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Questions tagged [gini-index]

For questions related to the Gini index, or Gini coefficient, or Gini impurity

The Gini index, or Gini coefficient, or Gini impurity computes the degree of probability of a specific variable that is wrongly being classified when chosen randomly and a variation of the Gini coefficient. It works on categorical variables, provides outcomes either be "successful" or "failure" and hence conducts binary splitting only.

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When should I use Gini Impurity as opposed to Information Gain (Entropy)?

Can someone practically explain the rationale behind Gini impurity vs Information gain (based on Entropy)? Which metric is better to use in different scenarios while using decision trees?
Krish Mahajan
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What is the meaning of the Gini Index?

I'm studying random forest models, but I don't understand what the Gini index is and what it's for. Does anyone have any material on this or can give me an explanation? Thanks!
Inuraghe
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Decision tree Why is Gini index only used for binary choices?

I would like to understand why "Gini index operates on the categorical target variables in terms of “success” or “failure” and performs only binary split" ? Why it would not be possible to have 3 decision after a split when we are using the Giny…
Edouard99
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Value[] attribute in my decision tree is not consistent with number of samples

I read that value[] attribute in a decision tree shows the distribution of the samples across class 1 and class 2. However, my value[] is not adding up. In the root node for example, there are 14 samples and the value=[10.0,10.0]. Some nodes have a…
Dharmini
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Model/variable gini?

I'm working with a colleague concurrently between R and MS Excel looking at credit risk scorecard modelling. In Excel he has calculated what he says is the gini coefficient for certain variables, which he has calculated by ranking the variable from…
StMatthias
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How to find significance for Gini coefficient changes?

I'm using the Gini coefficient to evaluate the performance of a model. Making some changes (feature selection, hyperparameter tuning, etc.) I created variant models with different Gini coefficients. How can I prove that the improvement in the Gini…
Lafayette
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How to compute the Gini index, the entropy and the classification error from a decision tree?

How to find the Gini index, the entropy, and the classification error for each node of the tree in the figure below. Please help me to compute them.
Nezuko
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