Compare clustering methods: k-means, hierarchical, DBSCAN, and GMM.
k-means is the reflex answer, yet it silently assumes round, equal-size clusters and requires you to know k in advance. What earns credit is positioning each alternative by the specific assumption it drops, and knowing when to use it.
Updated Sep 2026 · Grounded in real GenAI, LLM, and AI/ML engineering interview loops and written to a senior-engineer editorial bar.
k-means is the reflex answer, yet it silently assumes round, equal-size clusters and requires you to know k in advance. What earns credit is positioning each alternative by the specific assumption it drops, and knowing when to use it.
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.