handling data 1

Handling data 1

BTEOTSSSBAT:Identify quantitative and qualitative data

Display data using bar charts, pie charts and stem and leaf diagrams

Key wordsDiscreteContinuousStem and leaf diagramdatapictogrampie chartbar charttallyfrequency

Types of data

Statistics is a branch of mathematics that is concerned with the collection and interpretation of data.There are different types of data:

Data

Types of data

Statistics is a branch of mathematics that is concerned with the collection and interpretation of data.There are different types of data:

Data

QuantitativeQualitative

Types of data

Statistics is a branch of mathematics that is concerned with the collection and interpretation of data.There are different types of data:

Data

QuantitativeQualitative

Continuous‘measured’

Discrete‘counted’

Now try these 1State whether each of the following is qualitative or quantitative data. If quantitative, state whether it is discrete or continuous.

(a) The number of pupils in a class.(b) The colour of cars in a car park.(c) The time spent by a motorist waiting at a red traffic light.(d) The styles of women’s dresses available in a chain store.(e) The number of votes received by the candidates in an election.(f) The club of each of the members of the England football team.(g) The number of players from a club who play football for England.(h) The mass of a new born baby.(i) The number of words on a page of a book.(j) The duration of a hockey match.

Collecting data

Name Transport Time (mins)1

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8

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Transport Tally Frequency

PictogramA pictogram is a very simple-to-read way of presenting data. It is cheerful and it makes a powerful visual impact.

Bar ChartThe bar chart is easier to draw than a pictogram and allows for greater accuracy. It is best drawn on graph paper.

0

2

4

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12

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16F

req

uen

cy

Sh irt Co lour

How to draw pie charts

Step 1

Put the information in a table

Eye colour No of people

Blue 5

Green 2

Hazel 2

Grey 1

Total 10

How to draw pie charts

Step 1

Put the information in a table

Eye colour No of people

Blue 5

Green 2

Hazel 2

Grey 1

Total 10

How to draw pie charts

Step 1

Put the information in a table

Step 2

Work out how many degrees for one item360º represent 10 peopleSo 360º ÷ 10 = 36º

36º represent 1 person

Eye colour No of people

Blue 5

Green 2

Hazel 2

Grey 1

Total 10

How to draw pie charts

Step 1

Put the information in a table

Step 2

Work out how many degrees for one item360º represent 10 peopleSo 360º ÷ 10 = 36º

36º represent 1 person

No of degrees

5 x 36º = 180º

2 x 36º = 72º

2 x 36º = 72º

1 x 36º = 36º

360º

Step 3 Write down in the table how many degrees for each item.

How to draw pie charts

Step 5

Draw a circle and draw on the correct angles

How to draw pie charts

Step 5

Draw a circle and draw on the correct angles

Step 6

Label the segments

Grey eyes

Blue eyes

Green eyes

Hazel eyes

Stem and leaf diagramsStem and leaf diagrams are also known as stemplots. They are useful ways of displaying information.

ExampleThese are the results for a module test for 10 students:12 23 34 35 37 55 56 57 68 68

10 220 330 4 5 74050 5 6 760 8 8

We can display this on a stem and leaf diagram.

LeavesStem

Stem and leaf diagramsStem and leaf diagrams are also known as stemplots. They are useful ways of displaying information.

ExampleThese are the results for a module test for 10 students:12 23 34 35 37 55 56 57 68 68

1 22 33 4 5 745 5 6 76 8 8

Stem and leaf diagramsStem and leaf diagrams are also known as stemplots. They are useful ways of displaying information.

ExampleThese are the results for a module test for 10 students:12 23 34 35 37 55 56 57 68 68

1 22 33 4 5 745 5 6 76 8 8

L = 12lowest

Stem and leaf diagramsStem and leaf diagrams are also known as stemplots. They are useful ways of displaying information.

ExampleThese are the results for a module test for 10 students:12 23 34 35 37 55 56 57 68 68

1 22 33 4 5 745 5 6 76 8 8

L = 12

H = 68

Stem and leaf diagramsStem and leaf diagrams are also known as stemplots. They are useful ways of displaying information.

ExampleThese are the results for a module test for 10 students:12 23 34 35 37 55 56 57 68 68

1 22 33 4 5 745 5 6 76 8 8

n = 12

L = 12

H = 71

Stem and leaf diagramsStem and leaf diagrams are also known as stemplots. They are useful ways of displaying information.

ExampleThese are the results for a module test for 10 students:12 23 34 35 37 55 56 57 68 68

1 22 33 4 5 745 5 6 76 8 8

3 3 represents 33 marks

n = 12

L = 12

H = 71

A key

Stem and leaf diagramsStem and leaf diagrams are also known as stemplots. They are useful ways of displaying information.

ExampleThese are the results for a module test for 10 students:12 23 34 35 37 55 56 57 68 68