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for 1) woody cover, 2) excess annuals or 3) noxious weeds are done either on a sample by sample basis <br />or by subtracting the average cover of 1), 2) or 3) from each sample. Choice of method is done with the <br />goal of achieving the lowest overall sample variance. The specific deduction method used is done for all <br />data sets (i.e reclamation as reference areas) for that parameter (i.e. cover or production). <br />It is also to be noted that the data from the two reference areas is weighted in accordance with the <br />original relative abundance of the types in the pre- mining landscape (83% mountain brush, 17% <br />sagebrush /snowberry). It was necessary to sample each to adequacy (see above) but in the process of <br />weighting, a reliable estimate of variance is lost. Thus the reference area standard is thereafter in the <br />process treated as a technical standard (i.e. without confidence limits) and one - sample t- testing is used. <br />HYPOTHESIS TESTING APPROACHES <br />For formal hypothesis testing relative to Phase III Bond Release, the following procedures were followed: <br />Cover and Production <br />Phase III Revegetation success for cover and production was tested by one of following statistical <br />approaches. <br />If sample adequacy has been achieved (minimum of 15 samples) in the BRB PSCM -1 and the reference <br />areas, and the reclaimed area mean total allowable herbaceous cover and /or mean allowable herbaceous <br />production are above 90% of the reference area - derived standard, then revegetation would be deemed <br />successful (CDMG 2005 rules 4.15.1 (2)(a)). <br />Were the mean allowable herbaceous cover and/or production of the reclaimed area above 90% of the <br />reference area - derived standard, but sample adequacy was not met (with a minimum of 30 samples), <br />then the hypothesis testing would proceed using a parametric one - sample test of the "reverse -null" <br />hypothesis. This would be conducted using the following expression (CDMG 2005 rules, 4.15.11 (2)(c)): <br />t _ <br />x —Q <br />c <br />S— <br />x <br />Where: x = Bond Release Block Sample Mean <br />Q = 90% of Standard <br />S_ = Standard error of mean [s/ - ] <br />x <br />S = Sample standard deviation <br />n = Sample size <br />t = Calculated t value <br />t = Table t value (alpha = 0.2) <br />6 <br />