Rating Matrix Research Articles

Closed-Form Models of Accuracy Loss due to Subsampling in SVD Collaborative Filtering

We postulate and analyze a nonlinear subsampling accuracy loss (SSAL) model based on the root mean square error (RMSE) and two SSAL models based on the mean square error (MSE), suggested by extensive preliminary simulations. The SSAL models predict accuracy loss in terms of subsampling parameters like the fraction of users dropped (FUD) and the fraction of items dropped (FID). We seek to investigate whether the models depend on the characteristics of the dataset in a constant way across datasets when using the SVD collaborative filtering (CF) algorithm. The dataset characteristics considered include various densities of the rating matrix and the numbers of users and items. Extensive simulations and rigorous regression analysis led to empirical symmetrical SSAL models in terms of FID and FUD whose coefficients depend only on the data characteristics. The SSAL models came out to be multi-linear in terms of odds ratios of dropping a user (or an item) vs. not dropping it. Moreover, one MSE deterioration model turned out to be linear in the FID and FUD odds where their interaction term has a zero coefficient. Most importantly, the models are constant in the sense that they are written in closed-form using the considered data characteristics (densities and numbers of users and items). The models are validated through extensive simulations based on 850 synthetically generated primary (pre-subsampling) matrices derived from the 25M MovieLens dataset. Nearly 460 000 subsampled rating matrices were then simulated and subjected to the singular value decomposition (SVD) CF algorithm. Further validation was conducted using the 1M MovieLens and the Yahoo! Music Rating datasets. The models were constant and significant across all 3 datasets.

Penerapan Konsep Peringkat Risiko pada Manajemen Risiko Hukum di Perbankan Syariah

This study aims to look at the risk rating, the risk rating is the final conclusion on the Bank's risk after considering the mitigation carried out through the implementation of risk management, to determine the bank's risk rating refers to the rating matrix. This matrix basically maps out risk ratings resulting from a combination of inherent risk and quality of risk management implementation. Research results determine the risk rating because the determination of the rating assessment is the basis for banks to categorize bank risk ratings. The results of applying risk ratings for banks are categorized into five ratings, namely, Low to moderate, Moderate, Moderate to high High, Low.

Dual-path recommendation algorithm based on CNN and attention-enhanced LSTM

ABSTRACT To recommend useful information to users more efficiently, this paper proposes a dual-path recommendation algorithm which combines multilayer Convolutional Neural Network (CNN) and attention-enhanced long short-term memory network (Attention-LSTM). Firstly, the matrix factorisation technique is used for learning the long-term preferences of users. Secondly, a dual-path network based on CNN and LSTM is constructed to perform feature extraction on the rating matrix. The dual-path network can learn the long-term preferences of users while capturing their dynamic preferences in changing preferences. The algorithm is tested on the public dataset MovieLens-1M, and the MAE value reflects the accuracy of the algorithm.

Dynamic context management in context-aware recommender systems

Context-aware recommendation is an essential part of advanced advertising systems. Most of the existing context-aware recommender systems (CARS) build recommendation models considering context as a static entity. In practice, user preferences are dynamic and change over time. In this study, we argue that CARS must be able to dynamically opt for the evolving behavior of contextual attributes. We propose a solution with a runtime identification of contextual information and jointly integrate content analysis to boost recommendation performance. Initially, the proposed model constructs a list of contextually similar candidates. The users’ context information extracted in the initial step is modeled together with the content information to estimate a context score used to find contextually reliable neighbors. Instead of relying on a fixed rating matrix, we dynamically exploit contextual information for effective rating prediction. Experiments on three real-world datasets demonstrate that our method outperforms classical and state-of-the-art recommendation algorithms.

