Pearson Median Skewness (Second Skewness) Calculator

Posted by Dinesh on

Skewness, in statistics, is the degree of distortion from the symmetrical bell curve, or normal distribution, in a set of data. Skewness can be negative, positive, zero or undefined. A normal distribution has a skew of zero, while a lognormal distribution, for example, would exhibit some degree of right-skew

  • Skewness, in statistics, is the degree of distortion from the symmetrical bell curve in a probability distribution.
  • Distributions can exhibit right (positive) skewness or left (negative) skewness to varying degree.
  • Investors note skewness when judging a return distribution because it, like kurtosis, considers the extremes of the data set rather than focusing solely on the average.

Skewness can be positive or negative or zero.

  • When the values of mean, median and mode are equal, there is no skewness.
  • When mean > median > mode, skewness will be positive.
  • When mean < median < mode, skewness will be negative.

Characteristic of a good measure of skewness

  • It should be a pure number in the sense that its value should be independent of the unit of the series and also degree of variation in the series.
  • It should have zero-value, when the distribution is symmetrical.

It should have a meaningful scale of measurement so that we could easily interpret the measured value.

Karl-Pearson’s Method (Personian Coefficient of Skewness)

Karl Pearson has suggested two formulas,

  • where the relationship of mean and mode is established;
  • where the relationship between mean and median is not established.

Also Read: Pearson Mode Skewness

This calculator calculates the pearson median skewness using mean, mode, standard deviation values.

Pearson Median Skewness (Second Skewness) Calculation

Formula:

Median skewness = 3 x (x̄ - Mo) ÷ s

Where,

x̄= the mean,
Mo = the mode,
s = the standard deviation for the sample.