Sand, silt and clay compositions of 39 sediment samples of different water depth in an Arctic lake.
data(ArcticLake)Sand, silt and clay compositions of 39 sediment samples at different water depth (in meters) in an Arctic lake. The additional feature is a concomitant variable or covariate, water depth, which may account for some of the variation in the compositions. In statistical terminology we have a multivariate regression problem with sediment composition as regressand and water depth as regressor.
All row percentage sums to 100, except for rounding errors.
Aitchison: The Statistical Analysis of Compositional Data, 1986, Data 5, pp5.