From 618e56f160e2da6eb3ed9fa2e21807dd7b0b2efd Mon Sep 17 00:00:00 2001 From: Theophile GENTILHOMME <tgentilhomme@jurasix08.idiap.ch> Date: Thu, 22 Mar 2018 09:00:29 +0100 Subject: [PATCH] Add an example of conf interval in the guide --- doc/guide.rst | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/doc/guide.rst b/doc/guide.rst index 352f23a..fc7a849 100644 --- a/doc/guide.rst +++ b/doc/guide.rst @@ -226,8 +226,19 @@ and confidence value :math:`\alpha` is used as :py:func:`bob.measure.utils.confidence_for_indicator_variable`. It is based on the cumulative probabilities of the binomial distribution. This method is quite conservative, meaning that the true coverage rate of a 95% -Clopper–Pearson interval may be well above 95%. +Clopper–Pearson interval may be well above 95%. +For example, we want to evaluate the reliability of a system to +identify registered persons. Let's say that among 10,000 accepted +transactions, 9856 are true matches. The 95% confidence interval for true match +rate is then: +.. doctest:: python + + >>> bob.measure.utils.confidence_for_indicator_variable(9856, 10000) + (0.98306835053282549, 0.98784270928084694) + +meaning there is a 95% probability that the true match rate is inside :math:`[0.983, +0.988]`. Plotting -------- -- GitLab