STATISTICAL TECHNIQUES AND TOOLS
MEASURE OF STANDARD DEVIATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It uses only two entries from the data set.
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It uses all entries from the data set.
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It is easy to compute.
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None of the above
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Detailed explanation-1: -The range is the difference between the largest and the smallest observation in the data. The prime advantage of this measure of dispersion is that it is easy to calculate. On the other hand, it has lot of disadvantages. It is very sensitive to outliers and does not use all the observations in a data set.
Detailed explanation-2: -Unlike the previous measures of variability, the variance includes all values in the calculation by comparing each value to the mean.
Detailed explanation-3: -The interquartile range is the best measure of variability for skewed distributions or data sets with outliers. Because it’s based on values that come from the middle half of the distribution, it’s unlikely to be influenced by outliers.