# EEG Sleep Stages Classification Based on Time Domain Features and Structural Graph Similarity(2016)
- ### Abstract
- The proposed model uses graph theory and extracts the features from EEG and uses K-Means algorithm to classify the sleep stages.
- ### Model
- The model classifies EEG into 6 sleep stages(RK method).
- Each segment(sleep epoch) of EEG signal is broken down to m sub segments, whose features are extracted and mapped to a graph.
- THe structural similarity properties are extracted and put into a classifier.
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- The 12 key features to represent the graph are median, mazimum, minimum, mean, mode, range, first qaurtile, second quartile, standard deviation, variation, skewness, kurtosis.
- The features extracted are degree distribution, clustering coefficient andJaccard similarity coefficient.
- K-means clustering algorithm used for classification.
- ### Evaluation
- The dataset used was Sleepedf.
- Evaluation was done taking top 6, top 10 and all 12 features from the graph as mentioned above.
- Classifaction based on 12 features gave the best result with an accuracy of 95.15%.