Page 103 - Data Science Algorithms in a Week

Random Forest

We have the following variable available ['Sunshine']. As there are fewer of them than
the parameter m=4, we consider all of them. Of these, the variable with the highest
information gain is the variable Sunshine. Therefore, we will branch the node further on
this variable. We also remove this variable from the list of the available variables for the
children of the current node. For the chosen variable Sunshine, all the remaining features
have the same value: Sunny. So, we end the branch with a leaf node. We add the leaf node
[Play=Yes].

We add a child node [Wind=Strong] to the node [Temperature=Warm]. This branch
classifies two feature(s): [['Warm', 'Strong', 'Cloudy', 'No'], ['Warm',
'Strong', 'Cloudy', 'No']]
We would like to add children to the node [Wind=Strong].

We have the following variable available ['Sunshine']. As there are fewer of them than
the parameter m=4, we consider all of them. Of these, the variable with the highest
information gain is the variable: Sunshine. Therefore, we will branch the node further on
this variable. We also remove this variable from the list of the available variables for the
children of the current node. For the chosen variable Sunshine, all the remaining features
have the same value: Cloudy. So, we end the branch with a leaf node. We add the leaf node
[Play=No].

Now, we have added all the children nodes for the node [Temperature=Warm].

We add a child node [Temperature=Hot] to the node [root]. This branch classifies three
feature(s): [['Hot', 'Breeze', 'Cloudy', 'Yes'], ['Hot', 'Breeze',
'Cloudy', 'Yes'], ['Hot', 'Breeze', 'Cloudy', 'Yes']]

We would like to add children to the node [Temperature=Hot].

We have the following variables available ['Wind', 'Sunshine']. As there are fewer of
them than the parameter m=4, we consider all of them. Of these, the variable with the
highest information gain is the variable Wind. Therefore, we will branch the node further
on this variable. We also remove this variable from the list of the available variables for the
children of the current node. For the chosen variable Wind, all the remaining features have
the same value: Breeze. So, we end the branch with a leaf node. We add the leaf node
[Play=Yes].

Now, we have added all the children nodes for the node [root].

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