Inter quartile range
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The document discusses the interquartile range (IQR), which represents the distance between the 25th and 75th percentiles of a data set. It is useful for measuring the spread of rank-ordered or highly skewed data. For rank-ordered data, the IQR indicates the spread between the first and third quartiles. For skewed data, the IQR is more representative of central tendency than the standard deviation since it is not affected by outliers as much.
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Inter quartile range
- 2. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. Interquartile Range
- 3. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. 1 2 3 4 5 6 7 8 9 1 2 3 4 5 Interquartile Range
- 4. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. 1 2 3 4 5 6 7 8 9 1 2 3 4 5 25th percentile Interquartile Range
- 5. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. 50th percentile 1 2 3 4 5 6 7 8 9 1 2 3 4 5 25th percentile Interquartile Range
- 6. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. 50th percentile 1 2 3 4 5 6 7 8 9 1 2 3 4 5 25th percentile This is called the MEDIAN Interquartile Range
- 7. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. 50th percentile 1 2 3 4 5 6 7 8 9 1 2 3 4 5 25th percentile 75th percentile Interquartile Range
- 8. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. 50th percentile 1 2 3 4 5 6 7 8 9 1 2 3 4 5 25th percentile 75th percentile This means that 25% of the scores fall below this point. Interquartile Range
- 9. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. 50th percentile 1 2 3 4 5 6 7 8 9 1 2 3 4 5 25th percentile 75th percentile This means that 25% of the scores fall below this point. This means that 75% of the scores fall below this point. Interquartile Range
- 10. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. 1 2 3 4 5 6 7 8 9 1 2 3 4 5 25th percentile 75th percentile Interquartile Range
- 11. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. 1 2 3 4 5 6 7 8 9 1 2 3 4 5 25th percentile 75th percentile Interquartile Range
- 12. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. 1 2 3 4 5 6 7 8 9 1 2 3 4 5 25th percentile 75th percentile 50% of the scores fall between these two points Interquartile Range
- 13. Interquartile Range The interquartile range represents the distance between the 25th percentile and 75th percentile. 1 2 3 4 5 6 7 8 9 1 2 3 4 5 25th percentile 75th percentile 50% of the scores fall between these two points This is the Interquartile Range! Interquartile Range
- 14. Purposes of the Interquartile Range (IQR) Interquartile Range
- 15. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. Interquartile Range
- 16. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. 1. Rank ordered Data Interquartile Range
- 17. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. 1. Rank ordered Data 9t 8t 7t 7t 5t 6t 6t 5t 4t 6t 5t 5t 3d 2d 1st 1 2 3 4 5 6 7 8 9 1 2 3 4 5 3d4t 4t Interquartile Range
- 18. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. 1. Rank ordered Data 9t 8t 7t 7t 5t 6t 6t 5t 4t 6t 5t 5t 3d 2d 1st 1 2 3 4 5 6 7 8 9 1 2 3 4 5 3d4t 4t First Interquartile Range
- 19. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. 1. Rank ordered Data 9t 8t 7t 7t 5t 6t 6t 5t 4t 6t 5t 5t 3d 2d 1st 1 2 3 4 5 6 7 8 9 1 2 3 4 5 3d4t 4t FirstLast Interquartile Range
- 20. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. 1. Rank ordered Data 2. Highly Skewed Data Interquartile Range
- 21. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. 1. Rank ordered Data 2. Highly Skewed Data 1 2 3 3 5 4 4 5 6 4 5 5 7 7 22 23 1 2 3 4 5 6 7 23 1 2 3 4 5 6 6 22 Interquartile Range
- 22. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. 1. Rank ordered Data 2. Highly Skewed Data 1 2 3 3 5 4 4 5 6 4 5 5 7 7 22 23 1 2 3 4 5 6 7 23 1 2 3 4 5 6 6 22 Mean = 7 Median = 5 Interquartile Range
- 23. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. 1. Rank ordered Data 2. Highly Skewed Data 1 2 3 3 5 4 4 5 6 4 5 5 7 7 22 23 1 2 3 4 5 6 7 23 1 2 3 4 5 6 6 22 IQR Interquartile Range
- 24. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. 1. Rank ordered Data 2. Highly Skewed Data 1 2 3 3 5 4 4 5 6 4 5 5 7 7 22 23 1 2 3 4 5 6 7 23 1 2 3 4 5 6 6 22 IQR Standard Deviation = 5.3 Interquartile Range
- 25. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. 1. Rank ordered Data 2. Highly Skewed Data 1 2 3 3 5 4 4 5 6 4 5 5 7 7 8 9 1 2 3 4 5 6 7 1 2 3 4 5 6 6 IQR 8 9 Standard Deviation = 2.3 Notice how the Standard Deviation drops from 5.3 to 2.3. Interquartile Range
- 26. Purposes of the Interquartile Range (IQR) The Interquartile Range (IQR) is a helpful measure of spread for two scenarios. 1. Rank ordered Data 2. Highly Skewed Data 1 2 3 3 5 4 4 5 6 4 5 5 7 7 8 9 1 2 3 4 5 6 7 1 2 3 4 5 6 6 IQR 8 9 Standard Deviation = 2.3 Notice how the Standard Deviation drops from 5.3 to 2.3. However the IQR stays the same. Interquartile Range