4.2) ANOVA

A common problem in geology when compiling datasets is that elements have been determined
by a variety of techniques and on different instruments. It is therefore of crucial importance to verify
that such datasets are not biased. This is generally achieved by analyzing inter-laboratory standards
followed by a test to determine whether the results are significantly different or not.

Here, to test intra-laboratory reproducibility, 6 sediment reference materials have been analyzed for 
their Sr content using three techniques. 

Is there a significant difference in Sr content between the various techniques at alpha = 5%? 
And what about the difference between samples?
If there is a difference between techniques, level the data to the AES method.

Data: 
            sample     AES      ES        AAS
                 1          0.96     0.94      0.98
                 2          0.96     0.98      1.01
                 3          0.85     0.87      0.86
                 4          0.86     0.84      0.90
                 5          0.86     0.87      0.89
                 6          0.89     0.93      0.92