When the 217Plus model is selected, a tailored A0 value for Bayesian equations can be specified for the 217Plus model in the properties for the Prediction Bayesian file. The A0 value is the effective number of failures associated with the predicted failure rate. The default value, 0.5, represents the large degree of uncertainty inherent in the failure rate estimate when a diverse data set is used. If you have enough data to obtain an observed uncertainty, you can enter a different A0 value under Bayesian in the file properties for this support file. For more information, see Support File Properties.