Measurement confidence

Unpaired Data Consider two samples, A and B, for which mean values, Xa and Ab, and standard deviations, sa and sb, have been measured. Confidence intervals for Pa and Pb can be written for both samples... 

Equipment failure rate data points carry varying degrees of uncertainty expressed by two measures, confidence and tolerance. Confidence, the statistical measurement of uncertainty, expresses how well the experimentally measured parameter represents the actual parameter. Confidence in the data increases as the sample size is increased. 

When estimating measurement results, the important thing is not only to know its accuracy but also the measurement confidence. The degree of measurement the confidence is estimated from confidence interval as defined by the level of significance. Let X denote the actual measurement value and AX the error in measuring... 

This problem may set up another problem. What is the probability for X=1.27 and S=0.032 results of individual measurements not to fall outside the measurement confidence interval 1.19[Pg.193]

Hence, calculations from relation (2.26) facilitate determining the necessary number of measurements (u). Thereby, it is of course necessary to previously define the size of the random value that may be accepted and the coefficient or degree of measurement confidence. In practice, we are satisfied with the level that is not above 0.5%. Table 2.11 is used for practical determination of the necessary number of measurements, for known measurement confidence 1-a and for different confidence interval limits expressed by the error mean square of measurement AX/S. 

The error curve and the measurement Confidence limit Significant figures Correct values... 

Use of Bayesian belief networks to predict software quality has been proposed previously. [Hall, May, et. al, 1992] working on the FASGEP project used BBNs to measure confidence in the level of integrity of software design process, based on prediction of fault numbers. Fenton in [Fenton, Neil, 1999] present a critique of existing defect prediction models such as Multivariate approach and size and conplexity metrics and also conclude that BBNs offer some attractive benefits conpared to the existing software metrics techniques. 

Confidence scales focused on delivering different aspects of the Primary Science National Curriculum required in English schools followed. This five-point scale measured confidence towards different science content, investigations and pedagogy and was also developed from Hargreaves et al. (1996). 

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