TeSP-TMF: A temporal-aware personalized POI recommendation approach based on potential preferences and grey relational analysis

The great advances in mobile devices make it critical to exploit multiple auxiliary information for efficient point-of-interest (POI) recommendations. However, most existing methods can neither effectively address the extreme data sparsity encountered in temporal-aware recommendation nor reasonably deal with implicit feedback. Furthermore, previous methods, including those relying on similarity measurement, cannot capture the intrinsic data correlations exhibited in the sparse data. To remedy these drawbacks, this paper proposes a temporal-aware personalized recommendation framework called Temporal Spatial Popularity and Temporal-aware Matrix Factorization (TeSP-TMF). In TeSP-TMF, we present the potential preferences model and temporal-aware matrix factorization model. Specifically, users’ potential preferences that incorporate temporal, spatial, and popularity information are investigated to learn a set of potential POIs for each user, which are filled into the original matrix for further matrix factorization, owing to the sparse nature of the rating matrix. On this basis, we develop a new approach using a combination of grey relational analysis and matrix factorization, which not only relieves data scarcity caused by dividing the matrix with time slots but also strategically mines inherent temporal relationships. Finally, we implement extensive experiments on two public datasets collected from Foursquare and Yelp. Experimental results demonstrate that our proposed method yields competitive quality compared to several state-of-the-art methods. Theoretically, our work contributes promising insights for mitigating data sparsity. In practice, our results can enhance personalized temporal-aware POI recommendation services for location-based social networks.

An improved constrained Bayesian probabilistic matrix factorization algorithm

Given the increasing growth of the Web and consequently the growth of e-commerce, the application of recommendation systems becomes more and more extensive. A good recommendation algorithm can provide a better user experience. In the collaborative filtering algorithm recommendation system, many existing approaches to collaborative filtering can neither handle very large datasets nor easily deal with users who have very few ratings, this paper proposes an improved constrained Bayesian probability matrix factorization algorithm. The algorithm introduces a potential similarity constraint matrix for specific sparsely scored users to affect the user’s feature vector, and uses the Logistic function to express the nonlinear relationship of the potential factors, combined with the Markov chain Monte Carlo method for training. Finally, the data set is used for testing and comparative evaluation. This experiment proves that the algorithmic model can be efficiently trained using Markov chain Monte Carlo methods by applying them to the MovieLens and Netflix dataset. The experimental results show that the algorithm has better predictive performance and is suitable for solving the problem of sparse rating matrix of specific users.

Hybrid Movie Recommendation System Using Machine Learning

This research suggests a hybrid movie recommendation system and optimization approach based on weighted classification and user collaborative filtering algorithm to address the issue that the single model of the standard recommendation system cannot adequately reflect user preferences. The top-N personalized movie recommendations are made by fusing the weighted classification model with the local recommendation model, which is trained based on user clustering, and the sparse linear model, which serves as the fundamental recommendation model. The scoring matrix is transformed into a low-dimensional, dense item category preference matrix based on item category preference, multiple cluster centers are obtained, the distance between each cluster center and the target user is calculated, and the target user is categorized into the closest cluster. Finally, a suggestion list is created using the collaborative filtering algorithm to forecast the scores for the target user's unrated items. The highdimensional rating matrix is transformed into a lowdimensional item category preference matrix, which further reduces the sparsity of the data. The items are then grouped based on item category preference. The recommendation algorithm suggested in this article addresses some of the limitations of a single algorithm model and enhances the suggestion effect, according to experiments using the MovieLens movie dataset.

A New Mechanism for Detecting Shilling Attacks in Recommender Systems Based on Social Network Analysis and Gaussian Rough Neural Network with Emotional Learning

