Label Classification Problem Research Articles

Efficient ensembles of distance‐based label ranking trees

AbstractEnsemble of label ranking trees (LRTs) are currently the state‐of‐the‐art approaches to the label ranking problem. Recently, bagging, boosting, and random forest methods have been proposed, all based on the LRT algorithm, which adapts regression/classification trees to the label classification problem. The LRT algorithm uses theoretically grounded Mallows probability distribution to select the best split when growing the tree, and an EM‐type process to complete the rankings on the training data when they are incomplete. These two steps have proven to be accurate, but require a large computational effort. This article proposes two alternative methods that replace the use of the Mallows distribution with distance‐based criteria to select the best split at each inner node of the tree. Moreover, these distance‐based criteria allow dealing with incomplete rankings natively, so avoiding the completion process. We have carried out an extensive experimental evaluation, which shows that (1) the integration of the two proposed modifications to the LRT algorithm into ensemble methods (bagging and random forest) are an order of magnitude faster than using the original Mallows‐based LRT algorithm; (2) ensembles using the proposed LRT methods are significantly more accurate in the presence of incomplete rankings, while they are at least as accurate in the complete case; and (3) the two modified LRT algorithms are also an order of magnitude faster than the Mallows‐based LRT, while they are at least as accurate as the Mallows‐based LRT on both complete and incomplete rankings.

A Multilabel Classifier for Text Classification and Enhanced BERT System

Now-a-day, a vast variety of reviews are published on the web. As a result, an automated system to analyze and extract knowledge from such textual data is needed. Sentiment analysis is a well-known sub-area in Natural Language Processing (NLP). In earlier research, sentiments were determined without considering the aspects specified in a review instance. Aspect-based sentiment analysis (ABSA) has caught the attention of researchers. Many existing systems consider ABSA as a single label classification problem. This drawback is handled in this study by proposing three approaches that use multilabel classifiers for classification. In the first approach, the performance of a model with hybrid features is analyzed using the multilabel classifier. The hybrid feature set includes word dependency rule-based features and unigram features selected using the proposed two-phase weighted correlation feature selection (WCFS) approach. In the second and third approaches Bidirectional Encoder Representation from Transformers (BERT) language model is used. In the second approach, a BERT system is enhanced by applying max pooling on target terms which specify an aspect of a review instance and a multibit label is given as input to the BERT system. In the third approach, the basic BERT system is used for word embedding only and classification is done using multilabel classifiers. In all approaches, the label used for all training instances specifies aspects with its sentiments. The experimentation shows that the results gained using the system proposed in the first approach are comparable to the results gained using the BERT system. The experimental results depict that the Enhanced BERT system gives better results compared to the existing systems.

An intelligent work order classification model for government service based on multi-label neural network

The classification of work orders for livelihood service play an important role in the e-government system, which goal is to push these work orders to the corresponding processing department. Although many studies have realized the classification of work orders automatically, these work orders are either related to many subjects or related to many departments. Therefore, the problem of work order classification is not a single label classification problem, but a multi-label classification problem. In view of the continuous development of deep neural networks, the goal of this paper is to modify a MultilabelMarginLoss function and design a MultilabelCrossEntropyLoss function to realize the multi-classification system of work orders, which can push the work orders to the related departments(one or more departments) automatically according to their appeal contents (consisting of short texts). We perform deep neural network for text classification including TextCNN, TextRCNN, TextRNN, TextRNN_Att, FastText and DPCNN on the real government hotline data set and compare the performances of these models. The results reveal that TextCNN and TextRCNN have a more stable performance on different loss functions, especially on the MultilabelCrossEntropyLoss function.

Target curricula via selection of minimum feature sets

We consider the effect of introducing a curriculum of targets when training Boolean models on supervised Multi Label Classification (MLC) problems. In particular, we consider how to order targets i...

A Multi-Label Classification Approach Based on Correlations Among Labels

Multi label classification is concerned with learning from a set of instances that are associated with a set of labels, that is, an instance could be associated with multiple labels at the same time. This task occurs frequently in application areas like text categorization, multimedia classification, bioinformatics, protein function classification and semantic scene classification. Current multi-label classification methods could be divided into two categories. The first is called problem transformation methods, which transform multi-label classification problem into single label classification problem, and then apply any single label classifier to solve the problem. The second category is called algorithm adaptation methods, which adapt an existing single label classification algorithm to handle multi-label data. In this paper, we propose a multi-label classification approach based on correlations among labels that use both problem transformation methods and algorithm adaptation methods. The approach begins with transforming multi-label dataset into a single label dataset using least frequent label criteria, and then applies the PART algorithm on the transformed dataset. The output of the approach is multi-labels rules. The approach also tries to get benefit from positive correlations among labels using predictive Apriori algorithm. The proposed approach has been evaluated using two multi-label datasets named (Emotions and Yeast) and three evaluation measures (Accuracy, Hamming Loss, and Harmonic Mean). The experiments showed that the proposed approach has a fair accuracy in comparison to other related methods.

PROJECTING AWAY THE CLASS IMBALANCE PROBLEM IN AUTHOR ATTRIBUTION

Author identification algorithms attempt to ascribe document to author, with an eye towards diverse application areas including: forensic evidence, authenticating communications, and intelligence gathering. We view author identification as a single label classification problem, where 2000 authors would imply 2000 possible categories to assign to a post. Experiments with a naive Bayes classifier on a blog author identification task demonstrate a remarkable tendency to over-predict the most prolific authors. Literature search confirms that the class imbalance phenomenon is a challenge for author identification as well as other machine learning tasks. We develop a vector projection method to remove this hazard, and achieve a 63% improvement in accuracy over the baseline on the same task. Our method adds no additional asymptotic computational complexity to naive Bayes, and has no free parameters to set. The projection technique will likely prove useful for other natural language tasks exhibiting class imbalance.