It is vitally important that students appreciate the steps involved in a complete statistical investigation. They should experience the following key aspects.
- Students should be aware that it is necessary to collect valid samples of the required data that are random, fair and representative.
When analysing data to answer a statistical question, it is often helpful to create a graphical representation.
Students should build a repertoire of graph types and know how to select the most suitable type.
It is also often necessary to summarise the information in a single statistic.
Students should be able to select the measure that is most appropriate for their data and the question they wish to answer.
Making decisions about populations, based on evidence from samples, is at the heart of statistics.
Students need repeated exposure to decision-making that leads to informal inferences.
Students will use their statistical understanding outside school.
They need to develop critical thinking in contexts where statistical claims are made.
The success of a statistical investigation is largely dependent on the quality of the data collected.
The type of data representation used for a statistical investigation depends on the question asked, the type of data collected and the number of data values to be displayed.
Data reduction is the process of summarising data to characterise the data set succinctly in one or several numerical values.
Making informal inferences
Informal inference arises when students use the sets of data they have collected to make claims about a wider population.
Using different media
The teaching and learning of statistics can be enhanced using various types of media, as wide-ranging as YouTube demonstrations, e-newsletters and statistics in the news.
Although students can consider the separate components of data investigations (data collection, representation, reduction and informal inference), it is essential that they undertake entire investigations.