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An example computer output is as follows: <br /> Kendall Rank Correlation for chloride, date <br /> Score 85.0000 <br /> Tau .368 <br /> Z-Value 2.397 <br /> P-Value .0165 <br /> Tau corrected for ties .375 <br /> Tied Z-Value 2.439 <br /> Tied P-Value .0147 <br /> # Ties, chloride 4 <br /> # Ties, event 0 <br /> One case was omitted due to missing values <br /> The parameters given in the output are <br /> Score = Mann-Kendall statistic ( ) <br /> The Kendall-tau method assigns a positive or negative score based on the <br /> differences between the data points. The first step is to list the data in the <br /> order in which they were collected over time, and then determine the sign <br /> of all possible differences. <br /> The Mann-Kendall statistic (S) is then computed, which is the number of <br /> positive differences minus the number of negative differences. If S is a large <br /> positive number, measurements taken later in time tend to be larger than <br /> those taken earlier, i.e., an upward trend. Similarly, if S is a large negative <br /> number, measurements taken later in time tend to be smaller, i.e., a <br /> downward trend. <br /> A large positive number of 85 is shown in the example; therefore, an <br /> upward trend is likely. <br /> Tau = Kendall's Rank Correlation <br /> SAC/pjft93M390011.8a1-94 lfc:9 C-2 Rev.0,October 28. 1994 <br />