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6.4 Collecting data

3 These are the masses, to the nearest kilogram, of 24 members of an athletics club.
66 72 88 52 64 85 68 86 75 82 56 61
78 58 62 75 84 62 81 55 95 67 74 63
a Record this information on a data-collection sheet.
b Write down one conclusion that you can make from the results on your data-collection sheet.

For questions 4 and 5, work in groups of three or four.

4 Choose a topic and carry out a survey of the students in your class.
Make sure the topic of your survey does not refer to something that you need to measure
(continuous data). For example, you could ask how students travel to school, the colour of their
eyes, their favourite drink or what football team they support.
a Write down the question you will ask the students in your class.
b Design a data-collection sheet for your survey.
c Carry out the survey and complete your data-collection sheet.
d Write down one conclusion that you can make from the results of your survey.
5 Choose a topic and carry out a survey of the students in your class.
Make sure the topic of your survey does refer to something that you need to measure
(continuous data). For example, you might investigate students’ heights, how far they can reach in
a standing jump, how far up a wall they can reach, the masses of their bags or the time it takes for
them to write out the 8-times table.
a Write down the question you are going to ask the students in your class.
b Design a data-collection sheet for your survey.
c Carry out the survey and complete your data-collection sheet.
d Write down one conclusion that you can make from the results of your survey.

Summary

You should now know that: You should be able to:
+ When you carry out a statistical investigation, + Suggest a question to explore, using statistical

the first thing to do is decide on a hypothesis. methods; identify the sets of data needed, how
A hypothesis is a statement that you think may to collect them, sample sizes and degree of
be true. accuracy.
+ Primary data is data that you collect yourself. + Identify primary or secondary sources of suitable
+ Secondary data is data that has already been data.
collected by someone else. + Design, trial and refine data-collection sheets.

+ A data-collection sheet usually has three columns, + Collect and make a table of discrete and
one for listing the different categories, one for continuous data, choosing suitable equal class
tally marks and one for the total number of tallies. intervals where appropriate.
This is the frequency.
+ When you are grouping data you should use equal
class intervals. Look at all the values the data can
take before you decide whether to group the data.

62 6 Planning and collecting data