A recommender system is an integral part of any e-commerce site. Shilling attacks are among essential challenges in recommender systems, which use the creation of fake profiles in the system and biased rating of items, causing the accuracy to decrease and the correct performance of the recommender system in providing recommendations to users. The target of attackers is to change the rank of content or items corresponded to their interests. Shilling attacks are a threat to the credibility of recommender systems. Therefore, detecting shilling attacks it necessary to in recommender systems to maintain their fairness and validity. Appropriate algorithms and methods have been so far presented to detect shilling attacks. However, some of these methods either examine the rating matrix from a single point of view or use low-order interactions or high-order interactions. This study aimed to propose a mechanism using users' rating matrix, rating time, and social network analysis output of users' profiles by Gaussian-Rough neural network to simultaneously use low-order and high-order interactions to detect shilling attacks. Finally, several experiments were conducted with three models: mean attack, random attack, and bandwagon attack, and compared with PCA, Semi, BAY, and XGB methods using precision, recall, and F1-Measure. The results indicated that the proposed method is more effective than the comparison methods regarding attack detection and overall detection, which proves the effectiveness of the proposed method.

Recommendation System Based on Deep Sentiment Analysis and Matrix Factorization

In order to solve the problem of data sparsity and credibility in collaborative filtering, a recommendation system based on sentiment analysis and matrix factorization (SAMF) is proposed in this paper, which uses topic model and deep learning technology to fully mine the implicit information in reviews to improve the rating matrix and assist recommendation. Firstly, user topic distribution and item topic distribution are generated from reviews(consisting user reviews and item reviews) through LDA(Latent Dirichlet Allocation). The user feature matrix and item feature matrix are created based on topic probability. Secondly, user feature matrix and item feature matrix are integrated to create user-item preference matrix. Thirdly, the user-item preference matrix and the original rating matrix are integrated to create the user-item rating matrix. Fourthly, BERT(Bidirectional Encoder Representation from Transformers) is used to quantify the sentiment information contained in the reviews and integrate the sentiment information with the user-item rating matrix, to modify and update the user-item rating matrix. Finally, the updated user-item rating matrix is used to achieve rating prediction and Top-N recommendation. Experiments on Amazon datasets demonstrates that the proposed SAMF has better recommendation performance than other classical algorithms.

Recommendation System Based on Double Ensemble Models using KNN-MF

In today's digital environment, recommendation systems are essential as they provide personalised content to users, increasing user engagement and enhancing user satisfaction. This paper proposes a double ensemble recommendation model that combines two collaborative filtering algorithms, K Nearest Neighbour (KNN) and Matrix Factorization (MF). KNN is a neighbourhood-based algorithm that uses the similarity between users or items to make recommendations. At the same time, MF is a model-based algorithm that decomposes the user-item rating matrix into lower-dimensional matrices representing the latent user and item factors. The proposed double ensemble model uses KNN and MF to predict missing ratings matrix and combines their predictions using stacking. To evaluate the performance of the proposed ensemble model, we conducted experiments on three datasets i.e. Movielense, BookCrossing dataset and Hindi Movie dataset and compared the results with those of single algorithm approaches. The experimental results demonstrate that the double ensemble model outperforms the single algorithm approaches regarding accuracy metrics such as Mean Square Error (MSE), Root Mean Squared Error (RMSE), Mean Absolute Error (MAE). The results indicate that stacked KNN and MF lead to a more robust and more accurate recommendation system.

Quality standards and recommendations for research in music and neuroplasticity.

Research on how music influences brain plasticity has gained momentum in recent years. Considering, however, the nonuniform methodological standards implemented, the findings end up being nonreplicable and less generalizable. To address the need for a standardized baseline of research quality, we gathered all the studies in the music and neuroplasticity field in 2019 and appraised their methodological rigor systematically and critically. The aim was to provide a preliminary and, at the minimum, acceptable quality threshold-and, ipso facto, suggested recommendations-whereupon further discussion and development may take place. Quality appraisal was performed on 89 articles by three independent raters, following a standardized scoring system. The raters' scoring was cross-referenced following an inter-rater reliability measure, and further studied by performing multiple ratings comparisons and matrix analyses. The results for methodological quality were at a quite good level (quantitative articles: mean = 0.737, SD = 0.084; qualitative articles: mean = 0.677, SD = 0.144), following a moderate but statistically significant level of agreement between the raters (W = 0.44, χ2 = 117.249, p = 0.020). We conclude that the standards for implementation and reporting are of high quality; however, certain improvements are needed to reach the stringent levels presumed for such an influential interdisciplinary scientific field.

