Study Comparison Backpropogation, Support Vector Machine, and Extreme Learning Machine for Bioinformatics Data
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Jurnal Ilmu Komputer dan Informasi (Journal of Computer Science and Information). 8/1 (2015), 53-59 DOI: http://dx.doi.org/10.21609/jiki.v8i1.284 STUDY COMPARISON BACKPROPOGATION, SUPPORT VECTOR MACHINE, AND EXTREME LEARNING MACHINE FOR BIOINFORMATICS DATA Umi Mahdiyah1, M. Isa Irawan1, and Elly Matul Imah2 1Faculty of Mathematics and Science, Institut Teknologi Sepuluh Nopember, Jl. Arief Rahman Hakim, Surabaya, 60111, Indonesia 2 Mathematics Department, Universitas Negeri Surabaya, Jl. Ketintang, Surabaya, 60231, Indonesia E-mail: [email protected] Abstract A successful understanding on how to make computers learn would open up many new uses of computers and new levels of competence and customization. A detailed understanding on inform- ation- processing algorithms for machine learning might lead to a better understanding of human learning abilities and disabilities. There are many type of machine learning that we know, which includes Backpropagation (BP), Extreme Learning Machine (ELM), and Support Vector Machine (SVM). This research uses five data that have several characteristics. The result of this research is all the three investigated models offer comparable classification accuracies. This research has three type conclusions, the best performance in accuracy is BP, the best performance in stability is SVM and the best performance in CPU time is ELM for bioinformatics data. Keywords: Machine Learning, Backpropagation, Extreme Learning Machine, Support Vector Machine, Bioinformatics Abstrak Keberhasilan pemahaman tentang bagaimana membuat komputer belajar akan membuka banyak manfaat baru dari komputer. Sebuah pemahaman yang rinci tentang algoritma pengolahan informasi untuk pembelajaran mesin dapat membuat pemahaman yang sebaik kemampuan belajar manusia. Banyak jenis pembelajaran mesin yang kita tahu, beberapa diantaranya adalah Backpropagation (BP), Extreme Learning Machine (ELM), dan Support Vector Machine (SVM). Penelitian ini menggunakan lima data yang memiliki beberapa karakteristik. Hasil penelitian ini, dari ketiga model yang diamati memberikan akurasi klasifikasi yang sebanding. Penelitian ini memiliki tiga kesimpulan, yang terbaik dalam akurasi adalah BP, yang terbaik dalam stabilitas adalah SVM dan CPU time terbaik adalah ELM untuk data bioinformatika. Kata Kunci: Machine Learning, Backpropagation, Extreme Learning Machine, Support Vector Machine, Bioinformatika 1. Introduction gradient descent type algorithm, which has con- nection parameter for each step or iteration. But, A successful understanding of how to make com- this algorithm can provide harmony result bet- puters learn would open up many new uses of ween "network capability" to recognize the pat- computers and new levels of competence and cus- terns which used for training and "network capa- tomization. And a detailed understanding of infor- bility" to respond correctly to the input patterns mation-processing algorithms for machine learn- that similar (but not equal) to the training pattern. ing might lead to a better understanding of human Then, Backpropagation algorithm has limit classi- learning abilities (and disabilities) as well [1]. fication accuracy, because if the output value is Many type of machine learning that we know, so- different from the target value, an error will be me of them are Backpropagation (BP), Extreme calculated, and then taken from the output layer to Learning Machine (ELM), and Support Vector the input layer (Backpropagation process). Machine (SVM). Until now, many researchers have developed First Machine Learning is backpropagation. and implemented the BP algorithm [3-7]. Imple- Backpropagation was initially formulated by We- mentation BP for classification was implemented bros in 1974, which was later modified by Rumel- in most problem as bioinformatics, biomedical, hart and McClelland [2]. Backpropagation is the chemistry, art, environment, etc. Several research 53 54 Jurnal Ilmu Komputer dan Informasi (Journal of Computer Science and Information), Volume 8, Issue 1, February 2015 use this algorithm because BP has minimum error 2. Methods and effective for some problem, especially in this study for classification problem. Backpropagation The next powerful machine learning is Sup- port Vector Machines (SVM). Support vector ma- Backpropagation is one of many supervised ma- chines (SVM) are a group of supervised learning chine learning. Backpropagation is the gradient methods that can be applied to classification or re- descent type algorithm .This algorithm has two gression. This Machine learning is different from phases for processing data. First phase, input vec- Machine