A national association devoted to human resource (HR) and workplace programs, practices, and training wants to study HR department practices and employee turnover of its member organizations. HR professionals and organization executives focus on turnover not only because it has significant cost implications but also because it affects overall business performance. A survey is designed to estimate the
proportion of member organizations that have both talent and development programs in place to drive human capital management as well as the member organizations' mean annual employee turnover rate (the ratio of the number of employees that left an organization in a given time period to the average number of employees in the organization during the given time period). A previous survey found that the standard deviation of member organizations' annual employee turnover rates is approximately 5%.
a. What sample size is needed to have 99% confidence of estimating the population mean annual employee turnover rate to within ±1.5%?
b. How many member organizations need to be selected to have 90% confidence of estimating the population proportion of organizations that have both talent and development programs in place to drive human capital management to within ±.045?