Table 2.
Z-test of proportionality difference in rugae pattern distribution between Ikwerre and Igbo females.
Pattern | Tribe | Obs. population (n) | Sampled population (N) | Obs. proportion | z-value (calculated) | |z| critical | P value (obs.) | Inference |
---|---|---|---|---|---|---|---|---|
Wavy | Ikwerre | 117 | 289 | 0.405 | −4.7572 | 1.96 | <0.0001 | Significant difference in proportions ∗ |
Igbo | 188 | 314 | 0.599 | |||||
| ||||||||
Curvy | Ikwerre | 99 | 289 | 0.343 | 2.1791 | 1.96 | 0.02926 | Significant difference in proportions ∗ |
Igbo | 82 | 314 | 0.261 | |||||
| ||||||||
Circular | Ikwerre | 14 | 289 | 0.048 | −0.9672 | 1.96 | 0.33204 | No significant difference in proportions |
Igbo | 21 | 314 | 0.067 | |||||
| ||||||||
Straight | Ikwerre | 34 | 289 | 0.118 | 3.1373 | 1.96 | 0.00168 | Significant difference in proportions ∗ |
Igbo | 15 | 314 | 0.048 | |||||
| ||||||||
Converging | Ikwerre | 7 | 289 | 0.024 | 0.7289 | 1.96 | 0.4654 | No significant difference in proportions |
Igbo | 5 | 314 | 0.016 | |||||
| ||||||||
Diverging | Ikwerre | 18 | 289 | 0.062 | 3.5282 | 1.96 | 0.00042 | Significant difference in proportions ∗ |
Igbo | 3 | 314 | 0.01 |
The asterisks were used to demonstrate values with significant difference.