In my assignment, I have a table showing chemical analyses of water in two separate years. I am trying to test if there is a significant difference in concentrations of major ions between the two years.
For example, to keep it sample. I want to compare if sodium concentrations are different in year 2016, compared to year 2017. The sample sizes are not the same (n > 30 for each) and they are not normally distributed data. Therefore, I used Mann Whitney Wilcoxon to test for differences in R.
I get a p-value, and I understand what the two possible outcomes are. Let's say that in my specific case, I get a p-value of 0.0003 at alpha = 0.05, indicating that there is a significant change. But I don't really know how to report this in-text (in my interpretation). This is what I have right now.
"Statistical analyses showed that sodium concentrations in 2016 were significantly different from those in 2017 (P < 0.05) " Is this a correct interpretation? Any help is appreciated! Thanks.