The plot of the measurements is shown in Appendix E. As we have only two PSDs to average, and no indication of the methods used to disperse the material for analysis, it is not possible to determine the specific reasons for the observed variations. It is also impossible to determine the outlier, other than by comparing with the other methods distribution. In that case the set R is an outlier. Table 8 shows the median for the two sets with the standard deviation and the median for the set W (the set supposedly correct). The median values of W are lower than the average of the R and W. On the other hand, the set W was also considered an outlier when SRM 114p was analyzed (see Section 3.1.1). As we have no other data, there is no possibility of determining a better value for this method.
|Table 8: Average median diameter from EZS method.|