Data Handling Coursework

1
Data Handling Coursework

• 10 of your GCSE

2
Agenda

• What is the coursework?
• The 3 assessment criteria.
• Marking.
• Dates and arrangements.

3
Write down

• This presentation and other important information
  will be available to you either
• on the webwww.rgshw.com/mathscw
• or on the school network O\Mathematics\GCSECours
  ework

4
What is the coursework?

• Mayfield high is a fictious school, but the data
  presented is based on a real school, by means of
  an excel database.
• You are to develop a line of enquiry broken into
  several smaller areas of statistical
  investigation.
• Marking is broken into 3 main areas, which you
  should cover in your investigation.

5
The 3 assessment criteria.

• Strand 1 Specify the problem and plan.
• Strand 2 Collect, process and represent data.
• Strand 3 Interpret and discuss results.
• Each strand is worth 8 marks for a total of 24
  overall.

6
Strand 1 Specify the problem and plan.

• MAIN AIMS
• Decide on a question.
• Split into two or three hypotheses.
• Model the problem mathematically.
• Consider potential problems.
• Decide on constraints.
• Avoid redundancy if you dont need it dont
  include it.

7
Strand 1 Specify the problem and plan.

• Modelling a problem

• Ask the main question.

Main Question Consider the type of data
available Mayfield High Database (Secondary
Data). Level 78 projects may contain primary
data to check validity of secondary data. What is
the main areas you will examine?
Think about related topics to the main
question 2/3 hypotheses should be
made. Correlation of data. Distributions of each
type of data. Differences between age
groups. Differences between sexes.

• Related topics.

People Mayfield High Database gives results for
Years 7, 8, and 9 on the KS3 data sheet and for
Years 10 and 11 on the KS4 data sheet. Is this
representative of the population?

• People

8
Strand 1 Specify the problem and plan.

• Qualitative Data - Lower level marks,
• E.g. Hair colour
• Quantitative Discrete - Mid level marks, E.g. IQ
• Quantitative Continuous - Higher level marks,
  E.g. Height, Mass

9
Strand 1 Specify the problem and plan.

• Secondary Data
• Quicker
• But
• May be errors.
• Data may not be accurate/fair.
• Methods used for collection are not known.

• Primary Data
• Can get exactly data required.
• As accurate/fair as you make it.
• But
• Time consuming.

10
Strand 1 Specify the problem and plan.

• Are peoples height and mass related?
• Is eye colour related to hair colour?
• How far do pupils travel to school?
• What TV programmes do children watch?
• Are peoples height and mass related?

11
Strand 2 Collect, process and represent data.

• MAIN AIMS
• Carry out unbiased sampling, giving reasons for
  sampling techniques chosen.
• Graphs and calculations which are relevant, no
  redundancy.
• Calculations must be shown, Excel is not enough.

12
Strand 2 Collect, process and represent data.

• The Mayfield high database is available on the
  common drive.
• Excel spreadsheet can be saved and modified.
• Or on the web at www.edexcel.org.uk
• Choose GCSE Mathematics
• Choose Link GCSE (Linear) Mathematics A.
• Choose Link Coursework supporting items
• Choose File Mayfield High School Datasheet
  (428KB).
• Excel spreadsheet can be saved and modified.

13
Strand 2 Collect, process and represent data.

• This will employ the use of Excel and Autograph.
• Both are available on the school network.
• Autograph can be downloaded on a 30day trial
  from www.autograph-math.com or google autograph

14
Strand 2 Collect, process and represent data.

• Autograph
• Comparing 2 data distributions
• New Statistics page
• Insert Grouped Data
• Use raw data
• Edit raw data
• Copy in Excel
• Paste into window
• Adjust class intervals
• Name Data
• Right click gt Cumulative Freq. Diagram
• Right click gt Box and Whisker Diagram
• Right click gt Histogram

• Autograph
• Relating 2 sets of data
• New Graph page
• Insert XY Data Set
• Copy in Excel
• Paste into window
• Default Scales
• (See Scatter Graph)
• Right click on point
• Centroid
• Right click on point
• Best fit..

15
Strand 2 Collect, process and represent data.

• GRAPHS
• No graph should be used that does not help to
  prove or disprove one of your hypotheses.
• All graphs should be interpreted.
• You can use computer generated graphs (using
  Autograph), but make sure they are accurate and
  mathematically correct!

• CALCULATIONS
• No calculation should be used that does not help
  to prove or disprove your hypotheses.
• All calculations should be interpreted.
• You can use computer generated calculations
  (using Excel) as long as you can describe what
  has been done and why it is relevant.

16
Strand 3 Interpret and discuss results.

• MAIN AIMS
• Sum up all interpretation so far in concise
  conclusions that answer hypotheses directly.
• Evaluate your results how accurate are they?
• What predictions can be made with what level of
  significance?
• How could the techniques be refined to improve
  accuracy?

