# A concrete type I/III Sum of square problem

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## A concrete type I/III Sum of square problem

 Hi R-help members, I have read a lot in the Archive about the "Type I" vs "Type III" sum of square. I think I have read confusing post so I want to have a clear idea of the problem. Here is an example. I have 3 groups of subjects of unequal sample size (G1 (n=7), G2 (n=7), G3 (n=4)). for Each subject I have 4 measures corresponding to  the crossing of 2 factor  (A & B) of two levels each. my dependant variable is X. After reading a lot of tutorials on R I have tried the summary(aov(X~GROUP*A*B+Error(SUJECT/(A*B) ) This results are with "type I SS". What's wrong with these results ? Should I use type III SS and, if so how to enter my design in Anova (car package, I still have not the J.  Fox's book) ? I have clearly not understood the difference between type I & III (with the limits of each approach).  A link to a good tutorial on this topic will help me a lot. Sylvain CLEMENT "Neuropsychology & Auditory Cognition Team" Lille, FRANCE ______________________________________________ [hidden email] mailing list https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
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## Re: A concrete type I/III Sum of square problem

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## Re: A concrete type I/III Sum of square problem

 Thanks Brian for the reference.   I just discover that it is available in our library so I going to take it & read it soon. Actually, I don't even know the difference between a multistratum vs a single-stratum AOV. A quick search on google returned me the R materials so that I imagine that these concepts are quite specific to R. I will read the book first before asking for more informations. Thanks Sylvain Clément At 12:38 14/02/2006, you wrote: >More to the point, you are confusing >multistratum AOV with single-stratuam AOV.  For >a good tutorial, see MASS4 (bibliographic >information in the R FAQ).  For unbalanced data >we suggest you use lme() instead. > >-- >Brian D. Ripley,                  [hidden email] ______________________________________________ [hidden email] mailing list https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
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## Re: A concrete type I/III Sum of square problem

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## Re: A concrete type I/III Sum of square problem

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## Re: A concrete type I/III Sum of square problem

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## Re: A concrete type I/III Sum of square problem

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## Re: A concrete type I/III Sum of square problem

 On 16 Feb 2006 11:55:47 +0100, Peter Dalgaard <[hidden email]> wrote: > Gregor Gorjanc <[hidden email]> writes: > ... > > Can you (prof. Dalgaard) please point us to relevant book with these > > topics. I am very interested in it since my data are often unbalanced. > > Hmm, the Danish tradition is highly based on lecture notes, so I don't > have a specific book for you. One possible starting point is If there are some good lecture notes around I would like to read them even more ;) > Tue Tjur (1984): Analysis of variance designs in orthogonal designs. > Int.Statist.Review 52, 33-81. Thank you very much for this reference and example code! -- Lep pozdrav / With regards,     Gregor Gorjanc ---------------------------------------------------------------------------------------------------- University of Ljubljana          PhD student Biotechnical Faculty Zootechnical Department     URI: http://www.bfro.uni-lj.si/MR/ggorjanGroblje 3                            mail: gregor.gorjanc bfro.uni-lj.si SI-1230 Domzale                tel: +386 (0)1 72 17 861 Slovenia, Europe                 fax: +386 (0)1 72 17 888 ---------------------------------------------------------------------------------------------------- "One must learn by doing the thing; for though you think you know it,  you have no certainty until you try." Sophocles ~ 450 B.C. ______________________________________________ [hidden email] mailing list https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
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## Re: A concrete type I/III Sum of square problem

 Gregor GORJANC <[hidden email]> writes: > On 16 Feb 2006 11:55:47 +0100, Peter Dalgaard <[hidden email]> wrote: > > Gregor Gorjanc <[hidden email]> writes: > > > ... > > > Can you (prof. Dalgaard) please point us to relevant book with these > > > topics. I am very interested in it since my data are often unbalanced. > > > > Hmm, the Danish tradition is highly based on lecture notes, so I don't > > have a specific book for you. One possible starting point is > > If there are some good lecture notes around I would like to read them > even more ;) You may find that there is a language barrier....   > > Tue Tjur (1984): Analysis of variance designs in orthogonal designs. > > Int.Statist.Review 52, 33-81. > > Thank you very much for this reference and example code! --    O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B   c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K  (*) \(*) -- University of Copenhagen   Denmark          Ph:  (+45) 35327918 ~~~~~~~~~~ - ([hidden email])                  FAX: (+45) 35327907 ______________________________________________ [hidden email] mailing list https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
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## Re: A concrete type I/III Sum of square problem

 On 16 Feb 2006 13:30:31 +0100, Peter Dalgaard <[hidden email]> wrote: > Gregor GORJANC <[hidden email]> writes: > > > On 16 Feb 2006 11:55:47 +0100, Peter Dalgaard <[hidden email]> wrote: > > > Gregor Gorjanc <[hidden email]> writes: > > > > > ... > > > > Can you (prof. Dalgaard) please point us to relevant book with these > > > > topics. I am very interested in it since my data are often unbalanced. > > > > > > Hmm, the Danish tradition is highly based on lecture notes, so I don't > > > have a specific book for you. One possible starting point is > > > > If there are some good lecture notes around I would like to read them > > even more ;) > > You may find that there is a language barrier.... Oh, dear. I hoped for lecture notes written in universal language for stats. i.e. R, you probably heard about it. Just joking. Thanks anyway. -- Lep pozdrav / With regards,     Gregor Gorjanc ---------------------------------------------------------------------------------------------------- University of Ljubljana          PhD student Biotechnical Faculty Zootechnical Department     URI: http://www.bfro.uni-lj.si/MR/ggorjanGroblje 3                            mail: gregor.gorjanc bfro.uni-lj.si SI-1230 Domzale                tel: +386 (0)1 72 17 861 Slovenia, Europe                 fax: +386 (0)1 72 17 888 ---------------------------------------------------------------------------------------------------- "One must learn by doing the thing; for though you think you know it,  you have no certainty until you try." Sophocles ~ 450 B.C. ______________________________________________ [hidden email] mailing list https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide! http://www.R-project.org/posting-guide.html