How can we analyse the data from the following trial? Replication: None, Factors: Two (Dates, Genotypes) 1. Date of planting : 52 per year (every Wednesday) 2. Genotypes : 4 Total treatments: 52x4=208? Testing period*: 2 years (Y1 and Y2)
If you are going to do an ANOVA, you have to have some kind of replication.
It sounds like you have 52 x 4 x 2 years = 416 observations.
So the practical question is, Which observations will you group together as one treatment?
But the most important question is, What are you trying to find out? The answer to that question will guide how to proceed.
For example, I _suspect_ you want to know how each of these varieties perform when planted on different dates. In that case, each of the two years is a replication. You can do an anova that way, with 208 treatments, and two replications each. But that probably won't work out statistically, especially if the weather was at all different between the years.
Is there any way to condense the planting dates? For example, group all those in a certain month?
Also, if you are not trying to compare the two varieties to one another, it is okay to consider them as different experiments, unless including both helps you to understand the answer to the question you are asking.
But, really, you may not want to use anova. Perhaps plotting the [dependent variable] for each variety across all planting dates --- with error bars associated with the standard error across the years --- will tell you the information you are interested in?
Dear Salvatore
Greetings
Many thanks indeed for your prompt response with suggestions. From now onward, we will try to replicate it at least thrice during planting. However, now we will proceed as suggested by you.
Dear Tika
The principle assumption for ANOVA is the replication , in your case I think you can use year as block ( Randomized Complete Block Design ) if you have observation for treatment in each year .So block mean replication .
Good Luck
Dear Dr. Khalid
Many thanks indeed. To consider year as rep, we have tested the same genotype for two years only. Again, difficult to analyse it. So, from now onward we will test for one more year. i.e 3 years.
Best
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