Update README.md

README.md

@@ -42,10 +42,28 @@ This dataset is a combination of the following datasets:
 
 The main purpose is to collect the large data into one place for easy training and evaluation.
 
-The full datasets were shuffled and randomly split into `train` and `test` splits.
+## Data Preparation and Transformation
+
+### Quality Score Normalization
+
+The dataset was enhanced with additional columns, and quality scores (n = 909 533) were normalized using Ordered Quantile normalization through the `bestNormalize` package in R. This transformation mapped original values to a standardized normal distribution, resulting in a new variable, `transformed_quality`, included in both training and test datasets to enhance statistical modeling capabilities.
+
+### Readability Score Calculation
+
+U.S. reading grade levels were transformed using the Box-Cox method (`bestNormalize` package) with λ = 0.8766912. A custom function standardized the results and inverted the scale to generate 'readability' scores, where higher values indicate easier readability.
+
+The standardized Box-Cox transformation was applied to 919 663 non-missing observations, yielding the following statistics:
+
+- λ (lambda) = 0.8766912
+- Mean (before standardization) = 7.908629
+- Standard deviation (before standardization) = 3.339119
+
+These transformations improved the dataset's suitability for subsequent statistical analyses.
 
 ## Dataset size
 
+The full datasets were shuffled and randomly split into `train` and `test` splits.
+
 | Dataset | Train split | Test split |
 |---------|-------------|------------|
 | quality       | 809 533     | 100 000    |