MullOverThings

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# What is the training error of the decision tree?

## What is the training error of the decision tree?

There are two error rates to be considered: training error (i.e. fraction of mistakes made on the training set) • testing error (i.e. fraction of mistakes made on the testing set) The error curves are as follows: tree size vs. training error tree size vs.

## What is the training error rate for the tree?

We see the tree has 7 terminal nodes, a training error rate of 15.8%.

## What are decision trees explain ID3 algorithm along with an example?

In simple words, a decision tree is a structure that contains nodes (rectangular boxes) and edges(arrows) and is built from a dataset (table of columns representing features/attributes and rows corresponds to records).

## What is ID3 algorithm in machine learning?

In decision tree learning, ID3 (Iterative Dichotomiser 3) is an algorithm invented by Ross Quinlan used to generate a decision tree from a dataset. ID3 is the precursor to the C4. 5 algorithm, and is typically used in the machine learning and natural language processing domains.

## What is the difference between test error and training error?

It is very important to understand the difference between a training error and a test error. Remember that the training error is calculated by using the same data for training the model and calculating its error rate. For calculating the test error, you are using completely disjoint data sets for both tasks.

## Can a decision tree classify an entire training set with zero errors?

A decision tree trained on a training data set would only have no errors in classification if: You allowed your tree to have an infinite number of splits.

## How do you calculate training set error?

Remember that the training error is calculated by using the same data for training the model and calculating its error rate. For calculating the test error, you are using completely disjoint data sets for both tasks.

## What are the steps in ID3 algorithm?

The steps in ID3 algorithm are as follows:

1. Calculate entropy for dataset.
2. For each attribute/feature. 2.1. Calculate entropy for all its categorical values. 2.2. Calculate information gain for the feature.
3. Find the feature with maximum information gain.
4. Repeat it until we get the desired tree.

## What is the advantage of ID3 algorithm?

Some major benefits of ID3 are: Understandable prediction rules are created from the training data. Builds a short tree in relatively small time. It only needs to test enough attributes until all data is classified.

## Can the training error be zero?

Zero training error is impossible in general, because of Bayes error (think: two points in your training data are identical except for the label).