 49:04Per-Customer Detection
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