The European Union is restricting variable pay to a maximum of two-and-a-half times base salaries.
The variables RACING SHOD and MEDICAL TREATMENTS are restricted variables for which only the qualified horses and injured horses, respectively, were categorised.
Other proteomic and genetic human wide population studies have highlighted the need to restrict variables in sample sets, such as, genetic, gender, and age background, in order to achieve interpretable results.
Due to the limited number of events, we restricted variable inclusion in the model [ 26].
For graphical representations, the variable (pathways) plot and the individual (genomes) plot were combined, restricting plotted variables to those with a quality of representation greater than 0.75, in order to conserve interpretability.
Extending qualitative CSPs with the ability of restricting selected variables to finite sets of possible values has been proposed as an interesting research direction with important applications, cf. "Qualitative constraint satisfaction problems: an extended framework with landmarks" by Li, Liu, and Wang (2013) [48].
Votruba et al. [ 24] formulated a model of the fermentation process for batch cultures without including the intermediate metabolites, restricting the variables to biomass, glucose and the end products and this model captures well the two phases.
This variable selection method limits the discovery capability of the method, however, and the methods described below try to strike a more even balance between guiding the results via the use of covariates of general relevance without restricting the variables to the point of no longer allowing the data to drive the endotype assignments.
All methods to block a confounding path (to deconfound) are based on conditioning, which means (in its basic form) restricting a variable to one of its values.
To avoid overloading the regression model, this analysis was restricted to variables shown to have a probable level of association with the outcome from the initial analyses (variables with a p-value of <0.2, Tables 2 and 3), and a backwards selection procedure was employed.
