In a study of Seychelles warblers, researchers genetically assessed 5 subordinate female birds that did not help feed the offspring of older birds to determine if they were related. The mean relatedness score was -0.05 with a standard deviation of 0.45, where a score of 0 means no relationship. The question asks to calculate the 95% confidence interval for the relatedness of unhelpful subordinates to the offspring.

1. In Seychelles warblers, young adult females known as subordinates sometimes hang around the
terrirories of older birds. Sometimes these subordinates help feed the offspring of the older birds,
and sometimes not. In one study, subordinate birds that did not help were genetically assessed to
discover whether they were realted to the offspring of the older birds (Richardson et al. 2003.) A
"relatedness" score was assigned to each subordinate, with a value of zero meaning no
realtionship to the offspring. Out of five subordinates examined, the mean relatedness was -0.05
with standered deviation 0.45 (relatedness can be negative if by chance sampled individuals are
less related than the population as a whole.) What is the 95% confidence interval for relatedness
of unhelpful subordinates to the offspring?
Solution