Multi-Feature Extension via Semi-Autoencoder for Personalized Recommendation

Over the past few years, personalized recommendation systems aim to address the problem of information overload to help users achieve useful information and make quick decisions. Recently, due to the benefits of effective representation learning and no labeled data requirements, autoencoder-based models have commonly been used in recommendation systems. Nonetheless, auxiliary information that can effectively enlarge the feature space is always scarce. Moreover, most existing methods ignore the hidden relations between extended features, which significantly affects the recommendation accuracy. To handle these problems, we propose a Multi-Feature extension method via a Semi-AutoEncoder for personalized recommendation (MFSAE). First, we extract auxiliary information from DBpedia as feature extensions of items. Second, we leverage the LSI model to learn hidden relations on top of item features and embed them into low-dimensional feature vectors. Finally, the resulting feature vectors, combined with the original rating matrix and side information, are fed into a semi-autoencoder for recommendation prediction. We ran comprehensive experiments on the MovieLens datasets. The results demonstrate the effectiveness of MFSAE compared to state-of-the-art methods.

Recommender system expedited quantum control optimization

Quantum control optimization algorithms are routinely used to synthesize optimal quantum gates or to realize efficient quantum state transfers. The computational resource required for the optimization is an essential consideration in order to scale toward quantum control of larger registers. Here, we propose and demonstrate the use of a machine learning method, specifically the recommender system (RS), to deal with the challenge of enhancing computational efficiency. Given a sparse database of a set of products and their customer ratings, RS is used to efficiently predict unknown ratings. In the quantum control problem, each iteration of a numerical optimization algorithm typically involves evaluating a large number of parameters, such as gradients or fidelities, which can be tabulated as a rating matrix. We establish that RS can rapidly and accurately predict elements of such a sparse rating matrix. Using this approach, we expedite a gradient ascent based quantum control optimization, namely GRAPE, and demonstrate the faster construction of two-qubit CNOT gate in registers with up to 8 qubits. We also describe and implement the enhancement of the computational speed of a hybrid algorithm involving simulated annealing as well as gradient ascent. Moreover, the faster construction of three-qubit Toffoli gates further confirmed the applicability of RS in larger registers.

Exploiting Dual-Attention Networks for Explainable Recommendation in Heterogeneous Information Networks.

The aim of explainable recommendation is not only to provide recommended items to users, but also to make users aware of why these items are recommended. Traditional recommendation methods infer user preferences for items using user-item rating information. However, the expressive power of latent representations of users and items is relatively limited due to the sparseness of the user-item rating matrix. Heterogeneous information networks (HIN) provide contextual information for improving recommendation performance and interpreting the interactions between users and items. However, due to the heterogeneity and complexity of context information in HIN, it is still a challenge to integrate this contextual information into explainable recommendation systems effectively. In this paper, we propose a novel framework-the dual-attention networks for explainable recommendation (DANER) in HINs. We first used multiple meta-paths to capture high-order semantic relations between users and items in HIN for generating similarity matrices, and then utilized matrix decomposition on similarity matrices to obtain low-dimensional sparse representations of users and items. Secondly, we introduced two-level attention networks, namely a local attention network and a global attention network, to integrate the representations of users and items from different meta-paths for obtaining high-quality representations. Finally, we use a standard multi-layer perceptron to model the interactions between users and items, which predict users' ratings of items. Furthermore, the dual-attention mechanism also contributes to identifying critical meta-paths to generate relevant explanations for users. Comprehensive experiments on two real-world datasets demonstrate the effectiveness of DANER on recommendation performance as compared with the state-of-the-art methods. A case study illustrates the interpretability of DANER.

