842 
Fishery Bulletin 95(4), 1997 
classes were similar to one another and were small 
relative to the size of a contingency table, Fisher’s 
exact test was used instead of a chi-square test (Zar, 
1984). All tested cases supported the null hypoth- 
esis of independence between sex ratio and depth, 
except for the samples of 200-249 mm TL fish caught 
with traps during 1982-84 (Table 3). After allowance 
for multiple-testing (a'=0. 05/18=0. 0028), none of the 
cases was statistically significant. 
Since there were no significant differences among 
depth classes, we pooled the data from all depth 
classes to compare the percentage of females among 
Table 3 
Comparison of percentages of females among water depth-classes with the same latitude (32°00'-32°59' N), length ranges (TL=200- 
249 mm and 250-299 mm), period, and gear type. % = female percent, n = the total number of male and female fish. The null hypothesis 
( H 0 ) = sex ratio is independent of depth. Blanks indicate no or few samples available for comparison, df = degrees of freedom. 
Period 
Depth 
midpoint 
(m) 
Traps 
Hook-and-line 
Trawl 
TL=200-249 TL=250-299 
% n % n 
TL=200-249 TL=250-299 
% n % n 
TL=150- 
% 
-199 
n 
TL=200- 
% 
-249 
n 
1979-81 
25 
54.6 
55 
53.9 
39 
35 
66.7 
48 
59.7 
62 
chi-square 
1.572 
0.333 
P 
0.210 
0.564 
df 
1 
1 
Reject H 0 
No 
No 
1982-84 
25 
83.3 
18 
100.0 
2 1 
66.7 
15 
57.7 
26 
58.9 
35 
91.7 
36 
84.6 
13 
64.7 
17 
80.0 
10 
65.2 
45 
67.1 
152 
69.1 
97 
74.4 
43 
71.6 
109 
55 
80.0 
45 
75.6 
41 
75.0 
8 
40.0 
15 
chi-square 
11.28 
1.708 
Fisher’s 2 
Fisher’s 2 
0.314 
P 
0.010 
0.426 
0.859 
0.056 
0.575 
df 
3 
2 
1 
Reject H 0 
Yes 
No 
No 
No 
No 
1985-87 
25 
57.9 
35 
62.2 
45 
86.9 
206 
72.4 
134 
68.6 
51 
63.9 
72 
55 
76.7 
60 
82.4 
34 
61.4 
44 
71.2 
59 
chi-square 
3.727 
1.414 
0.550 
0.783 
0.132 
P 
0.054 
0.234 
0.458 
0.376 
0.716 
df 
1 
1 
1 
1 
1 
Reject H 0 
No 
No 
No 
No 
No 
1988-90 
25 
82.7 
81 
73.7 
19 
61.8 
34 
35 
77.1 
48 
79.0 
19 
45 
72.5 
189 
67.1 
176 
65.1 
126 
60.0 
45 
55 
64.9 
74 
75.0 
76 
70.0 
60 
71.8 
39 
chi-square 
6.808 
2.484 
0.745 
1.286 
P 
0.078 
0.478 
0.689 
0.257 
df 
3 
3 
2 
1 
Reject H 0 
No 
No 
No 
No 
1991-93 
25 
80.0 
30 
84.6 
13 2 
35 
74.5 
47 
80 
20 
45 
70.0 
30 
77.9 
68 
55 
64.4 
160 
73.5 
102 
chi-square 
3.910 
0.649 
P 
0.271 
0.723 
df 
3 
2 
Reject H 0 
No 
No 
1 The row was discarded from the contingency table because of its excessively low expected frequency. 
2 When conditions for a chi-square test were not met, Fisher’s exact test was used. 