17
Strand 3 Interpret and discuss results.

• Evaluation should include
• Give clear ideas for more data that could be
  collected (outside of Mayfield High)
• Choose a further hypothesis that relates to what
  you have done and discuss how you would test it
  or model it.
• If it is possible to make a prediction and check
  it, this will earn a high level in Strand 3.

18
Marking.

• To achieve a Level 7, you dont need to
  satisfy the criteria for levels 1-6!

19
Strand 1 Specify the problem and plan.

• For levels 1 2
• Simple well-defined problem.
• Clear aims.
• Plan is used, but not stated.
• Structure is loosely related to aims.

• For levels 3 4
• Problem involves simple statistical techniques.
• Plan is clearly stated and meets aims.
• Appropriately sized samples are used.

20
Strand 1 Specify the problem and plan.

• For levels 5 6
• A more complex problem relating a number of
  features.
• Plan is well described and meets aims.
• Initial aims may be revised or reviewed.
• Practical problems of data collection are
  addressed.
• Sampling techniques are justified.
• Project is well structured and works as a whole.

21
Strand 1 Specify the problem and plan.

• For levels 7 8
• Problem needs creative thinking and careful
  specification.
• Aims and plan expressed in statistical terms.
• Problems with data collection are foreseen.
• Steps are taken to avoid bias.
• Sampling techniques avoid bias (stratified
  sampling).
• Limitations of sampling method are given.
• Techniques such as control groups and
  pre-sampling are used to refine the project.
• Report is well structured and conclusions relate
  to original aims.

22
Strand 2 Collect, process and represent data.

• For levels 1 2
• Relevant data.
• Simple calculations (mode and range).
• Results are frequently correct!
• Simple graphs (bar chart, pictogram, line graph).
• Analysis relates to overall plan.

• For levels 3 4
• Relevant data collected efficiently.
• Calculations used for comparisons (mode, mean,
  median and range).
• Results are generally correct!
• Graphs have suitable scales and titles (pie
  charts, scatter graphs with best fit lines).
• Statistical vocabulary used.
• Writing interprets diagrams and calculations.

23
Strand 2 Collect, process and represent data.

• For levels 5 6
• Relevant and reliable data.
• Demanding calculations (averages of grouped data,
  IQR).
• Reasons for choices of graphs and calculations
  given.
• Results are correct and no calculations are left
  out.
• Little redundancy.
• Harder graphs (frequency polygons, best fit lines
  through centroid).
• Precise and consistent use of statistical
  analysis.

24
Strand 2 Collect, process and represent data.

• For levels 7 8
• Problems with data are dealt with.
• Results are correct and there is no redundancy.
• Sampling to examine a population is justified.
• Effect on accuracy of sample size is discussed.
• Numerical results are appropriately rounded.
• A convincing, well reasoned argument is produced.
• Histograms are used.
• Analysis relates to overall plan and shows
  interrelation of variables.

25
Strand 3 Interpret and discuss results.

• For levels 1 2
• Comment on data.
• Results are summarised.
• No real links to initial plan.

• For levels 3 4
• Patterns in data discussed.
• Exceptions noticed.
• Graphs and calculations interpreted.
• Conclusions relate to original problem.
• Strategy is evaluated to some extent.

26
Strand 3 Interpret and discuss results.

• For levels 5 6
• Comment on patterns in data.
• Suggest reasons for exceptions to patterns.
• Summarise interpretations of graphs and
  calculations correctly.
• Link summary to initial problem to draw
  inferences.
• Include allowance for sampling method in these
  inferences.
• Discussion of statistical significance of
  results.
• Evaluate strategy and assess limitations.

27
Strand 3 Interpret and discuss results.

• For levels 7 8
• Comment on patterns giving reasons for any
  exceptions.
• Correctly summarise and interpret analysis.
• Significance of results is appreciated.
• Nature of sample is taken into consideration when
  making inferences.
• Effectiveness of method is evaluated.
• Limitations are recognised and improvements
  suggested.
• Constructive comments on the practical
  consequences of work are given.

28
Dates and arrangements

• You will have 2/3 coursework lessons a week,
  mainly in IT rooms.
• Deadline Thursday 9th November, 8.45am,
  collected centrally in room 31.
• If you are ill that day, use parents or DHL
  courier if necessary.

29
TODAY

• Make sure your username and password work if
  not, see Mrs Kirkby/Mr Brant
• Access and download into your user area or home
  PC, the following
• 1. Mayfield High Database
• 2. Candidate Sheet
• 3. This PowerPoint Presentation
• Work out a method for transferring data between
  home school (memory stick/ email/floppy disk)

30
How to succeed.

• Spend time planning and modelling carefully.
• Make sure your plan allows you to show off your
  skills.
• Keep on top of the work week by week.
• Be succinct!

31
Write down

• This presentation and other important information
  will be available to you either
• on the webwww.rgshw.com/mathscw
• or on the school network O\Mathematics\GCSECours
  ework