A researcher is interested in whether students who attend private elementary schools do any better on s standard test of intelligence than the general population of elementary school children. A random sample of 75 students at a private elementary school is tested and has a mean intelligence test score of 103.5. The average for the general population of elementary school children is 100 (σ = 15).
a) Is this a one- or a two- tailed tests?
b) What are Ho and Ha for this study?
c) Compute zobt
d) What is zcv?
e) Should Ho be rejected? What should the researcher conclude?
f) Calculate the 95% confidence interval for the population mean, based on the sample mean.