are infact detected but the means are generally small (< 1%) while the stan-
dard deviations remain within +1.5% and +1.8%. No significance was found for
differences between the left and right legs.
The main problems are caused by the large random "errors" in Cy and the
large systematic "errors" in Cp. It seems that the approximation of the lat-
ter circumference with a circle tends to underestimate it in a systematic
way. Despite the relatively small mean for VE on the contrary, the desper-
sion of differences is in this case considerably large. The knee joint in-
fact presents the most irregularly shaped profile and, further, it "moves"
vertically according to whether the muscles are relaxed or contracted. This
probably accounts for the magnitude of the variance. It should be further
added that the upper profile (C1)
above the x-axis, and displacements due to relief are present. Horizontal
is also often problematic: it is imaged
s.v. measurements through its marked point might thus include a portion of
the buttocks. In this case it was resorted to horizontal measurements
through the gluteal fold.
The linear regression equations of the type Ci-aD;*b, D, being the pho-
tographically obtained diameter and C; the directly measured circumference,
resulted in coefficients "a" ranging between 3.122 and 3.234 (very close to
n). See Fig. 3.
In this case, too, opposite-signed differences are partly compensating
for each other (overall mean difference +0.6% + 1.9% and +0.4% + 2.2% for
left and right legs, respectively).
Surface Area and Volume Calculations
The positive signs prevailing in circumference differences and the nega-
tive signs in height differences led to the assuption that surface area and
volume differences would be small. For both calculations the same truncated
cone formulae were used, and the results of Table III were obtained (see also
Fig. 4).
No significance was detected in the differences between direct anthropo-
metry and moiré calculations (or between left and right legs). The mean dif-
ferences are infact zero and the variances small. This, however, does not
allow any definite conclusions as to whether the legs can be actually regard-
ed as a sum of truncated cones.
Regarding volume calculation, in particular, direct anthropometry has
been checked against water-displacement methods by Jones and Pearson (1969).
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