Reliability HotWire is a monthly eMagazine by ReliaSoft providing information and tips on how to best improve your reliability practices and get the most out of ReliaSoft’s tools for reliability and life data analysis.
This Month’s Hot Topic
The Importance of Looking at the Probability Plot When Fitting a Model Using Least Squares Regression
The correlation coefficient, ρ, provides a measure of the fit of a model to a set of data points. For most real data sets, the absolute value of ρ lies between 0 and 1, with a higher value of ρ indicating a better fit of the model to the data (i.e., when ρ = -1 or ρ = 1 the model fits the data perfectly, and when ρ = 0 it does not fit at all). In fact, some practicing reliability engineers use a threshold value of ρ (e.g., 0.9) to determine that their model adequately fits the data. However, when fitting a model to data, it is important to evaluate the probability plots in addition to the value of ρ before drawing the conclusion that the proposed model is a good fit to the data.
For full article, view: Reliability Hotwire – Issue 185 July 2016