Laserfiche WebLink
Use of a reverse-null t-test of the assertion that the 2018 BRB-5 Background woody plant density exceeds <br /> 90% of mandatory performance standard 1 (200 stems per acre)is shown as follows: <br /> z — (0.9 * technical standard) <br /> t� = s <br /> — 20.8 — (13.4)t = 2.088 <br /> 19.9 <br /> 32 <br /> Since critical tt= 0.853 (one-tailed, alpha= 0.2, 32-1 df) and tcalc (2.088)is greater than this critical <br /> value, reclamation success for the WPD mandatory performance standard 1 under Phase III in 2018 is <br /> demonstrated. It should be noted that the same result would have been achieved using raw values (tcalc= <br /> 3.097 which exceeds tt= 0.853). <br /> In 2018, the mean density in the Volunteer Concentration area of the BRB-5 (2,165.1 stems per acre) <br /> exceeded 90% of the mandatory performance standard 2 (900 stems per acre). <br /> 2019 Woody Plant Density Success Evaluation <br /> In 2019,the 677.9 stems per acre observed in the Background area exceeds 180 stems per acre(90 percent <br /> of the 200 stems per acre mandatory performance standard 1). The average woody plant density data in the <br /> Volunteer Concentration area of 1,296.1 stems per acre exceeds 900 stems per acre (90 percent of the <br /> 1,000 stems per acre mandatory performance standard 2). <br /> Sample adequacy based on woody plant density was not achieved in the"Background" areas of the <br /> Phase III BRB-5 in 2019. The mean"Background" woody plant density exceeded 90% of the mandatory <br /> performance standard 1 (Figure D-3, Table C-1)in 2018. Thus, reclamation success under Phase III for <br /> woody plant density is demonstrated by passing a one sample t-test of the "reverse null" hypothesis <br /> (CDMG 2005 revised rule, 4.15.11 (2)(c)). The BRB-5 "Background"woody plant density data were first <br /> evaluated for normality using the Shapiro-Francia test. Based on the raw stems per acre density data; the <br /> normality test was not passed in 2019. Consequently, a square root transformation was performed and the <br /> normality test was passed in 2019 (Tables 3 and 5 above). Hypothesis testing calculations went forward <br /> using square root transformed data for both the"Background" density data and the technical standard. <br /> Use of a reverse-null t-test of the assertion that the 2019 BRB-5 Background woody plant density exceeds <br /> 90% of mandatory performance standard 1 (200 stems per acre)is shown as follows: <br /> z — (0.9 * technical standard) <br /> t� = s <br /> 13 <br />