-&3-
Variability
In view of the variety of conditions of locality, time, and
personne] involved in the study, considerable variability in the
results is to be expected.
The statistical nature of the vari-
ability in algae,
invertebrates, and fish is dealt with in
another report (Bonham, 1956).
For invertebrates, the coeffi-
cients of variation of the values of radioactivity for a tissue
in a collection appear in Table 22.
Taole SB.
Saam ceoffictent ef vertetion in pereent, of
selves of redicastivity ia tiseves ef invertetretes
collested tn 1066 at Belle efter Sester.
Tiee
-
PPrarVes
mnele
Qut or visceral ance
se
oe
se
sl
ss
Ce
os
«a
Liver
mantle
aaa
Shell ev carepace
+*
se
33
a
a
n
-“a
3
2
2»
30
oo
-o-
intequnent
Jenad
-°
--
“
23
These mean coeffic.ents are averages of 7 to 30 individual
coefficients of variation calculated from the few (2 to 10,
average 2.8) values for a tissue in each collection that involved more than one sample.
were averaged for Table 22.
Approximately 300 coefficients
These ranged from 3% to 125¥ and
were distributed asymmetrically with the peak strongly toward
the left at about 20% to 30%, and the mean at 406.
Coefficients of variation were nighest (424 to 61%) for gut
and shell, and markedly lower (28% to 43%) for muscle.
For the declines, the variability of the points about the
regression lines is measured by the correlation coefficient in
the last two columns of Table 1.
The correlation is best where
the data are most numerous.