was used. This coefficient is simply the standard deviation divided by the mean and is particularly useful in defining the degree of spread of samples with widely different means (Wine, 1964). Koch and Link (1971b) present a technique for comparing two coefficients They suggest that of variation for data sets with large sample sizes. the coefficient of variation is approximately normally distributed. They present a test statistic for determining whether two coefficients of variation can be considered to be drawn from populations with the This same test statistic was used, but to same population coefficient. accommodate the small sample size, the more general t distribution was However, inequality in sample variances causes the test statistic used. to no longer follow the student t distribution; therefore, the confidence level was adjusted following a procedure given in Snedecor and Cochran (1976; pp. 115-116). It is not known whether these modifications of the Conclusions resulting from the procedure test are appropriate or valid. given about should be considered to be tentative and suggestive and are The computation equation used was: certainly not definitive. C, - Cy (= 2 2 (1+2C, ) (df, /N,) 2df, + Cc, 2 2 (142C, ) a | 1/2 2df, Where t“ is the test statistic and the level of significance is approximated by using the t table and calculations outlined in Snedecor and Cochran (1976; pp. 115-116). C, and Cy are the coefficients of variation for sample groups one and two (i.e., the top l-cm and 5-cm sampling, respectively); df, and df are the number of degrees of freedom associated with variance calculation for sample groups one and two; and N) and No are the number of observations in each group. When t~ exceeds the critical value, the significance between the two coefficients is denoted at some preselected confidence level and the ruling hypothesis is rejected and the altemate hypothesis is accepted. Site Il The sampling coefficient of variation for the l-cm samples was 0.688 as compared to 0.471 for the 5-cm samples. The ruling hypothesis is that the coefficient of variation for the l-cm samples is the same as that for the 5-cm samples at Site I. The alternate hypothesis is that the coefficient of variation for the l-cm samples is not the same as that for the 5-cm samples. The t” statistic for comparing these two coefficients of variation is 1.53 with four degrees of freedom. The critical value at the 95 percent confidence level is 3.18. Therefore, the ruling hypothesis is not rejected. Site IT The sampling coefficient of variation for the l-cm samples was 0.177 as compared to 0.265 for the 5-cm samples. The ruling hypothesis is that 677