Statistics Practical: Kurtosis and Skewness (TU BBA 3rd Semester)

Learning Objectives

• To calculate Kurtosis and Skewness in Microsoft Excel [With Video Tutorial]

Calculate Kurtosis and Skewness from the given data in Excel.

Range	f
0-10	1
10-20	7
20-30	14
30-40	7
40-50	1

Formula Recalling:

Kurtosis = (Quartile Deviation)/(P90 -P10)=(Q3 -Q1)/2(P90-P10)

Skewness =(Mean -Mode)/Standard deviation (σ)

Step 1

Calculating quatile 1 (Q1), quartile 3 (Q3), P10, P90, Mean, Mode, and Standard Deviation

Quartile 1 and Quartile 3

Quartile 1
Q1 item	7.5	=(D17/4)
Q1 class	10-20
Q1	19.286	=B13+(B20-F12)/D13*(C13-B13)
Quartile 3
Q3 item	22.5
Q3 class	30-40
Q3	30.714	=B15+(B25-F14)/D15*(C15-B15)

Source: Excel 2013

Percentile 10 and Percentile 90

Percentile 10
P10 item	3
P10 class	10-20
P10	12.86	=B13+(E20-F12)/D13*(C13-B13)
Percentile 90
P90 item	27
P90 class	30-40
P90	37.14	=B15+(E25-F14)/D15*(C15-B15)

Source: Excel 2013

Mean, Standard Deviation, and Mode

Model calculation

Model Class	20-30	[Highest frequency class]
Mode	25	=L+((f(1)-f(0))/(2*f(1)-f(0)-f(2)))*(C14-B14)

Source: Excel 2013

Mean	25
SD	8.5635

To know the calculation procedure of mean and standard deviation, click here.

Step 2

Calculating Kurtosis

Kurtosis

0.2353

=(Q3-Q1)/(2*(P90-P10))

Source: Excel 2013

Calculating Skewness

Sk

0

=(Mean-Mode)/Standard Deviation

Source: Excel 2013

Conclusion

we follow two steps in calculating skewness and kurtosis.

For more clarification, watch our video tutorial