1.1 Collecting data
Data is a collective name for information recorded for statistical purposes. There are many different types of data, which we will discuss in this section.
Data can be collected in several ways. These include face-to-face or telephone interviews, or asking participants to complete questionnaires in person or by post. Data can also be collected online via an internet search or through other more active data- collecting methods, such as counting the number of passengers on a bus at a specific time of day.
When data is collected from an original source for a specific purpose, this is known as primary data. For example, a learner who is investigating the most popular make and model of cars in their town might count cars which pass a particular set of traffic lights. When data is not collected from an original source, this data is secondary. For example, a learner might find data on goals scored in the football Premier League last year in order to investigate whether strikers from a particular country score more goals on average. Since the data was not collected for this purpose originally and was not collected by the learner themselves, this data is secondary.