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I have worked throught the statistical analysis of the Wyoming Fuel vegetation data and have a number of comments. I will group and present them under specific topics. Fl1RT11 ii.AF. 1) The applicant needs to provide the t-test formula utilized in the statistical analysis. FORMULAE VALUES 1. The regulations (1.04.135) define woody plant communities as those with equal or greater than 15% canopy cover of woody plants relative to total vegetative cover. Therefore in the calculation of sample adequacy the applicant is allowed to utilize an BO% confidence level. Wyoming Fuel has utilized a 90% level which gives an over estimations of the number of samples needed, for 1979 and 1980 cover data for Big Sagebrush and Alkali Sagebrush. 2. It is Division policy to have applicants achieve an accuracy which is within 10% of the sample mean. Sdyoming Fuel has utilized a 20% accuracy for calculation of sample adequacy for 1979 and 1980 production data for Big Sagebrush and Alkali Sagebrush. By doing so they have caused themselves to undersample the Alkali Sage Reference area for production (1979, 1980), Alkali Sage permit area for production (1980), the Big Sage brush permit area for production (1979), Big Sagebrush Reference area for production (1979), Alkali Sagebrush woody plant densities for reference areas and permit areas (1980), and Big Sagebrush • woody plant densities for permit and reference areas (1980). 3. Table 8F presents mean values for the Big Sagebrush vegetation type which are different than those values in Table 1F. Wyoming Fuel should clarify this discrepancy. 4. Table 9F values do not correspond to values presented in Tables 1F and 2F. Consistency should be maintained in the method of expressing % values. STATISTICAL ANALYSIS (PERMIT vs. REFERENCE) III 1 1979 BIG SAGEBRUSH COVER `, The analysis was not checked due to the data discrepancy noted above. 2~)i'1979 ALKALI SAGEBRUSH COVER The applicant has utilized the wrong critical t-value, however this does not cause the rejection of Ho. The permit and reference areas are statistically equivalent with 95% confidence ( (2)). 3.~ 1980 BIG SAGEBRUSH COVER yP/, The applicant has utilized the wrong critical t value which does not affect the ,,outcome. The permit and reference areas are equivalent with 95% confidence ( (2)). 4., 1980 ALKALI SAGEBRUSH COVER (•~~ The applicant has utilized the wrong critical t value but has not affected the outcome. The permit and reference areas are equivalent with 95% confidence ( (2)).