derived variable

derived variable

In a clinical trial, a new variable created as a function of existing variables and/or by applying mathematical functions.
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AC and DC data were further used to calculate a derived variable, perfusion index (PI), which is defined as PI = AC/DC * 100%.
where u([x.sub.1], [x.sub.2], ..., [x.sub.n]) is the formula that gives the derived variable as a function of the fundamental variables [x.sub.1], [x.sub.2],..., [x.sub.n]), [k.sub.i] is the factor used to change units in variable i, [t.sub.i] is the l ocation change of variables i, and T and K are functions associated with the location and scale changes of the derived variable, respectively.
We need to target employment growth as a key variable and not as a derived variable. In addition to the sectoral allocations, which have to be made on employment intensity basis, we need direct interventions in sectors that hold high employment potential, he added.
Aside from SOS and BUA, the most common derived variable is 'stiffness', a linear combination of SOS and BUA.
The standard model is then re-fit using the derived variable [Z.sub.1t], referred to as the first principal component, in place of the k original pollutant variables [X.sub.it], i = 1,.., k:
From ROC analysis, the derived HPLC variable Vs + Ls - Hs produced the greatest AUC, indicating that this variable was a more powerful discriminator than any other derived variable, including traditional risk markers.
Various asymptotic and polynomial models were examined for each of the dependent variables, in terms of the independent variables N, [DELTA]T, and the derived variable TP.
The first is whether average biomass, which Weller calls a derived ratio, is a derived variable in the sense of Sokal and Rohlf (1981).
The tools must be suitable for the different stages of the data processing process: material acquisition: processing and quality assurance of different data sources editing of data: aggregation, classification, and other derivation of derived variables statistical analysis: a comprehensive range of methods from spreadsheets to advanced statistical models and machine learning publication: visualization and usability of results in reporting and applications.
His main focus is on the steady state of alternating and direct current networks, because the knowledge of state variables is important in order to determine the value of derived variables such as currents, real and reactive power flows through each element, losses, and the reactive power requirements.
Thus treated signals were subsequently computed to calculate some derived variables, to get a complete and useful description of the system.
Most of these efforts emphasize on the correlation analysis of the data, however some of the researchers also focused on the combination of mathematical formulation to resort the derived variables by squaring, averaging, adding or differencing the data sequences to determine the appropriate input variables [12].