WJEC Maths for AS: Applied sample

9 Introduction In order for statistics such as mean, mode, median, range, etc., to be obtained from data, the data must first be collected. If the data is not collected properly to start with then obtaining statistics from it will be a waste of time as they will not be accurate. Obtaining accurate statistics depends on the proper collection of data and thought needs to be given as to how best to do this. In this topic you will learn about how to take a smaller sample of the complete data set called the population so that accurate and meaningful statistics can be produced. This topic covers the following: 1.1 The terms population and sample 1.2 Using samples to make informal inferences about the population 1.3 Sampling techniques: simple random sampling, systematic sampling and opportunity sampling 1.4 Selecting or critiquing sampling techniques