Laserfiche WebLink
Formulas used in cover, production, density, species diversity and t-test <br />quantitative analysis. <br />_~•, 1. Determining Standard Deviations <br />Cover and Production Density <br />s = s zn _ z or s - s(Di - 6)2 <br />r n - 1 <br /> where <br />_ zi = sample mean per quadrat in the ith exclosure or transect <br /> x = Ezi = overall mean per quadrat <br />- n <br /> n = number of exclosures, transects, or density points <br /> Di = density for a point <br />_ 6 = E~i = overall mean for vegetation type <br /> n <br /> 5 = standard deviation <br /> <br /> 2. Estimating Adequate Sample Size <br /> Cover and Production Density <br />- "min '_ 2 sz 2 or nmin '- 2 sz 2 <br />(dx) (d6) <br />_ where <br /> n <br />i = minimum number of clipping quadrat, cover transects or density <br /> m <br />" paints in this vegetation type <br />.. s = sample standard deviation <br />- z = the z statistic (1.28 far cover and 0.84 for production and density) <br /> d = amount of reduction it is desired to detect (0.1 for cover and <br /> 0.2 for production and density) <br /> z = sample mean of production per quadrat or percent cover per transect <br />- 6 = sample mean of density per point <br />• <br />