Exam-Style Problems

Stage 9 - Q1 - 4 marks

20177

Plot a scatter graph for the paired data. Describe the relationship.

x

1

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4

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6

7

8

y

21

28

33

34

39

41

48

52

Hint

Keep the two values from each column together.

Stage 9 - Q2 - 3 marks

20178

Describe the direction and strength of the association in the scatter graph.

y

0

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6

7

8

9

10

0

20

40

60

80

100

x

Hint

Direction and strength are different features.

Stage 9 - Q3 - 3 marks

20179

Describe the direction and strength of the association in the scatter graph.

y

0

1

2

3

4

5

6

7

8

9

10

0

20

40

60

80

100

x

Hint

Direction and strength are different features.

Stage 9 - Q4 - 3 marks

20180

Describe the direction and strength of the association in the scatter graph.

y

0

1

2

3

4

5

6

7

8

9

10

0

20

40

60

80

100

x

Hint

Direction and strength are different features.

Stage 9 - Q5 - 4 marks

20181

These fictional data pair weekly practice hours x with a skill score y. The graph is positive. Does it prove that additional practice caused every increase in score?

y

0

1

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4

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6

7

8

9

10

0

20

40

60

80

100

x

Hint

Ask whether other explanations have been ruled out.

Stage 9 - Q6 - 4 marks

20182

One point sits far below the main trend. Should it automatically be deleted before discussing the relationship? Explain a sensible next step.

y

0

1

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8

9

10

0

20

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60

80

100

x

Hint

An unusual value can be a real observation.

Stage 9 - Q7 - 4 marks

20183

These fictional data pair weekly practice hours x with a skill score y. The graph is positive. Does it prove that additional practice caused every increase in score?

y

0

1

2

3

4

5

6

7

8

9

10

0

20

40

60

80

100

x

Hint

Ask whether other explanations have been ruled out.

Stage 9 - Q8 - 4 marks

20184

One point sits far below the main trend. Should it automatically be deleted before discussing the relationship? Explain a sensible next step.

y

0

1

2

3

4

5

6

7

8

9

10

0

20

40

60

80

100

x

Hint

An unusual value can be a real observation.

Stage 9 - Q9 - 4 marks

20185

These fictional data pair weekly practice hours x with a skill score y. The graph is positive. Does it prove that additional practice caused every increase in score?

y

0

1

2

3

4

5

6

7

8

9

10

0

20

40

60

80

100

x

Hint

Ask whether other explanations have been ruled out.

Stage 9 - Q10 - 6 marks

20186

The paired readings come from machine types A and B. Describe the association in each type and in the pooled data. Explain why the pooled trend should not be used alone to claim that increasing x raises y for either machine type.

Response y

0

1

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8

0

10

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40

50

Setting x

A

B

Hint

Follow the points within each labelled group before considering all six together.