Sample Augmentation method explain
Three methods are available to generate synthetic samples : Replicate, Jitter and SMOTE
Replicate
This is the simplest method. N new samples are generated by duplicating N samples already present in the sample set.
Jitter
New samples are generated by adding gaussian noise to input samples which are randomly selected with replacement.
SMOTE
This section summarizes the SMOTE algorithm using an illustration. The fully explanation about the SMOTE method used in iota2 is available here.
The figure below shows the generation of one sample using 3 neighbors:
SMOTE algorithm
These 4 steps are repeated to generate as many samples as needed. Thanks to the use of neighbors, noise generation is less important than the jitter method. The higher the number of neighbors, the lower the noise.