Chapter 1 For each survey, describe the target population, sampling frame, sampling unit, and observation unit. Discuss any possible sources of selection bias or inaccuracy of responses. 0 Problem 3. Amazon books (http://www.amazon.com) summarizes reader reviews of the books it sells. Persons who want to review a book can submit a review online; Amazon then reports the average rating from all reader reviews on its website. a Problem 5. Many scholars and policy makers are interested in the proportion of homeless people who are mentally ill. Wright (1988) estimates that 33% of all homeless people are mentally ill, by sampling homeless persons who received medical attention from one of the clinics in the Health Care for the Homeless (HCH) project. He argues that selection bias is not a serious problem because the clinics were easily accessible to the homeless and because the demographic proles of HCH clients were close to those of the general homeless prOpulation in each city in the sample. Do you agree