One subject did not qualify based on screening laboratory tests.
Based on the screening of variables by 2-level Plackett Burman design, full-factorial central composite design (CCD) was developed for variables significantly affecting biomass production and consisted of five levels: the low and high levels (−1 and +1), central points (0) and star points with α ± 1.68, giving twenty combinations of cultivation parameters as shown in Table 2.
Data on variables were measured based on variable description and variable type [see Additional file 2].
We also attempted restricting the number of variables included in PCA by pre-screening them based on their Principal Variables rank and leaving only variables that explained high amounts of total variance in the dataset.
The method was optimized regarding its instrumental conditions through a multivariate strategy based on the screening of the variables, to identify the significant ones, followed the application of a response surface methodology.
The testlet assigned in Stage 2 was based on background variables, the cognitive screener and the respondent's performance on the set of items administered in Stage 1.
To address the limitations of classical screening tools, we propose a simple screening algorithm, based on readily available variables: age, neck circumference, and time on renal replacement therapy.
We searched for articles using electronic retrieval based on the keywords "variable selection", "variable screening", and "multivariable", and hand searched all articles that were not selected electronically in order not to miss any articles that may involve selection of variables.
This is when the tracking company (or government agency) gives your PC a unique identifier based on variables such as screen resolution, browser version, extensions, fonts, timezone and so on.
The following is a segment about this validation of our PCA approach that we now include in the Methods section of the paper: "We also attempted restricting the number of variables included in PCA, by pre-screening them based on their Principal Variables rank there is no objective post-hoc test to justify the use of one restricted model over another (Guyon and Elisseeff, 2003).
