Standard Practice for Evaluating Test Sensitivity for Rubber Test Methods

Importancia y uso:

5.1 Testing is conducted to make technical decisions on materials, processes, and products. With the continued growth in the available test methods for evaluating scientific and technical properties, a quantitative approach is needed to select test methods that have high (or highest) quality or technical merit. The procedures as defined in this practice may be used for this purpose to make testing as cost effective as possible.

5.2 One index of test method technical merit and implied sensitivity frequently used in the past has been test method precision. The precision is usually expressed as some multiple of the test measurement standard deviation for a defined testing domain. Although precision is a required quantity for test sensitivity, it is an incomplete characteristic (only one half of the necessary information) since it does not consider the discrimination power for the FP (or constituent) being evaluated.

5.3 Any attempt to evaluate relative test sensitivity for two different test methods on the basis of test measurement standard deviation ratios or variance ratios, which lack any discrimination power information content, constitutes an invalid quantitative basis for sensitivity, or technical merit evaluation. Coefficient of variation ratios (which are normalized to the mean) may constitute a valid test sensitivity evaluation only under the special condition where the two test methods under comparison are directly proportional or reciprocally related to each other. If the relationship between two test methods is nonlinear or linear with a nonzero intercept, the coefficient of variation ratios are not equivalent to the true test sensitivity as defined in this practice. See discussion of example in X1.1.4. The figure of merit defined by test sensitivity and its various classifications, categories, and types as introduced by this practice permits an authentic quantitative test sensitivity evaluation.

Subcomité:

D11.16

Referida por:

D7605-11R22, D4483-20, D4483-20

Volúmen:

09.01

Número ICS:

83.040.01 (Raw materials for rubber and plastics in general)

Palabras clave:

absolute test sensitivity; calibration material; reference material; relative test sensitivity; signal-to-noise ratio; test sensitivity;