SVM Flashcards
Maximum Margin Classifier/Separator
The decision boundary that maximizes separation boundary between separable classes
Soft Margin
In SVC, the amount of error allowed when determining the width of the ‘street’.
The parameter is controlled by C in sklearn
SVC Kernels
How the SVC/SVM transforms the data to create the hyperplane for separating the data
Linear Kernel
No data transformation to determine the decision boundary in SVM/SVC
Non linear kernel
Transformation of the data into a higher number of dimensions to determine the hyperplane that separates the classes
When do you use non linear kernel in SVM
When the data is intermediate (either in number of samples or number of features). When features or samples are large, then the non linear kernel may be predictive but not very performant.
Polynomial Kernel
Polynomial transformation of the data into higher number of dimensions in SVM
Radial Basis Function (RBF) Kernel
Closest observations for a particular datapoint has a lot more weight to classify the current datapoint compared to observations that are further away.
Gamma Parameter (SVM)
In RBF Kernel, this parameter scales the squared distances between two datapoints to determine how much influence nearest datapoints have on the classification of current point.
Higher gamma = More influence the two datapoints have on each other
Support Vectors
Data points closest to the decision boundary that have the greatest influence on the position of the hyperplane
SVM in 1 Sentence
A classification method that uses a hyperplane on higher dimensional transformed data to separate classes