Classification algorithm in machine learning

F-1 Score
F-1 Score is the harmonic mean of Precision and Recall. This gives equal weight to type I and type II errors. The formula is as follows:

When positive and negative targets are unevenly distributed in the data set The F-1 Score is one of the most accurate measurements.
Use cases of classification algorithms.
Classification algorithms can be used in different places. Below are some popular use cases of classification algorithms:

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  Detect email spam
  
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  Speech recognition
  
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  Detection of cancer tumor cells.
  
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  Classification of drugs
  
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  Biometric identification etc.