HI All: Can anyone give me the formulae/steps for calculating the type III sum of squares for an unbalanced 2-way ANOVA design? Eg. we are looking at 8 treatments x 4 doses, with unequal numbers of replications within the groups. I really need the stepwise calculation, as I would try to put it in my own code (possibly in Visual Basic) to automate the task. Thanks very much. Karth.

Hope this helps. -michael calculating type III SS Use Anova(lm, type = "III") in the "car" package C:\Program Files\R\rw1031\library\car\html\Anova.html (below is from Brian D. Ripley) Yes, but we don't tell you how to avoid leading you into a mire. See http://www.stats.ox.ac.uk/pub/MASS3/Exegeses.pdf. Most of the time drop1() does what people are using `Type III' for. (C:\Program Files\R\rw1031\library\base\html\add1.html) -----Original Message----- From: Subramanian Karthikeyan [mailto:Subramanian_Karthikeyan@hc- sc.gc.ca] Sent: Tuesday, October 21, 2003 8:09 AM To: bioconductor@stat.math.ethz.ch Subject: [BioC] Type III Sum of Squares Calculation HI All: Can anyone give me the formulae/steps for calculating the type III sum of squares for an unbalanced 2-way ANOVA design? Eg. we are looking at 8 treatments x 4 doses, with unequal numbers of replications within the groups. I really need the stepwise calculation, as I would try to put it in my own code (possibly in Visual Basic) to automate the task. Thanks very much. Karth. LEGAL NOTICE\ Unless expressly stated otherwise, this messag...{{dropped}}

Thanks Mike, Is there a way of automating the task (e.g. using Perl or within R itself, maybe using a loop or something like that, so that I can I do a high-throughput analysis of several datasets, and then output/export the result tables in an excel spreadsheet? Any hint would be useful. Thanks again, Karth. "Man, Michael" <michael.man@pfiz to:="" "'subramanian="" karthikeyan'"="" <subramanian_karthikeyan@hc-sc.gc.ca="">, er.com> bioconductor@stat.math.ethz.ch cc: 2003-10-22 08:30 Subject: RE: [BioC] Type III Sum of Squares Calculation AM Hope this helps. -michael calculating type III SS Use Anova(lm, type = "III") in the "car" package C:\Program Files\R\rw1031\library\car\html\Anova.html (below is from Brian D. Ripley) Yes, but we don't tell you how to avoid leading you into a mire. See http://www.stats.ox.ac.uk/pub/MASS3/Exegeses.pdf. Most of the time drop1() does what people are using `Type III' for. (C:\Program Files\R\rw1031\library\base\html\add1.html) -----Original Message----- From: Subramanian Karthikeyan [mailto:Subramanian_Karthikeyan@hc-sc.gc.ca] Sent: Tuesday, October 21, 2003 8:09 AM To: bioconductor@stat.math.ethz.ch Subject: [BioC] Type III Sum of Squares Calculation HI All: Can anyone give me the formulae/steps for calculating the type III sum of squares for an unbalanced 2-way ANOVA design? Eg. we are looking at 8 treatments x 4 doses, with unequal numbers of replications within the groups. I really need the stepwise calculation, as I would try to put it in my own code (possibly in Visual Basic) to automate the task. Thanks very much. Karth. LEGAL NOTICE\ Unless expressly stated otherwise, this messag...{{dropped}}

Yes, you can use either Perl or R to do automate the task. The key is to get your data in the right format. Use apply() when you need do large number of loops because it will save the computing time. You may want to try library(RODBC) for DB connectivity. Michael -----Original Message----- From: Subramanian Karthikeyan [mailto:Subramanian_Karthikeyan@hc- sc.gc.ca] Sent: Wednesday, October 22, 2003 12:08 PM To: Man, Michael Cc: bioconductor@stat.math.ethz.ch Subject: RE: [BioC] Type III Sum of Squares Calculation Thanks Mike, Is there a way of automating the task (e.g. using Perl or within R itself, maybe using a loop or something like that, so that I can I do a high-throughput analysis of several datasets, and then output/export the result tables in an excel spreadsheet? Any hint would be useful. Thanks again, Karth. "Man, Michael" <michael.man@pfiz to:="" "'subramanian="" karthikeyan'"="" <subramanian_karthikeyan@hc-sc.gc.ca="">, er.com> bioconductor@stat.math.ethz.ch cc: 2003-10-22 08:30 Subject: RE: [BioC] Type III Sum of Squares Calculation AM Hope this helps. -michael calculating type III SS Use Anova(lm, type = "III") in the "car" package C:\Program Files\R\rw1031\library\car\html\Anova.html (below is from Brian D. Ripley) Yes, but we don't tell you how to avoid leading you into a mire. See http://www.stats.ox.ac.uk/pub/MASS3/Exegeses.pdf. Most of the time drop1() does what people are using `Type III' for. (C:\Program Files\R\rw1031\library\base\html\add1.html) -----Original Message----- From: Subramanian Karthikeyan [mailto:Subramanian_Karthikeyan@hc-sc.gc.ca] Sent: Tuesday, October 21, 2003 8:09 AM To: bioconductor@stat.math.ethz.ch Subject: [BioC] Type III Sum of Squares Calculation HI All: Can anyone give me the formulae/steps for calculating the type III sum of squares for an unbalanced 2-way ANOVA design? Eg. we are looking at 8 treatments x 4 doses, with unequal numbers of replications within the groups. I really need the stepwise calculation, as I would try to put it in my own code (possibly in Visual Basic) to automate the task. Thanks very much. Karth. LEGAL NOTICE\ Unless expressly stated otherwise, this messag...{{dropped}}