Anomaly detection: Difference between revisions

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* Length of the text message
* Length of the text message
* NULL or empty value
* NULL or empty value
* Minor differences of text content
* Minor differences of text content<ref>[https://medium.com/@ahmetmnirkocaman/how-to-measure-text-similarity-a-comprehensive-guide-6c6f24fc01fe How to Measure Text Similarity: A Comprehensive Guide | by Ahmet Münir Kocaman | Medium]</ref>
* Character encoding e.g. [[Fix garbled message text]]
* Character encoding e.g. [[Fix garbled message text]]


More on: [https://en.wikipedia.org/wiki/Outlier#Identifying_outliers Outlier - Wikipedia]
More on: [https://en.wikipedia.org/wiki/Outlier#Identifying_outliers Outlier - Wikipedia]


[[Category: Data_hygiene]]
== References ==
<references />
 
[[Category: Data hygiene]]
[[Category: Data Science]]
[[Category: Data Science]]

Revision as of 17:01, 15 January 2025

Outlier / Anomaly detection

Anomaly detection of numeric data

  • Median
  • Range Checks
  • All values is event or odd
  • The values are the same even the column is totally different

Anomaly detection of categorical data (qualitative variable)

  • Normal distribution e.g. The interest of audiences should be very different NOT coherent

Anomaly detection for time series data

  • Trend
  • Dramatically Increase or decrease of rows count for each time period

Anomaly detection for consumer data

For consumer data

  • Season issue: consumption data of coat should increase in cold weather
  • Holiday issue: consumption data of some gift e.g. moon cake should increase in special holiday e.g. Mid-Autumn Festival

Anomaly detection for string data

  • Created time of the text message
  • Time frequency of the text message
  • Length of the text message
  • NULL or empty value
  • Minor differences of text content[1]
  • Character encoding e.g. Fix garbled message text

More on: Outlier - Wikipedia

References