Efficient Utilization of Dependency Pattern and Sequential Covering for Aspect Extraction Rule Learning

The use of dependency rules for aspect extraction tasks in aspect-based sentiment analysis is a promising approach. One problem with this approach is incomplete rules. This paper presents an aspect extraction rule learning method that combines dependency rules with the Sequential Covering algorithm. Sequential Covering is known for its characteristics in constructing rules that increase positive examples covered and decrease negative ones. This property is vital to make sure that the rule set used has high performance, but not inevitably high coverage, which is a characteristic of the aspect extraction task. To test the new method, four datasets were used from four product domains and three baselines: Double Propagation, Aspectator, and a previous work by the authors. The results show that the proposed approach performed better than the three baseline methods for the F-measure metric, with the highest F-measure value at 0.633

Pedestrian Attribute Recognition: A Survey

Recognizing pedestrian attributes is an important task in computer vision community due to it plays an important role in video surveillance. Many algorithms has been proposed to handle this task. The goal of this paper is to review existing works using traditional methods or based on deep learning networks. Firstly, we introduce the background of pedestrian attributes recognition (PAR, for short), including the fundamental concepts of pedestrian attributes and corresponding challenges. Secondly, we introduce existing benchmarks, including popular datasets and evaluation criterion. Thirdly, we analyse the concept of multi-task learning and multi-label learning, and also explain the relations between these two learning algorithms and pedestrian attribute recognition. We also review some popular network architectures which have widely applied in the deep learning community. Fourthly, we analyse popular solutions for this task, such as attributes group, part-based, \emph{etc}. Fifthly, we shown some applications which takes pedestrian attributes into consideration and achieve better performance. Finally, we summarized this paper and give several possible research directions for pedestrian attributes recognition. The project page of this paper can be found from the following website: \url{https://sites.google.com/view/ahu-pedestrianattributes/}.Comment: Check our project page for High Resolution version of this survey: https://sites.google.com/view/ahu-pedestrianattributes

Poverty and Inequality Impacts of Trade Policy Reforms in South Africa

South Africa has undergone significant trade liberalization since the end of apartheid. Average protection has fallen while openness has increased. However, economic growth has been insufficient to make inroads into the high unemployment levels. Poverty levels have also risen. The country's experience presents an interesting challenge for many economists that argue that trade liberalization is pro-poor and pro-growth. This study investigates the short and long term effects of trade liberalization using a dynamic microsimulation computable general equilibrium approach. Trade liberalization has been simulated by a complete removal of all tariffs on imported goods and services, and by a combination of tariff removal and an increase of total factor productivity. The main findings are that a complete tariff removal on imports has negative welfare and poverty reduction impacts in the short run which turns positive in the long term due to the accumulation effects. When the tariff removal simulation is combined with an increase of total factor productivity, the short and long run effects are both positive in terms of welfare and poverty reduction. The mining sector (highest export orientation) is the biggest winner from the reforms while the textiles sector (highest initial tariff rate) is the biggest loser. African and Colored households gain the most in terms of welfare and numbers being pulled out of absolute poverty by trade liberalization.Sequential dynamic CGE, microsimulation, trade liberalization, total factor productivity, poverty, welfare, growth, South Africa

South Africa Trade Liberalization and Poverty in a Dynamic Microsimulation CGE Model

South Africa has undergone significant trade liberalization since the end of apartheid. Average protection has fallen while openness has increased. However, economic growth has been insufficient to make inroads into the high unemployment levels. Poverty levels have also risen. The country’s experience presents an interesting challenge for many economists that argue that trade liberalization is pro-poor and pro-growth. This study investigates the short and long term effects of trade liberalization using a dynamic microsimulation computable general equilibrium approach. Trade liberalization has been simulated by a complete removal of all tariffs on imported goods and services, and by a combination of tariff removal and an increase of total factor productivity. The main findings are that a complete tariff removal on imports has negative welfare and poverty reduction impacts in the short run which turns positive in the long term due to the accumulation effects. When the tariff removal simulation is combined with an increase of total factor productivity, the short and long run effects are both positive in terms of welfare and poverty reduction. The mining sector (highest export orientation) is the biggest winner from the reforms while the textiles sector (highest initial tariff rate) is the biggest loser. African and Colored households gain the most in terms of welfare and numbers being pulled out of absolute poverty by trade liberalization.Sequential dynamic CGE, microsimulation, trade liberalization, total factor productivity, poverty, welfare, growth, South Africa

Modeling Adoption and Usage of Competing Products

The emergence and wide-spread use of online social networks has led to a dramatic increase on the availability of social activity data. Importantly, this data can be exploited to investigate, at a microscopic level, some of the problems that have captured the attention of economists, marketers and sociologists for decades, such as, e.g., product adoption, usage and competition. In this paper, we propose a continuous-time probabilistic model, based on temporal point processes, for the adoption and frequency of use of competing products, where the frequency of use of one product can be modulated by those of others. This model allows us to efficiently simulate the adoption and recurrent usages of competing products, and generate traces in which we can easily recognize the effect of social influence, recency and competition. We then develop an inference method to efficiently fit the model parameters by solving a convex program. The problem decouples into a collection of smaller subproblems, thus scaling easily to networks with hundred of thousands of nodes. We validate our model over synthetic and real diffusion data gathered from Twitter, and show that the proposed model does not only provides a good fit to the data and more accurate predictions than alternatives but also provides interpretable model parameters, which allow us to gain insights into some of the factors driving product adoption and frequency of use

MCRapper: Monte-Carlo Rademacher Averages for Poset Families and Approximate Pattern Mining

We present MCRapper, an algorithm for efficient computation of Monte-Carlo Empirical Rademacher Averages (MCERA) for families of functions exhibiting poset (e.g., lattice) structure, such as those that arise in many pattern mining tasks. The MCERA allows us to compute upper bounds to the maximum deviation of sample means from their expectations, thus it can be used to find both statistically-significant functions (i.e., patterns) when the available data is seen as a sample from an unknown distribution, and approximations of collections of high-expectation functions (e.g., frequent patterns) when the available data is a small sample from a large dataset. This feature is a strong improvement over previously proposed solutions that could only achieve one of the two. MCRapper uses upper bounds to the discrepancy of the functions to efficiently explore and prune the search space, a technique borrowed from pattern mining itself. To show the practical use of MCRapper, we employ it to develop an algorithm TFP-R for the task of True Frequent Pattern (TFP) mining. TFP-R gives guarantees on the probability of including any false positives (precision) and exhibits higher statistical power (recall) than existing methods offering the same guarantees. We evaluate MCRapper and TFP-R and show that they outperform the state-of-the-art for their respective tasks

Feature Extraction and Duplicate Detection for Text Mining: A Survey

Text mining, also known as Intelligent Text Analysis is an important research area. It is very difficult to focus on the most appropriate information due to the high dimensionality of data. Feature Extraction is one of the important techniques in data reduction to discover the most important features. Proce- ssing massive amount of data stored in a unstructured form is a challenging task. Several pre-processing methods and algo- rithms are needed to extract useful features from huge amount of data. The survey covers different text summarization, classi- fication, clustering methods to discover useful features and also discovering query facets which are multiple groups of words or phrases that explain and summarize the content covered by a query thereby reducing time taken by the user. Dealing with collection of text documents, it is also very important to filter out duplicate data. Once duplicates are deleted, it is recommended to replace the removed duplicates. Hence we also review the literature on duplicate detection and data fusion (remove and replace duplicates).The survey provides existing text mining techniques to extract relevant features, detect duplicates and to replace the duplicate data to get fine grained knowledge to the user