# Blog

## How is information gain calculated?

Information Gain is calculated for a split by subtracting the weighted entropies of each branch from the original entropy. When training a Decision Tree using these metrics, the best split is chosen by maximizing Information Gain.Jun 7, 2019

## Why do we calculate information gain?

Information gain calculates the reduction in entropy or surprise from transforming a dataset in some way. ... Information gain is the reduction in entropy or surprise by transforming a dataset and is often used in training decision trees.Oct 16, 2019

## What is information gain of attribute?

Then the information gain of for attribute is the difference between the a priori Shannon entropy of the training set and the conditional entropy . The mutual information is equal to the total entropy for an attribute if for each of the attribute values a unique classification can be made for the result attribute.

## How do you calculate entropy and gain?

We simply subtract the entropy of Y given X from the entropy of just Y to calculate the reduction of uncertainty about Y given an additional piece of information X about Y. This is called Information Gain. The greater the reduction in this uncertainty, the more information is gained about Y from X.

## How is a decision tree pruned?

We can prune our decision tree by using information gain in both post-pruning and pre-pruning. In pre-pruning, we check whether information gain at a particular node is greater than minimum gain. In post-pruning, we prune the subtrees with the least information gain until we reach a desired number of leaves.

## What is information gain in data mining?

Data Mining - Information Gain

Information gain is the amount of information that's gained by knowing the value of the attribute, which is the entropy of the distribution before the split minus the entropy of the distribution after it.

## What is gain ratio in data mining?

Gain Ratio is modification of information gain that reduces its bias. Gain ratio overcomes the problem with information gain by taking into account the number of branches that would result before making the split.It corrects information gain by taking the intrinsic information of a split into account.Jul 10, 2018

## What is information gain and entropy?

The information gain is the amount of information gained about a random variable or signal from observing another random variable. Entropy is the average rate at which information is produced by a stochastic source of data, Or, it is a measure of the uncertainty associated with a random variable.

## What is mutual information I X Y?

In classical information theory, the mutual information of two random variables is a quantity that measures the mutual dependence of the two variables. Intuitively, the mutual information "I(X:Y)" measures the information about X that is shared by Y.Oct 26, 2015

### How do you find the gain in Python?

Partition the dataset based on unique values of the descriptive feature. Compute impurity for each partition. Compute the remaining impurity as the weighted sum of impurity of each partition. Compute the information gain as the difference between the impurity of the target feature and the remaining impurity.

### Can information gain be more than 1?

Yes, it does have an upper bound, but not 1. The mutual information (in bits) is 1 when two parties (statistically) share one bit of information. However, they can share a arbitrary large data. In particular, if they share 2 bits, then it is 2.

### What are Gini's coefficient and information gain?

Summary: The Gini Index is calculated by subtracting the sum of the squared probabilities of each class from one. It favors larger partitions. Information Gain multiplies the probability of the class times the log (base=2) of that class probability.Feb 27, 2016

### What is information gain and entropy?

• Information Gain as a concept is commonly used in decision trees as a measure for determining the relevance of a particular variable. In simple terms, it refers to the gain in information or reduction in entropy when a variable is conditioned on another variable.

### How do you calculate net capital gain?

• Your net capital gain/loss is calculated by subtracting your capital losses from your capital gains (Schedule D). If you have a net capital loss, you're allowed to deduct up to \$3,000 (\$1,500 if married filing separately) per year as a capital loss. If your net capital loss is more than the yearly limit,...

### How do you calculate a capital gain or loss?

• To calculate your capital gains or losses on a particular trade, subtract your basis from your net proceeds. The net proceeds equal the amount you received after paying any expenses of the sale. For example, if you sell stock for \$3,624, but you paid a \$12 commission, your net proceeds are \$3,612.