Water Absortion in Wheat Flour

Undertand you product and the parameters of that product it is very important for the development of the calibration. XY Plots and Residuals plot helps to understand them you use colors, symbols or other resources to create them.

In this case is a validation of water absortion in wheat flour, and all the samples are represented (low, medium and high strength (Flojas, Media Fuerza y Fuerza) , and  some use aditives and others not. 

Filters and other functions of ggplot or R, help to see the figures in more details and get interesting information to improve the calibration.