“…Supervised learning techniques that have been used for spam review detection so far are; Rule based classification [5,10], Unified model [2], Logistic Regression [4,11,12], Knearest neighbor (KNN) [4], Random Forest [4,[13][14][15], Decision Trees [16,17], Gradient Decent [4,10], Genetic Algorithm [18], Conceptual Model [19], Time Series [20], Neural Network [21], Deep Neural Network [22], Multinomial Naïve Bayes [9,11,13], N-Gram [13], Hybrid Learning Approach (Active and supervised learning) [23], RNN, CNN [24], and Multilayer Perceptron Model (MLP) [4,24], Unsupervised learning is a category of machine learning that work on the unlabeled datasets. Many unsupervised learning techniques have been used in spam detection which are: Natural Language Processing [6,9][58] Markov Network [25], Neural Auto-encoder Decision Forest [16]¸ and PU Learning [26]. Other than these supervised and unsupervised learning techniques, there are many other techniques that have been used for spam detection such as Fuzzy Logic [27], Heterogeneous Information Network [28], Hadoop [29], Text Mining [30], Sentiment Analysis [31][32][33][34]<...>…”