I want to check whether there is a difference between three treatment groups with the help of a One-way ANOVA.
The values I have for each treatment group are means with standard deviation. Even though I know the values from which the means are calculated, they are repeated measures of the same sample, and I want to use the means of three independent samples to check the difference between the groups.
My dataset is pretty simple however I can't seem to find a solution to let R (statistical program I use) know that the value I have for each sample within a group resembles a mean with standard deviation. I know that an ANOVA takes the average of all the samples within a group and then compares the means between the groups to see for differences between groups but surely when your values for each sample are already means then this will certainly have an effect, right?
Intuitively I feel that this effects the outcome of my analysis, or is my intuition miles off...?
Thanks in advance!!
My suggestion is to add the raw data in and do a two-way ANOVA. One predictor is Treatment and the other is Sample. Then you can just use the anova function from R. This tutorial may help you in using the anova function for a two-way ANOVA.