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| Mean Deviation |
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| The mean deviation of a statistical data is defined as the arithmetic mean of the numerical values of the deviations of items from some average value. |
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| Mean deviation is also known as average deviation. |
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| The mean deviation is generally denoted by M.D. |
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| Formula for mean deviation for ungrouped data or an individual series is given by |
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| For a frequency distribution, the formula for mean deviation is given by |
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| where M.D is the Mean Deviation and A.M is the Arithmetic Mean. |
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| Example 1: |
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| Find the mean deviation from the mean for the given raw data |
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| 12,6,7,3,15,10,18,5. |
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| Suggested answer: |
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| Example 2: |
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| Calculate the mean deviation from the mean for the following frequency distribution. |
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| Suggested answer: |
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| Let us first find the mean of the given data by step deviation method. |
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| A = Assumed mean = 57.5, h = 5 |
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| \ M = 52 |
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| Mean deviation from the mean |
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