dorsal/arxiv
View SchemaA note on Delta ln L = -1/2 Errors
| Authors | Roger Barlow |
|---|---|
| Categories | |
| ArXiv ID | physics/0403046 |
| URL | https://arxiv.org/abs/physics/0403046 |
Abstract
The points at which the log likelihood falls by 1/2 from its maximum value are often used to give the `errors' on a result, i.e. the 68% central confidence interval. The validity of this is examined for two simple cases: a lifetime measurement and a Poisson measurement. Results are compared with the exact Neyman construction and with the simple Bartlett approximation. It is shown that the accuracy of the log likelihood method is poor, and the Bartlett construction explains why it is flawed.
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"abstract": "The points at which the log likelihood falls by 1/2 from its maximum value\nare often used to give the `errors\u0027 on a result, i.e. the 68% central\nconfidence interval. The validity of this is examined for two simple cases: a\nlifetime measurement and a Poisson measurement. Results are compared with the\nexact Neyman construction and with the simple Bartlett approximation. It is\nshown that the accuracy of the log likelihood method is poor, and the Bartlett\nconstruction explains why it is flawed.",
"arxiv_id": "physics/0403046",
"authors": [
"Roger Barlow"
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"physics.data-an",
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"title": "A note on Delta ln L = -1/2 Errors",
"url": "https://arxiv.org/abs/physics/0403046"
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