1) Sex has certain theoretical benefits to (e.g., genetic recombination), but also carries risks. For example, species that are more promiscuous are potentially exposed to more sexually transmitted diseases. Researchers studying this phenonmena compared the immuno-activity of nine promiscuous versus nine monogamous species of primates by measuring the average white blood cell (cells/liter) count for each species.
(a) Is there a significant difference in the mean white blood cell count of promiscuous versus monogamous primates?
(b) Construct a series of power curves for this study showing the relationship between sample size (x-axis) vs. power (y-axis) for different effect sizes (separate curves on the plot). Use the standard deviation from the monogamous species data, assume a type I error of 0.05, and plot sample sizes from 5 to 25 species in increments of 5, with three different effect sizes: 500, 1000, and 2000 cells/l.
| Promiscuous | Monogamous |
| 5700 | 10400 |
| 7200 | 10400 |
| 7400 | 9900 |
| 8100 | 9100 |
| 9200 | 9200 |
| 9100 | 11900 |
| 9100 | 9300 |
| 10600 | 8900 |
| 8500 | 12500 |
Ans YES there a significant difference in the mean white blood cell count of promiscuous versus monogamous primates.
Applied Statistical test- t-test
Calculated P-value- 0.0102 Proving significant statistical difference.
1) Sex has certain theoretical benefits to (e.g., genetic recombination), but also carries risks. For example,...