Topics covered within this unit: 18·1 Types of data 18·2 Gathering data 18·3 Representing data 18·4 Representing continuous data
18·5 Introduction to statistical investigations
The Learning Outcomes covered in this unit are contained in the following sections:
SP.3a SP.3b SP.3c SP.3d SP.3f ●
Key words Statistics
Data Categorical data Numerical data Nominal data Ordinal data Discrete Continuous Population Census Sample Primary data Secondary data Bias Tally Frequency table Line plot Bar chart Histogram
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Collecting and representing data
Something to think about …
Sara has read that schools in a diff erent country are planning to stop giving students homework. She wants to conduct a survey to fi nd out people’s opinions on homework.
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She decides to survey fi ve of her best friends. Is this a good sample? Justify your answer. Who else could she ask?
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One of the questions on her survey is: ‘Homework is a waste of time; how many hours homework should we get?’
Is this a good question? How could you improve it?
Sara wants to produce a report to give to the school principal. Design a questionnaire she could use to collect reliable data. Who should she ask other than students? Identify the types of data she will collect.
What would be the best way to represent the data she collects in her report to the principal?
18·1 Types of data
By the end of this section you should: ● understand what statistics is and where it is used ● understand that there are diff erent types of data ● be able to classify data
Statistics involves collecting data (information), analysing it (looking for patterns or trends, fi nding averages and spread), representing it (drawing tables and charts) and interpreting it (understanding what it means).
Statistics is a branch of Mathematics that deals with the collection, analysis, representation and interpretation of data.