PERMFILE122647

• Permit No: C1984065
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Doc Name: Statistical Formulas Used in Quantitative Analysis
• Section_Exhibit Name: Appendix 3.6-1 Appendix A
• Media Type: D
• Archive: No

i _
I:
`- Study Area And Reference Area Statistical Comparison Using A One-Tailed t-test:
^• Calculation Of t
r- V s(xi - z ) + E(xi - z ) SED = V (~' + ~
n• + n.. _ 2
- where
~ xi = study area cover, production or density value at i sample point
z = study area sample mean of production, cover or density
_ xi = reference area cover, production or density value at i sample point
z~ = reference area sample mean of productfion, cover or density
^ n~ = study area number of production, cover or density points
_• n = reference area number of production, cover or density. points
-~ V = pooled estimate of variance
SED = standard error of difference of the means
t - ~(Xi - XI,)~
- SED
where
t = calculated t value for comparison with observed t values from
Table III - Fisher and Yates at n + n - 2 degrees of freedom.
_ Calculated t values less than the observed t indicate no
statistical significant difference between the two means.