Compare dimensionality reduction methods: PCA vs t-SNE vs UMAP.
These three get lumped together, yet they answer different questions: one is a preprocessing tool, two are eyeballing tools. The candidates who pass know precisely which structure each keeps and which it silently discards.
Updated Sep 2026 · Grounded in real GenAI, LLM, and AI/ML engineering interview loops and written to a senior-engineer editorial bar.
These three get lumped together, yet they answer different questions: one is a preprocessing tool, two are eyeballing tools. The candidates who pass know precisely which structure each keeps and which it silently discards.
Lead with where the obvious approach breaks, because that is the judgment they are screening for — most candidates jump straight to the happy path and lose the room.
Then walk the failure back through the pipeline in order, naming the one metric the customer's exec sponsor actually cares about before you propose the fix.
