Estimate the CSM effect at the $100k threshold properly

Causal inferenceHard

Problem. Accounts are supposed to get a dedicated customer success manager once their ARR passes $100,000. A quick comparison of accounts just above and below the line suggested about 4 points of extra net dollar retention. Some accounts below the line got a CSM anyway, and some above didn't. Do a proper regression discontinuity analysis: what do you estimate, and how do you check it?

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