Exemplar-based large-scale low-rank matrix decomposition for collaborative prediction

Recommender system is one of the most effective tools to solve the problem of information overload. As a popular method for recommendation system, regularized singular value decomposition (RSVD) has the advantage of prediction accuracy. However, with the growing of the size of rating matrix A, RSVD suffers from both ‘out of memory’ and high computational cost. To alleviate these disadvantages, we utilize CUR decomposition approach to reduce the memory consumption before RSVD is applied. Additionally, the rating matrix A often is sparse, so we propose a novel column sampling algorithm and sparseness measure to solve the data sparse problem. The main computation cost in the original RSVD is to compute and respectively. While replacing N by CUR or C in RSVD, we can reduce the computational cost from to (where c is the size of data subspace, m and n are the size of the input matrix, t is the number of iterations, is the number of features). Because CUR is explicitly expressed in terms of a small number of actual columns and actual rows of the original data matrix, the result of matrix decomposition has better interpretability. The advantage of what we devised CUR+RSVD and C+RSVD collaborative prediction approaches is that, they not only can deal with the large scale matrix rapidly but also preserve the sparsity of the original matrix, more interestingly, our approaches have higher prediction accuracy. Experimental results on Movielens, Joke data set, etc. show that what we proposed methods can handle the sparsity issue on large-scale low-rank matrix effectively. Compared with RSVD, it can achieve far better prediction accuracy and recommendation result, meanwhile save about 70% training time at the same dataset.

Modeling and Applying Implicit Dormant Features for Recommendation via Clustering and Deep Factorization.

E-commerce systems experience poor quality of performance when the number of records in the customer database increases due to the gradual growth of customers and products. Applying implicit hidden features into the recommender system (RS) plays an important role in enhancing its performance due to the original dataset's sparseness. In particular, we can comprehend the relationship between products and customers by analyzing the hierarchically expressed hidden implicit features of them. Furthermore, the effectiveness of rating prediction and system customization increases when the customer-added tag information is combined with hierarchically structured hidden implicit features. For these reasons, we concentrate on early grouping of comparable customers using the clustering technique as a first step, and then, we further enhance the efficacy of recommendations by obtaining implicit hidden features and combining them via customer's tag information, which regularizes the deep-factorization procedure. The idea behind the proposed method was to cluster customers early via a customer rating matrix and deeply factorize a basic WNMF (weighted nonnegative matrix factorization) model to generate customers preference's hierarchically structured hidden implicit features and product characteristics in each cluster, which reveals a deep relationship between them and regularizes the prediction procedure via an auxiliary parameter (tag information). The testimonies and empirical findings supported the viability of the proposed approach. Especially, MAE of the rating prediction was 0.8011 with 60% training dataset size, while the error rate was equal to 0.7965 with 80% training dataset size. Moreover, MAE rates were 0.8781 and 0.9046 in new 50 and 100 customer cold-start scenarios, respectively. The proposed model outperformed other baseline models that independently employed the major properties of customers, products, or tags in the prediction process.

Wingman: A New Movie Recommendation System Algorithm

In this rising new era, the world is growing faster and so are we. People nowadays need effortless services, and recommendation system is one of them. They are present and used everywhere, whether it's advertising, e-commerce or any other domain. Companies such as Netflix, YouTube, Amazon, Spotify rely on recommendation systems to boost their sales. Moreover, it increases the engagement of users with a particular app or website as it tends to show more relevant individualized content. It basically takes the user’s past history as an input and then using filtering techniques it predicts the most suitable item/content for the user as an output. The main objective of this paper is to predict movies most desired by the user with as much accuracy as possible. In this paper, I will provide a brief description of various filtering methods and the particular techniques that I used to achieve the desired result. I have used Tf-Idf to quantify the overview of the movies, then did a pairwise similarity for the Content Based Filtering. This allows the user to watch movies based on their watch history according to the plot of the movies. For Collaborative Filtering, I have used Matrix Factorization to generate real-time recommendations based on user-movie rating matrix. Correlation Coefficient is used to calculate the score. The higher the score, the more likely the movie is liked by the user. I have used the voting system for Hybrid Filtering. Weighted Rating Score is calculated with the help of the votes given to the movies by the users. Then a popularity feature is also used to generate more meaningful movie recommendations. MinMax Scalar is used to normalize the data, and then fifty percent priority is given to both Weighted Rating Score and popularity and a final score is calculated. Using this final score, popular or top movies are generated. The databases used are retrieved from MovieLens and Kaggle. Consequently, my proposed system will generate recommendations based on the plot of the movie using tf-idf and cosine similarity, based on user-movie rating matrix and correlation coefficient, based on voting and popularity basis.

