Operational measures of the characteristics of <a href="search.pl?p=time-series">time-series</a> or <a href="search.pl?p=cross-sectional data">cross-sectional data</a>. Examples include <a href="search.pl?p=basic trend">basic trend</a>, <a href="search.pl?p=coefficient of variation">coefficient of variation</a>, and <a href="search.pl?p=discontinuity">discontinuity</a>. <o:p></o:p></P>