Alias for nse(). MEC, NSE, and the uppercase R-squared efficiency R2()
are the same statistic. They must not be confused with lowercase r2(),
the squared Pearson correlation.
Details
$$\mathrm{MEC}=1-\frac{\sum_{i=1}^{n}(obs_i-pred_i)^2} {\sum_{i=1}^{n}(obs_i-\bar{obs})^2}.$$
Its interpretation and references are given in nse(). It returns NA
with a warning under the same undefined conditions as nse().
Examples
mec(1:3, c(1, 3, 2))
#> [1] 0