{"blocks": [{"key": "6ccb0540", "text": "Scenario", "type": "header-two", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "ac8e52b7", "text": "WhatsApp is considering launching a group video-call feature; currently it does not exist.", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "3f93c30d", "text": "Question", "type": "header-two", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "0676025d", "text": "a) Using the available call-level data, outline how you would determine whether there is demand for group calls.", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "2ad44cf3", "text": "b) What additional quantitative and qualitative data would you request, and how would you analyze it?", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "e173c8c0", "text": "c) After launch, list success and guard-rail metrics; if you could keep only one success metric, which one and why?", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "440b5e11", "text": "d) Before launch, engineering asks for an experiment design—describe step-by-step how you would run and analyze the test, including randomization unit, clustering to reduce spill-over, novelty effects, and criteria for statistical & business significance.", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "c0287869", "text": "Hints", "type": "header-two", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}, {"key": "7cc2067e", "text": "Frame analysis: opportunity sizing → metric hierarchy → clustered A/B test design → interpretation of lift vs. risk.", "type": "unstyled", "depth": 0, "inlineStyleRanges": [], "entityRanges": [], "data": {}}], "entityMap": {}}