Bioequivalence and Bioavailability Forum • Outliers

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

posted by Helmut – Vienna, Austria, 2011-03-24 16:09 (5139 d 20:15 ago) – Posting: # 6806
Views: 38,286

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 . I have blocked some pages (i.e., the download section and the latest posts) from 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 .

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!
Helmut Schütz

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

Complete thread:

EMA BE-GL: Clarifications / Corrections? Helmut 2010-06-22 18:53 [BE/BA News]
- Good news!? d_labes 2010-06-23 10:09
  - Good news!? Helmut 2010-06-23 10:11
    - Update Helmut 2011-02-05 18:48
      - Q&A published 14 March 2011 Helmut 2011-03-16 13:44
        
        Q&A published 14 March 2011 ElMaestro 2011-03-16 14:20
        Phoenix/WinNonlin 6.1.0.173 Helmut 2011-03-17 04:23
        ANOVA party prevails d_labes 2011-03-17 11:00
        
        THX! Helmut 2011-03-19 02:59
        
        Outlier d_labes 2011-03-24 11:55
        
        Outliers - yes, but how?Helmut 2011-03-24 15:09
        
        Questions and Ambiguities d_labes 2011-03-28 14:16
        Residuals and Outliers in Replicate Design Crossover Studies d_labes 2011-04-04 08:53
        
        Info requested ElMag 2011-03-24 12:45
        
        Confused as well... Helmut 2011-03-24 16:50
        
        Q&A published 14 March 2011 Priyanka_S 2011-03-21 14:28
        
        SAS code: Warning d_labes 2011-03-21 16:08
        
        Copy & paste Helmut 2011-03-21 22:38
        
        Subtleties, flaws, questions d_labes 2011-03-22 09:24
        
        Subtleties, flaws, questions Helmut 2011-03-27 20:35
        
        Not estimable in the model The user 2017-03-14 10:16
        
        Not estimable in the model ElMaestro 2017-03-14 11:02
        
        Not estimable in the model The user 2017-03-14 12:13
        
        Not estimable in the model ElMaestro 2017-03-14 12:41
        
        Not estimable in the model Helmut 2017-03-18 21:59
        
        Food not the same between groups Beholder 2021-11-10 14:35
        
        Food not the same between groups ElMaestro 2021-11-17 09:50