Class Prediction Task

A Class Prediction Task is a nominal prediction task whose mapping set is a finite class set.

• AKA: Categorization, Categorical Label Assignment.
• Context:
  • Input: an item (often a data item); and a class set.
    • optional input: a classification function structure; or a training set.
  • output: one or more class set members (possibly as Class Member Identifiers).
    • optional output: a classification function structure.
  • measures: e.g. Classification Accuracy.
    • optional measures: Precision, Recall, F1, ROC Curve for binary classification.
  • It can range from being a Binary Classification Task to being a Multiclass Classification Task (such as large multiclass classification), depending on the Class Set size.
  • It can range from being a Unilabel Classification Task to being a Multilabel Classification Task, depending on the number of class outputs,.
  • It can range from being a Simple-Input Classification Task to being a Complex-Input Classification Task, depending on the complexity of the input item.
  • It can range from being a Model-based Classification Task to being ...
  • It can range from being a Manual Classification Task to being an Automated Classification Task.
  • It can range from being a Heuristic Classification Task to being a Data-Driven Classification Task (such as a supervised classification), depending on whether some uncertainty is allowed in the decision.
  • It can range from being a Probabilistic Classification Task to being ...
  • It can range from being a Batch Classification Task to being an Online Classification Task.
  • It can be solved by a Classification System (that implements a classification algorithm).
  • It can be instantiated as a Classification Act.
  • It can (often) be a Data Classification Task.
  • …
• Example(s):
  • a Text Item Classification Task.
  • an Image Classification Task.
  • a Complex Input Classification Task, such as: Part-of-Speech Tagging, or Text Chunking.
  • a Rules-based Classification Task, such as: Given the Classification Model IF X is human THEN X is mortal. what is the class membership of X=Socrates?
  • a Biological Specific Classification.
  • Given the Patient Record p, classify whether the patient should or should not be given aspirin.
  • Guess the outcome of a Card Draw Experiment based on your intuition
  • Guess the outcome of a Card Draw Experiment based on Data of the coin's past performance
  • Guess whether Customer [math]\displaystyle{ X }[/math] will not pay their current bill by its due date, based on your intuition.
  • Guess whether Customer [math]\displaystyle{ X }[/math] will not pay their current bill by its due date based on Data of the customer and other customer's past performance.
  • …
• Counter-Example(s):
  • any Ordinal Prediction Task.
  • any Numeric Prediction Task.
  • an Item Scoring Task.
  • a Point Estimation Task.
  • a Complex Output Decisioning Task.
  • a Face Recognition Task?
  • a Clustering Task.
• See: Class, Cost-Benefit Matrix, Loss Function, Scientific Classification, Join Operation.

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References

2011

• (Drummond, 2011c) ⇒ Chris Drummond. (2011). “Classification.” In: (Sammut & Webb, 2011) p.168

2009

• (Wikipedia, 2009) ⇒ http://en.wikipedia.org/wiki/Classification_(biology)
  • Biological classification or scientific classification in biology, is a method by which biologists group and categorize species of organisms. Biological classification is a form of scientific taxonomy, but should be distinguished from folk taxonomy, which lacks scientific basis. …

2009

• (Wikipedia, 2009) ⇒ http://en.wikipedia.org/wiki/Classification_(literature)
  • Classification is a figure of speech linking a proper noun to a common noun using the or other articles.

2009

• http://wordnet.princeton.edu/perl/webwn
  • categorization: the act of distributing things into classes or categories of the same type
  • a group of people or things arranged by class or category
  • restriction imposed by the government on documents or weapons that are available only to certain authorized people

2009

• http://en.wiktionary.org/wiki/classification
  • The act of forming into a class or classes; a distribution into groups, as classes, orders, families, etc. …

2009

• http://wordnet.princeton.edu/perl/webwn
  • arrange or order by classes or categories; "How would you classify these pottery shards--are they prehistoric?"
  • declare unavailable, as for security reasons; "Classify these documents"
  • relegate: assign to a class or kind; "How should algae be classified?"; "People argue about how to relegate certain mushrooms"

2009

• http://en.wiktionary.org/wiki/classify
  • to identify by or divide into classes; to categorize; to declare something a secret, especially a government secret

2009

• (Hand, 2009) ⇒ David J. Hand. (2009). “Mismatched Models, Wrong Results, and Dreadful Decisions: On Choosing Appropriate Data Mining Tools.” In: Proceedings of the 15th ACM SIGKDD International Conference on Knowledge Discovery and Data Mining (KDD-2009). doi:10.1145/1557019.1557021
  • QUOTE: For predictive classification problems, a wide variety of score functions exist, including measures such as precision and recall, the F measure, misclassification rate, the area under the ROC curve (the AUC), and others.

1986

• (Quinlan, 1986a) ⇒ J. Ross Quinlan. (1986). “Induction of Tecision Trees." Machine Learning, 1(1).
  • QUOTE: … Examples of classification tasks are: Page 3. … It might appear that classification tasks are only a minuscule subset of procedural tasks, but even activities such as robot planning can be recast as classification problems (Dechter and Michie, 1985). …

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