GCSE MATHS Data handling

Data Handling Pose a question There are 4 steps to data handling. We call it the cycle. Pose a question Decide on the data and collect Organise and Analyse Interpret and draw results

For example What is the question? I think that when rolling a dice, a 6 will occur less times than it should What should you do to collect the data? How will we organise our results? What did our results tell us?

Problems People who smoke die young - Your question can be too vague…. For instance…. People who smoke die young How do you define people who smoke? Is it someone who smokes once a year? If they stopped smoking do they get removed from your test? Define young. Am I young? Are you? We need a more exact question such as: People who smoke at least more than 1 a day die before they reach pension age (65)

Primary Secondary Collecting data There are 2 types of data. Primary Secondary Data you collect ie. A survey or by observing Data you get from somewhere else ie. The internet or timetable

Exercises - discuss

Types of data There are 3 types of data Quantative – The data is counted ie a number Qualitative – The data is described in words Quantitative – The data is measured

Data collection We usually collect data in a table. More usually it is called a frequency table. And we use tally marks to count our numbers. They are grouped in 5’s and 5 is called a gate (for obvious reasons)

EXERCISE I will pose a question. The letter E is the most common letter in each person in the classes First Name. What steps will we take to see if this is correct?

Grouped data

Be careful! Some data is called continuous when it doesn’t always fall on a round number! Examples of this are when measuring height or weight. You usually record this data differently

Two way tables

Answers: 7 c. 14 2 d. 31

Good practice guidelines! QUestionnaires A good source of primary data can be questionnaires. Good practice guidelines! The simpler the question, the easier it is to answer. IE Yes / No questions Give a choice of answers rather than leaving them open ended IE tickboxes Make sure your responses do not overlap or leave gaps that aren’t covered Never ask personal questions. People are less likely to answer them.

sampling When carrying out a survey it sometimes is too time consuming to ask everyone involved. For example, what is the most popular name in the college? Instead we ask a ‘sample’ of students. And we need to make sure we obtain a representative sample. This is a sample which will give the fairest and balanced range of peoples opinions.

Foundation tier

HIGHER TIER EXAMPLE