Laserfiche WebLink
<br />l <br />-j <br />I <br />I <br />I <br />I <br />I <br />I <br />! <br />I <br />I <br />II <br />I <br />I <br />I <br />I <br />\ <br />I <br />I <br /> <br />Appendix B contains the snowpack evaluation, listing the observed average <br />control snowpack (C) ,the observed average target snowpack (Yo) ,the calculated <br /> <br />average snowpack (Ycl and the ratio of Yo/ Yc . Included with this listing is the ' <br />regression equation, the correlation coefficient and the results of the statistical tests that <br />were applied to the data. Table 5-2 summarizes this evaluation analysis. <br /> <br />Corr. Water Ratio: Excess Probabilities <br />Coeff. (r) Year Obs Precip. (P) <br /> 1993 Calc. (inches) t -test U -test <br />.922 1995 1.099 0.79 .204 .124 <br /> 1994 1.176 1.60 <br /> 1993 1.197 2.14 <br /> 3 years 1.162 1.51 .005 .006 <br /> <br />Table 5-2 <br />Summary of Snowpack Evaluations (1993-95 Water Year) <br /> <br />From Table 5-2 these results indicate the snowpack water content for the 1995 <br />water year averaged 9.9 percent more on April 1 than predicted. The evaluation <br />indicates as well that .79 inches of additional precipitation may have fallen over the <br />target than was predicted (7.94 inches). The student's t-test (one-tailed) shows results <br />were at a statistical significance of .204, and the u-test shows much the same at .124. <br />It generally takes several years of data (five or more) before the statistics reach a level <br />considered significant (.05). With only one season, any result will be inconclusive. The <br />three seeded ,year numbers indicate an average 16.2 percent increase. The statistical <br />analysis indicates the t-test (one-tailed) for the three years increases to .005 and the u-test <br />to .006. These tests show strong significance, and the results can be taken as very <br />encouraging. <br /> <br />5-8 <br />