Exercise 5-1. Sometimes students can be confused by terms that describe similar but distinctly different concepts. This confusion is often exacerbated when it comes to methodological terms. This exercise is about reinforcing your understanding of similar terms. For each of the word pairs below, define each term and then explain the important differences between them. Population parameter and estimator ____________________________________________________ ____________________________________________________ ____________________________________________________ Sampling frame and sampling unit ____________________________________________________ ____________________________________________________ ____________________________________________________ Element and stratum ____________________________________________________ ____________________________________________________ ____________________________________________________ Probability sample and nonprobability sample ____________________________________________________ ____________________________________________________ ____________________________________________________ Proportionate and disproportionate sample ____________________________________________________ ____________________________________________________ ____________________________________________________ ____________________________________________________