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<br />Assessment and Evaluation <br />Weighted Sagebrush and Mt. Shrub Ref Area Std. 31.9% <br />T-test using total cover StDev of 12.1, and reduced sample size of 18 <br />Calculated T = 1.16 Critical T = 1.333 PASS <br />T-Test using herbaceous cover StDev of 11.6; Sample Size 18) <br />Calculated T = 1.21 Critical T = 1.333 PASS <br />T-test still indicates PASS, in both cases, and by a wider margin than with the sample size of 24. <br />The wider margin is due to the smaller sample size (loss of statistical power, wider conf. Interval). <br />However, with the smaller sample size, sample adequacy was not achieved for total vegetation cover <br />or herbaceous vegetation cover. As a result, even though the t-test indicates success, the <br />conclusion is that the result is not statistically valid.