Jamieson and Romer (2008) evaluated children's beliefs concerning life expectancy in a diverse sample of American children. In their study, they reported at a 95% CI that "approximately 1 out of every 15 youth interviewed (6.7%[5.9%, 7.5%]) responded that they agreed they would not live much past the age of 30" (p. 154).
(a) What is the point estimate and interval estimate for these data?
(b) If these researchers computed an 80% CI, how would this change the precision and certainty of their estimate?