Learning in ANN. In SVM when train- tor given to input layer, continued to hidden layer ing process, SVM isn’t training all data, but this then finding output value in output layer. Second algorithm just training support vector data. Based phase, if the output value is different from the tar- idea from this algorithm is optimization margin get value, an error will be calculated, and then ta- hyper plane. Although SVM need big memory ken from the output layer to the input layer (Back- and need long time to process data, but many re- propagation process) [19]. searcher use SVM to solve some problem [8-11], In BP, transfer function must fulfill several because this machine learning have high perfor- conditions: continue differentiable, not descend- mance. ing function. In this paper we use sigmoid binary Extreme Learning Machine is one of a new function as defined in equation(1) and its deriva- learning algorithm in neural networks, which has tion as in equation(2). the Single-hidden Layer feed-forward Network (SLFN). ELM has a very fast learning capability 1 ( ) = (1) and training small error [12]. First ELM was in- 1 + troduced by Huang in 2004 as Single-hidden Lay- − er Feed-forward Network. ELM was made to ov- ( ) = ( ) 1 ( ) (2) ercome the weaknesses of the feed-forward neural ′ networks problem that learning speed. Tradition- Backpropagati on training � − follow � these step ally, feed-forward neural network using gradient- [20]: a) Initialize neuron’s weight with random based learning algorithm for training, as well as number. all the parameters (input weight and hidden bias) Forward propagation are determined by iterative network, to solve that b) Each input layer neuron receives the inputs and problem, Extreme Learning Machine using mini- passes it to the connected hidden layer’s neuron. mum norm least-squares (LS) solution of SLFNs. c) Compute output value from hidden layer , = Unlike the traditional function approximation 1,2 … , , with the weight is that connected theories which require to adjusted input weights input layer and hidden layer using equation(3) and and hidden layer biases, input weights and hidden equation(4) . layer biases can be randomly assigned if only the activation function is infinitely differentiable [13]. So, ELM can be faster than prior the neural net- = + (3) work algorithm previously. ELM has been applied and developed in various fields [14-18]. Up until 0 � now this algorithm is developed, the main reason =1 1 many research use this algorithm because this al- = = (4) 1 + gorithm is simple and faster than several algori- − thm in ANN. � � If the hidden layer end, we continue to output lay- In this paper, we will compare three algori- er. d) Compute all output values from output layer thm for classification several bioinformatics data as equation(5) and equation(6). that have some criteria. Dataset was taken from UCI Machine Learning. We use general BP, SVM using linear kernel and general ELM. We choose = + (5) Backpropagation (BP), Extreme Learning Machi- ne (ELM), and Support Vector Machine (SVM) 0 � because that all machine learning have good per- =1 1 = ( _ ) = (6) formance for classification [2-18]. The rest of the 1 + _ paper is organized as follows. In Section 2, we − present the detail of BP, SVM, and ELM. Follow- Backpropagation ing that, Section 3 provides experimental results e) Compute the output layer’s error factor based and discussions. Finally, we draw conclusions in on the error in each of the output layer’s neuron Section 4. using equation(7) and equation(8). Umi Mahdiyah, et al., Study Comparison Backpropagation 55 TABLE 1 Forward propagation KERNEL FUNCTION Kernel Function 1 1 y 1 Linear ( , ) = . Polynomial ( , ) = ( . + ) 2 x1 1 y2 2 …. …. Gaussian RBF ( , ) = exp 2. 2 x i 3 −‖ −‖ 2 k yk Sigmoid(tangent (, ) = �( ( . )2+ �) …. hyperbolic) ℎ 1 xn n j l yn Multiquadratic ( , ) = Invers | | + w ij 2 wjk 2 m �� − � Back propagation m Figure 1. Backpropagation architecture. _ = ( ) (7) Positive margin w.xi+b=1 ′ =− _ � � (8) Negative margin Hyperplane f) Compute the ∆hidden layer’s∝ error factor based w.xi+b=-1 w.xi+b=0 on error in each of the hidden layer’s neuron using equation(9) to equation(11). Negative class Positive class Figure 2. Margin hyperplane SVM. _ = (9) classes can be obtained, that called linear hyper � plane classifiers [21]. =1 _ = _ ( _ ) (10) This is step of support vector machine algo- rithm: Given training data set D and q feature of = ′_ (11) each data, there are , such that formulated in eq- uation(14) and equation(15). g) The last step count∆ all∝ change of weight of neu- Φ rons using equation(12) and equation(13). : (14) ( ) = ( ) + (12) Φ →( ) (15) ( ) = ( ) + ∆ (13) Where r is new feature set →Φ that result from map- ping D. while x is training data, which , , …, is