The Nottingham Emmanuel School Mathematics Department 18 January 2016 Lesson Objectives (WALT) Learn about different types of data Find out how data can be used to test hypotheses Key Words Quantitative Discrete Primary Data Types of Data Qualitative Continuous Secondary Hypothesis

The Nottingham Emmanuel School Mathematics Department 18 January 2016 Types of Data Primary data information you collect yourself, by asking people, measuring, carrying out experiments, and so on Secondary data information that has been collected already, that you get from books, the internet, and so on

The Nottingham Emmanuel School Mathematics Department 18 January 2016 Data can be either: numerical or quantitative data non-numerical or qualitative data Data can be either: numerical or quantitative data non-numerical or qualitative data Types of Data Some examples of quantitative data: heights time age Some examples of qualitative data: opinions favourite football teams eye colour gender

The Nottingham Emmanuel School Mathematics Department 18 January 2016 Measuring Data Shoe size The number of goals in a football match The temperature of a classroom The time taken to complete 100 metres at the olympics The number of GCSE grade A*s achieved in school last year The number of marks gained in a dance exam The height of a mountain Numerical data can be either: continuous discrete Numerical data can be either: continuous discrete Which of the examples of numerical data given below would need to be rounded off?

The Nottingham Emmanuel School Mathematics Department 18 January 2016 Discrete data jumps from one measurement to the next. The measurements in between have no meaning. Shoe size You can have a shoe size of 4 or 4½ but not 4¼. Number of goals in a football match You can score 2 goals but not 2.5. The number of GCSE grade A*s achieved in your school last year There could have been 40 or 41 A* grades but not The number of marks gained in a dance exam You could get 60 but not 60.8 in the exam. Discrete Data

The Nottingham Emmanuel School Mathematics Department 18 January 2016 Continuous data does not jump from one measurement to the next, but passes smoothly through all the measurements in between. The temperature of a classroom The temperature could be 21 o C, 21.1 o C, o C or …. The time taken to complete a task The time could be 57 secs, 57.1 secs, secs or …. The height of a mountain The height could be 300 m, m, feet, or ….. Continuous Data

The Nottingham Emmanuel School Mathematics Department 18 January 2016 Primary – data you collect yourself Secondary – data collected by someone else Quantitative – numerical values (height, weight) Qualitative – non-numerical (types of car, colour) Discrete – can be measured exactly (pages, people) Continuous – can always find a more accurate measure (height, weight) Types of Data

The Nottingham Emmanuel School Mathematics Department 18 January 2016 Why collect data? Statisticians collect data to test a hypothesis. A hypothesis is a statement of something that may or may not be true, but is thought to be true. For example: Boys are taller than girls. Girls are cleverer than boys. China is bigger than the USA. Nottingham is bigger than New York. Different sorts of data can be collected to test whether the hypothesis is true.