Keystroke_GMM.py

#keystroke_GMM.py

from sklearn.mixture import GMM
import pandas
from EER_GMM import evaluateEER
import numpy as np
import warnings
warnings.filterwarnings("ignore")

class GMMDetector:
#the training(), testing() and evaluateEER() function change, rest all is same.

    def __init__(self, subjects):
        self.user_scores = []
        self.imposter_scores = []
        self.mean_vector = []
        self.subjects = subjects

    def training(self):
        self.gmm = GMM(n_components = 2, covariance_type = 'diag',
                        verbose = False )
        self.gmm.fit(self.train)

    def testing(self):
        for i in range(self.test_genuine.shape[0]):
            j = self.test_genuine.iloc[i].values
            cur_score = self.gmm.score([j])
            self.user_scores.append(cur_score)

        for i in range(self.test_imposter.shape[0]):
            j = self.test_imposter.iloc[i].values
            cur_score = self.gmm.score([j])
            self.imposter_scores.append(cur_score)

    def evaluate(self):
        eers = []

        for subject in subjects:
            genuine_user_data = data.loc[data.subject == subject, \
                                         "H.period":"H.Return"]
            imposter_data = data.loc[data.subject != subject, :]

            self.train = genuine_user_data[:200]
            self.test_genuine = genuine_user_data[200:]
            self.test_imposter = imposter_data.groupby("subject"). \
                                 head(5).loc[:, "H.period":"H.Return"]

            self.training()
            self.testing()
            eers.append(evaluateEER(self.user_scores, \
                                     self.imposter_scores))
        return np.mean(eers)

path = os.path.dirname( os.path.realpath(__file__) )
data_path = os.path.join(path, 'keystroke.csv')
data = pandas.read_csv(data_path)
subjects = data["subject"].unique()
print "average EER for GMM detector:"
print(GMMDetector(subjects).evaluate())