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10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit
Mean
Median
Mode
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10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit
Remember the key
You can also have back-to-back stem and leaf diagrams
![Page 3: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/3.jpg)
10 .Presenting and analysing data
*Stem and leaf diagrams
Remember the key
You can also have back-to-back stem and leaf diagrams
![Page 4: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/4.jpg)
10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit
The median is not influenced by extreme values
![Page 5: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/5.jpg)
10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit
Lower quartile (LQ):
) n+1/(4 th value
Median:
) n+1/(2 th value
Upper quartile (UQ):
3)n+1/(4 th value
![Page 6: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/6.jpg)
10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit
Range:
Highest value – lowest value
Interquartile range (IQR):
UQ - LQ
![Page 7: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/7.jpg)
10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit
Use a table with a column for fx
![Page 8: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/8.jpg)
10 .Presenting and analysing data
*Averages from frequency distributions
Use a table with a column for fx
![Page 9: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/9.jpg)
10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit
![Page 10: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/10.jpg)
10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit
Use a table with columns for mid-point and fm
![Page 11: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/11.jpg)
10 .Presenting and analysing data
*Averages from grouped dataUse a table with columns for mid-point and fm
![Page 12: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/12.jpg)
10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit
A moving average ‘smooths out’ the data to show the underlying trend
![Page 13: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/13.jpg)
10 .Presenting and analysing data
*Moving averagesA moving average ‘smooths out’ the data to show the underlying trend
![Page 14: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/14.jpg)
10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit
A scatter diagram is used to see if two sets of data are related
![Page 15: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/15.jpg)
10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit
Positive correlation
Zero correlation
Negative correlation
![Page 16: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/16.jpg)
10 .Presenting and analysing data
*Correlation and lines of best fitPositive correlation
Zero correlation
Negative correlation
![Page 17: 10. Presenting and analysing data * Averages for discrete data * Stem and leaf diagrams * Using appropriate averages * The quartiles * Measures of spread](https://reader030.vdocuments.net/reader030/viewer/2022032804/56649e545503460f94b4b5d9/html5/thumbnails/17.jpg)
10 .Presenting and analysing data *Averages for discrete data
*Stem and leaf diagrams
*Using appropriate averages
*The quartiles
*Measures of spread
*Averages from frequency distributions
*Spread from frequency distributions
*Averages from grouped data
*Moving averages
*Scatter diagrams
*Correlation and lines of best fit