title: How to run Dunnett C post hoc test in R?
body: <p>I ran a two-way anova in r with my data set (unequal sample sizes, unequal variance): 1 variable measured across 3 species (with males and females in each species).
  This produces a significant result between species, so I want to know which pairwise comparisons produce the significance. I know that there are functions in packages for performing post hoc tests in R:
  e.g.</p>
  
  <p>Dunnett's post hoc test from <a href="http://www.uwlax.edu/faculty/toribio/math305_fall09/multiple.txt" rel="nofollow">http://www.uwlax.edu/faculty/toribio/math305_fall09/multiple.txt</a>.
  Packages required: "multcomp", "mvtnorm", "survival", "splines"</p>
  
  <pre><code>library(multcomp)           
  test.dunnett=glht(anova_results,linfct=mcp(method="Dunnett"))
  confint(test.dunnett)
  plot(test.dunnett)
  </code></pre>
  
  <p>*note: glht is described in "multcomp"</p>
  
  <p>But Dunett's test is designed to compare all groups to a control. Instead I want to compare all groups to each other, the Dunnett C. 
  Does anyone know of a package that performs Dunnett C or knows how to code it? (equation at: <a href="http://pic.dhe.ibm.com/infocenter/spssstat/v21r0m0/index.jsp?topic=%2Fcom.ibm.spss.statistics.help%2Falg_posthoc_unequalvar.htm" rel="nofollow">http://pic.dhe.ibm.com/infocenter/spssstat/v21r0m0/index.jsp?topic=%2Fcom.ibm.spss.statistics.help%2Falg_posthoc_unequalvar.htm</a>)</p>