METHODS OF DATA ANALYSIS
MEASURES OF DISPERSION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Histogram
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Bar chart
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Ogive
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Polygon
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Detailed explanation-1: -The lower quartile is (n+1)/4 th value (n is the cumulative frequency, i.e. 157 in this case) and the upper quartile is the 3(n+1)/4 the value. The difference between these two is the interquartile range (IQR).
Detailed explanation-2: -To find the interquartile range (IQR), first find the median (middle value) of the lower and upper half of the data. These values are quartile 1 (Q1) and quartile 3 (Q3). The IQR is the difference between Q3 and Q1.
Detailed explanation-3: -The interquartile range is the upper quartile – the lower quartile, so for this data the interquartile range is 47 – 38 = 9.
Detailed explanation-4: -The interquartile range formula for grouped data is the same as with non-grouped data, with IQR being equal to the value of the first quartile subtracted from the value of the third quartile.