R-help: I'm looking into the abundance of an algal species over site and years using a two-way ANOVA:> summary (aov (fserratus ~ site+year))Df Sum Sq Mean Sq F value Pr(>F) site 1 1487 1486.6 6.094 0.0155 * year 1 1173 1172.8 4.808 0.0309 * But I'm receiving the following warning messages when I run the Tukey test.> TukeyHSD(aov(fserratus ~ site+year))$site diff lwr upr p adj 1-0 -8.039565 -14.51045 -1.568685 0.0154723 Warning messages: 1: In replications(paste("~", xx), data = mf) : non-factors ignored: year 2: In TukeyHSD.aov(aov(fserratus ~ site + year)) : 'which' specified some non-factors which will be dropped Any advice would be appreciated, thanks. [[alternative HTML version deleted]]
I think you forgot to turn site and year into factors. (The 1 Df is the giveaway). -pd> On 15 May 2017, at 19:40 , Lucy McMahon <lucymcmahon004 at hotmail.co.uk> wrote: > > R-help: > > I'm looking into the abundance of an algal species over site and years using a two-way ANOVA: > >> summary (aov (fserratus ~ site+year)) > Df Sum Sq Mean Sq F value Pr(>F) > site 1 1487 1486.6 6.094 0.0155 * > year 1 1173 1172.8 4.808 0.0309 * > > But I'm receiving the following warning messages when I run the Tukey test. >> TukeyHSD(aov(fserratus ~ site+year)) > > $site > diff lwr upr p adj > 1-0 -8.039565 -14.51045 -1.568685 0.0154723 > > Warning messages: > 1: In replications(paste("~", xx), data = mf) : non-factors ignored: year > 2: In TukeyHSD.aov(aov(fserratus ~ site + year)) : > 'which' specified some non-factors which will be dropped > > > Any advice would be appreciated, thanks. > > > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.-- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Office: A 4.23 Email: pd.mes at cbs.dk Priv: PDalgd at gmail.com
you have only one df for site and one df for year. most likely you skipped the step of telling R those are factors. On Mon, May 15, 2017 at 1:40 PM, Lucy McMahon <lucymcmahon004 at hotmail.co.uk> wrote:> R-help: > > I'm looking into the abundance of an algal species over site and years using a two-way ANOVA: > >> summary (aov (fserratus ~ site+year)) > Df Sum Sq Mean Sq F value Pr(>F) > site 1 1487 1486.6 6.094 0.0155 * > year 1 1173 1172.8 4.808 0.0309 * > > But I'm receiving the following warning messages when I run the Tukey test. >> TukeyHSD(aov(fserratus ~ site+year)) > > $site > diff lwr upr p adj > 1-0 -8.039565 -14.51045 -1.568685 0.0154723 > > Warning messages: > 1: In replications(paste("~", xx), data = mf) : non-factors ignored: year > 2: In TukeyHSD.aov(aov(fserratus ~ site + year)) : > 'which' specified some non-factors which will be dropped > > > Any advice would be appreciated, thanks. > > > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.