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The null hypothesis being tested is that the mean value at the reclaimed site is less than <br />or equal to Q, with 80% statistical confidence. If t, is greater than the 1- tailed t table <br />value for alpha error probability of 0.20, at n -1 degrees of freedom (infinite degrees of <br />freedom may be used if n > 30), then the null hypothesis is rejected, and revegetation <br />is deemed successful for the parameter in question. <br />4) If sample adequacy is not achieved in the reference area (regardless of whether <br />sample adequacy is achieved in the reclaimed area), success will be demonstrated by use <br />of the two - sample "reverse null" t-test with Satterthwaite approximation of standard error <br />and degrees of freedom. The test can be used if the following 2 conditions are met: 1) <br />a minimum of 30 sample observations are taken in the reclaimed area and also in the <br />reference area, and 2) the reclaimed area sample mean is greater than Q. <br />To use this test, first the Satterthwaite standard error is calculated as <br />( � SO) 2 <br />ntr T rN� <br />Y <br />Where: <br />SEsat = Satterthwaite- approximated Standard Error <br />sbr = bond release site (reclaimed site) sample standard deviation <br />s = reference area sample standard deviation <br />nbr = bond release site (reclaimed site) sample size <br />n, = reference area sample size <br />Next, the Satterthwaite degrees of freedom are calculated as <br />(S y <br />( ( h )`l ((aJ(sE,)) <br />Where: <br />dfsat = Satterthwaite- approximated degrees of freedom <br />Lastly, a one -sided reverse -null t-test with alpha = 0.20 is used as follows: <br />X —((0 9)X„ <br />t = SE <br />Where: <br />REVISED 11 Nov 09 Tab 22 -30 <br />