October 2004: enhanced IStats report (version change to 5.4.5)

 

More information has been packed into the "IStats" report.  Its SMC values are now plotted in a series of ten bands, easing the task of determining the extent to which any single item relates to the others.

 

The first principal component, or the first principal factor, of the correlation matrix is now extracted, and item-component correlations are displayed in two ways: as a conventional row of values, and in the ten-bands format similar to that used for the SMC coefficients.  A technical paper was added to the website to demonstrate how to interpret this new output.  Read more about this in the eigenvalues topic.