Outliers - yes, but how? [BE/BA News]

posted by Helmut Homepage – Vienna, Austria, 2011-03-24 16:09 (4338 d 06:10 ago) – Posting: # 6806
Views: 32,647

Dear D. Labes!

❝ This quote, or is it your own poetry, …


I borrowed it from a personal discussion page at Wikipedia.

❝ … is really google resistant. First time that I noticed the Net is not omniscient!


Well, personal discussion pages of WP are blocked from being indexed by [image]. I have blocked some pages (i.e., the download section and the latest posts) from [image] as well. Requires two lines in the domain’s robots.txt
User-agent: *
Disallow: /foo/

… and adding rel="nofollow" to respective links within other pages (the same is done here; look at the HTML code).

❝ ❝ … Did you have a look at box plots and/or QQ-plots of residuals? What about subjects 45 and 52 (studentized residuals outside ±1.96 and outside 3×IQR)?


❝ Which residuals did you analyse? Which model? Please enlighten me.


I used EMA’s crippled model (test removed), Sequence+Subject(Sequence)+Period and threw away one period’s residuals (same values, but different in signs to the respective other one).

❝ What do you think: which type of boxplot should we apply? Best for our sponsors would be a simple boxplot with whiskers up to minimum/maximum not showing any 'outlier' :-D.


:rotfl:

I have chosen ±3×IQR following the convention (!) that values within 1.5-3×IQR are ‘mild’ outliers and outside 3×IQR are ‘severe’ outliers. I’m exploring full replicate data-sets right now – outliers almost in all of them. Don’t know whether residuals make any sense at all (see also this post: period ratios instead?). I would end up with different numbers of outliers, depending on the method of calculation of the IQR (see R-manual). Period ratios (second / first administration):
Type 3: SAS according to R-doc - 2 outliers (#46: 3.524, #45: 26.08)
Type 5: or is this SAS? - 2 outliers
Type 6: Minitab, SPSS, Phoenix/WinNonlin - 2 outliers
Type 7: default in S, R - 3 outliers (as above + #13: 3.349)

                               CVWR    Scaled  AR      width
Full data set:                 47.0  71.23 - 140.40    69.17
#45, #52 excluded (residuals): 32.2  78.79 - 126.93    48.14
#45, #46 excluded (ratios):    35.3  77.08 - 129.73    52.65


Don’t know what to do. :confused: Suggestions?
Maybe Q&A is an abbreviation for Questions and Ambiguities.

Dif-tor heh smusma 🖖🏼 Довге життя Україна! [image]
Helmut Schütz
[image]

The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes

Complete thread:

UA Flag
Activity
 Admin contact
22,485 posts in 4,710 threads, 1,603 registered users;
19 visitors (0 registered, 19 guests [including 10 identified bots]).
Forum time: 22:19 CET (Europe/Vienna)

The difference between a surrogate and a true endpoint
is like the difference between a cheque and cash.
You can get the cheque earlier but then,
of course, it might bounce.    Stephen Senn

The Bioequivalence and Bioavailability Forum is hosted by
BEBAC Ing. Helmut Schütz
HTML5