Information is not sufficient to find mean deviation and standard deviation.
advantages of quartile deviation
What is mean deviation and why is quartile deviation better than mean deviation?
If this is the only information you have, the answer would be somewhere around 125. Usually, you would find the third quartile by first finding the median. Then find the median of all of the numbers between the median and the largest number, which is the third quartile.
Q3-q1
Information is not sufficient to find mean deviation and standard deviation.
What is coefficient of quartile deviation?
advantages of quartile deviation
mean deviation =(4/5)quartile deviation
Strictly speaking, none. A quartile deviation is a quick and easy method to get a measure of the spread which takes account of only some of the data. The standard deviation is a detailed measure which uses all the data. Also, because the standard deviation uses all the observations it can be unduly influenced by any outliers in the data. On the other hand, because the quartile deviation ignores the smallest 25% and the largest 25% of of the observations, there are no outliers.
What is mean deviation and why is quartile deviation better than mean deviation?
In a data sample, the purpose of quartile deviation is a way to measure data dispersion instead of using the range. The quartile deviation is found by subtracting the lower quartile from the upper quartile, and dividing this result by two.
If this is the only information you have, the answer would be somewhere around 125. Usually, you would find the third quartile by first finding the median. Then find the median of all of the numbers between the median and the largest number, which is the third quartile.
coefficient of quartile deviation: (Q3-Q1)/(Q3+Q1)
Square the standard deviation and you will have the variance.
Quartile Deviation (QD)The quartile deviation is half the difference between the upper and lower quartiles in a distribution. It is a measure of the spread through the middle half of a distribution. It can be useful because it is not influenced by extremely high or extremely low scores. Quartile Deviation is an ordinal statistic and is most often used in conjunction with the median.why we calculating quartile deviation?
You need more than one number to calculate a standard deviation, so 9 does not have a standard deviation.