Table 1 (cont'd). Results from sampling location 1, Monite site.
b. Statistical analysis of TNT concentrations (g/g)
for discrete and composite samples.
Discrete samples
On-site analysis
Laboratory total
Sample
Mean
Mean of logs
Mean
Mean of logs
4.599a†
1
39,800
41,400
4.615a
2
500
2.699e
416
2.619e
3
164
2.214g
136
2.132g
4
27,800
4.444b
42,800
4.632a
5
24,400
4.387c
27,700
4.434c
6
1,280
3.105d
1,220
3.087d
7
331
2.519f
286
2.452f
†
Numbers designated with the same letter are not significantly different at the
95% confidence level.
ANOVA for log on-site analyses
ANOVA for log lab analyses
F ratio = 233***
F ratio = 613***
Error MS = 0.0005547
Error MS = 0.00396
Least sign. diff. = 0.056
Least sign. diff. = 0.149
Linear correlation analysis for on-site analysis vs. lab analysis
(r = correlation coefficient)
Slope
Intercept
r
untransformed, non-zero intercept
0.805
359.1
0.973
untransformed, zero intercept
0.815
0
0.973
log-transformed data
0.926
0.251
0.999
Results of paired t-tests for on-site vs. lab results
Means of seven discrete samples, t = 1.35 (NS)
Means of log values for seven discrete samples, t = 0.07 (NS)
Composite samples
On-site analysis
Laboratory total
n
7
7
mean value
13,100
14,100
standard deviation
532
1,420
RSD
4.06%
10.1%
ANOVA comparing on-site and lab analyses
F ratio = 3.05 (NS at 95% level)
* Significant at the 95% level
*** Significant at the 99.9% level
** Significant at the 99% level
NS Not significant at the 95% level
Results of a least significant difference test (LSD)
Thus, to perform analysis of variance (ANOVA),
showed that all seven discrete samples were sig-
we transformed data by taking the logarithm of
nificantly different from each other at the 95%
individual values (Table 1b). This was done for
confidence level. Similar results were obtained
both the field and laboratory results and an
when ANOVA was done on the laboratory results
ANOVA was conducted on both sets of log-trans-
(Table 1b). An F ratio of 613 was found, which
formed data (Table 1b). For the on-site analyses,
was significant at greater than the 99.9% level,
the F ratio was 233, indicting that a significant
and the least significant difference test indicated
difference was detected among the seven discrete
that all samples were statistically different from
samples at greater than the 99.9% confidence level.
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