Update README.md

README.md

@@ -38,7 +38,13 @@ This is an early test version intended for internal use. However, we are conside
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 ## Quality Tags
-The quality tags are assigned based on percentile ranges of rating scores from various data sources, which are normalized and time-weighted to prioritize recent ratings.
+For quality tags, we evaluated image popularity through the following process: 
+-  Data normalization based on various sources and ratings.
+-  Application of time-based decay coefficients according to date recency.
+-  Ranking of images within the entire dataset based on this processing.
+   
+Our ultimate goal is to ensure that quality tags effectively track user preferences in recent years.
+
 
 | Percentile Range | Quality Tags |
 |:-----------------|:------------------|