Collaborative Filtering system based on multi-level user clustering and aspect sentiment

A Collaborative Filtering (CF) method predicts an unknown overall rating of a target user towards an item based on the known overall ratings of the users that are similar to the target user. The similarity between two users is generally found based on their overall ratings toward items that both have reviewed. Two users may have similar overall ratings towards a given item, but different sentiments towards various aspects of the item. Understanding the effect of user sentiment towards specific aspects on overall ratings will sharpen estimates of user similarity as well as provide an rationale for making specific recommendations. We propose an Aspect-Sentiments based Multi-level Clustering of Users (ASMCU) approach that finds the multiple clusters of users similar to a specific user where similarity between users is based on various aspect sentiments. The proposed ASMCU CF approach can be used to predict both the overall ratings and the aspect-sentiments. The ASMCU based CF approach performed mostly better than and sometimes comparable to the eight well-established CF methods that rely only on the overall ratings or a particular aspect-sentiments. Note however that the ASMCU can also explicitly justify the recommendation in terms of aspect sentiments. We evaluated our approach using three datasets: One Hotel dataset and Two Beer datasets. The Hotel dataset involved six aspects and each Beer dataset has four aspects. Each dataset has one overall rating matrix and one sentiment tensor.

Adaptive preference transfer for personalized IoT entity recommendation

• An IoT entity recommendation method based on adaptive preference transfer is proposed. • A lightweight user feedback feature embedding method is proposed to solve the problem of sparse user feedback. • The rigorous experiments are designed to verify the validity of the proposed method. Internet of Things (IoT) recommendation can effectively improve the convenience and intelligence of users in obtaining information about interested physical entities in a huge entity search space. However, existing transfer learning-based recommendation methods mainly focus on Internet resources and services, lack personalized transfer weight consideration for different user preferences, and fail to address the entity rating matrix sparsity problem, resulting in limited IoT entity recommendation performance. Thus, we design an adaptive preference transfer IoT entity (APTE) recommendation method in this paper. Firstly, considering various user preference characteristics, an adaptive dual-domain transfer model for item domain and social domain is designed to meet users’ personalized requirements. Then, a lightweight user feedback embedding method is proposed to mine the explicit and implicit features and to embed the entity rating matrix to solve the problem of sparse user feedback information. Simulation results demonstrate that APTE can effectively improve the recommendation performance compared with state-of-the-art baselines.

An Improved Web Service Recommendation Method based on Decomposition Machine Model

With the increasing number of Web services with similar functions on the Internet, traditional collaborative filtering service recommendation methods may encounter problems such as data sparseness, cold start, and poor scalability. To solve the above problems, this project proposes a new Web service recommendation method based on the decomposition machine model. The method decomposes the user trust relationship matrix and the product rating matrix while adding the geographic location information of the service, and transforms the correlation matrix of the calculated user feature vector and item feature vector into the same latent factor space by means of a decomposition machine. Optimize training model parameters to provide users with accurate prediction scores. The ultimate purpose of QoS prediction is to recommend high-quality services to users, improve the efficiency of users' discovery and selection of high-quality services, and ultimately promote the utilization of network Web services and promote service providers to release higher-quality services. Scientific significance, but also has better application value.