Data transformations consist of
1) Square-Root Transformation (this method is used when the average and variance in the sample are proportional)
2) Logarithmic Transformation (this method is used when the average and standard deviation are proportional)
3) Reciprocal Transformation (this method is used when the square average and standard deviation of the sample are proportional)
4) Angular or Inverse Sine Transformation (this method is used when average and variance is proportional and the data set has binomial distribution).