From sokol at insa-toulouse.fr  Tue May 30 16:01:17 2017
From: sokol at insa-toulouse.fr (Serguei Sokol)
Date: Tue, 30 May 2017 16:01:17 +0200
Subject: [Rd] stats::line() does not produce correct Tukey line when n
 mod 6 is 2 or 3
In-Reply-To: <22829.8246.695545.320438@stat.math.ethz.ch>
References: <CAN7_cLjefc605D1ATS__MOV4gN7fKDBo5Nx_CNB_B9cDbAxc6w@mail.gmail.com>
 <ffc3e473-622d-796f-a06a-6e1f92f8ab5f@gmail.com>
 <CAN7_cLjmQFtZf9z-qJKdWRCaRY2uxfP8k5=QJsptz3U+TtP8oA@mail.gmail.com>
 <CAN7_cLjbz6S8u79jtx52XgfD1LcpO8CePYUhrunYqrzXHMMN8A@mail.gmail.com>
 <024A7E7D-45F8-4C95-A9BD-DBEB1D085BFA@gmail.com>
 <94b65a5b-da9e-ec5c-e428-7c5dbf175ec1@insa-toulouse.fr>
 <8c167bbb-130d-3798-a9e8-24c4377db313@insa-toulouse.fr>
 <d10ebb8c-0c49-5b0e-5b3c-b06073bfe447@insa-toulouse.fr>
 <22829.8246.695545.320438@stat.math.ethz.ch>
Message-ID: <396781eb-1712-aa54-96f2-a6c4df0284f4@insa-toulouse.fr>

Le 30/05/2017 ? 09:33, Martin Maechler a ?crit :
...
> However, even after the patch,
> The example from the SO post differs from the result of Richie
> Cotton's function...
The explanation is quite simple. In SO function, the first 1/3 quantile
of used example counts 6 points (of 19 in total), while line()'s
definition of quantile leads to 8 points. The same numbers
(6 and 8) are on the other end of sample. In x sample, there are
few repeated values, this is certainly be the reason of different quantiles..

I am not sure that one quantile definition is better or more correct
than the other. So I would leave line()'s definition as is.

Best,
Sergue?.



[Rd] stats::line() does not produce correct Tukey line when n mod 6 is 2 or 3
Serguei Sokol