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In data mining what is a class label..? please give an example

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data-mining

i don't understand what it means. in database a tuple means a field value and a attribute means a table field? am i correct? and what is a Class label in Data Mining?

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Akhil T Mohan Avatar asked Apr 01 '16 17:04

Akhil T Mohan


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What is class label in data mining?

To predict a classification, you must specify the input fields to be classified and the class label field. The class label field is also called target field. The class label field contains the class labels of the classes to which the records in the source data were attributed during the historical classification.

What is the difference between class and label?

Classes and Labels are almost similar things. However, Labels are associated with each and every instance but classes cater to a group of instances within them. To classify something you'll have to label it, so they are similar terms but with different scopes.

What does class mean in data science?

Classification is the process of predicting the class of given data points. Classes are sometimes called as targets/ labels or categories. Classification predictive modeling is the task of approximating a mapping function (f) from input variables (X) to discrete output variables (y).

What is a label in ML?

A label is the thing we're predicting—the y variable in simple linear regression. The label could be the future price of wheat, the kind of animal shown in a picture, the meaning of an audio clip, or just about anything.


3 Answers

Very short answer: class label is the discrete attribute whose value you want to predict based on the values of other attributes. (Do read the rest of the answer.)

The term class label is usually used in the contex of supervised machine learning, and in classification in particular, where one is given a set of examples of the form (attribute values, classLabel) and the goal is to learn a rule that computes the label from the attribute values. The class label always takes on a finite (as opposed to inifinite) number of different values.

For a concrete example, we might be given a set of adult people and we'd like to predict whether they're homeless or not. Suppose the attributes were highest educational level achieved and origin (examples are of the from (origin, educationalLevel; isHomeless):

(Manhattan, PhD; no)
(Brooklyn, Primary school; yes)
...

In this particular case, isHomeless is the class label. The goal is to learn a function that computes whether the person with a given attribute values is homeless or not. (More specifically, to learn a function that makes as little mistakes as possible under a certain quantification of the number of mistakes.)

The Wikipedia article Supervised learning gives a good description.

Regarding the other question: no, a tuple means the whole set of values of the attributes in a given row. For example, if you had a table Table person(id, name, surname) then a tuple representing the first row could be (0, 'Akhil', 'Mohan').

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blazs Avatar answered Sep 30 '22 17:09

blazs


Take an example of email spam filter, it classifies that an email is a spam or not, for which we define 2 classes which are spam(class 1) and not spam(class 2). Both of these are class labels or you can say that, if an email have some certain attributes then it belongs to spam class or not spam class

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Shashwat Pandey Avatar answered Sep 30 '22 15:09

Shashwat Pandey


Basically a class label (in classification) can be compared to a response variable (in regression): a value we want to predict in terms of other (independent) variables.

Difference is that a class labels is usually a discrete/Categorcial variable (eg-Yes-No, 0-1, etc.), whereas a response variable is normally a continuous/real-number variable.

You can find more about Regression and Classification related to Response variables and Class lables at https://math.stackexchange.com/questions/141381/regression-vs-classification.

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Anish Singh Walia Avatar answered Sep 30 '22 17:09

Anish Singh Walia