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A High Utility Itemset (HUI) mining is an important problem in the data mining literature that considers utilities of items (such as profits and margins) to discover interesting patterns from transactional databases. Several data structures, pruning strategies and algorithms have been proposed in the literature to efficiently mine high utility itemsets. Most of these works, however, do not consider itemsets with negative unit profits that provide greater flexibility to a decision maker to determine profitable itemsets. This paper aims to advance the state-of-the-art and presents a generalized high utility mining (GHUM) method that considers both positive and negative unit profits. The proposed method uses a simplified utility-list data structure for storing itemset information during the mining process. The paper also introduces a novel utility based anti-monotonic property to improve the performance of HUI mining. Furthermore, GHUM adapts key pruning strategies from the basic HUI mining literature and presents new pruning strategies to significantly improve the performance of mining. The proposed method is evaluated on a set of benchmark sparse and dense datasets and compared against a state-of-the-art method. Rigorous experimental evaluation is performed and implications of the key findings are also presented. In general, GHUM was found to deliver more than an order of magnitude improvement at a fraction of the memory over the state-of-the-art FHN method. [ABSTRACT FROM AUTHOR]

By now, 13 cross-border e-commerce comprehensive pilot areas have been approved by the State Council of China; Dalian and Tianjin are two of them. But with the development of the construction of the cross-border e-commerce comprehensive pilot areas, the competition between those pilot areas is inevitable. Dalian and Tianjin are located in the Bohai Sea and the distance between them is only 800 kilometers. For Dalian and Tianjin they are in thus competitive situations: first they have to compete with each other; second since they are located in Bohai Sea (North China), they have to compete with other cross-border e-commerce comprehensive pilot areas (South China). In this paper, our aim is to build models to provide best price strategies for these two cities. Based on the two-sided market theory and the geographical position, this paper builds two competitive theory models. Through the analyzing of the equilibrium, we get two main results: (1) according to different service area, the cities (Dalian and Tianjin) should have different price; (2) the two-sided market characters have an impact on their strategies. [ABSTRACT FROM AUTHOR]

Sales fluctuations lead to variations in the output levels affecting technical efficiency measures of operations when units sold are used at an output measure. The present study uses the concept of 'effective production' and 'effectiveness' to account for the effect of sales on operational performance measurements in a production system. The effectiveness measure complements the efficiency measure which does not account for the sales effect. The Malmquist productivity index is used to measure the sales effects characterized as the difference between the production function associated with efficiency and the sales-truncated production function associated with effectiveness. The proposed profit effectiveness is distinct from profit efficiency in that it accounts for sales. An empirical study of US airlines demonstrates the proposed method which describes the strategic position of a firm and a productivity-change analysis. These results demonstrate the concept of effectiveness and quantifies the effect of using sales as output. [ABSTRACT FROM AUTHOR]

We study the problem of bandwidth allocation with multiple interferences . In this problem the input consists of a set of users and a set of base stations. Each user has a list of requests, each consisting of a base station, a frequency demand, and a profit that may be gained by scheduling this request. The goal is to find a maximum profit set of user requests S that satisfies the following conditions: (i) S contains at most one request per user, (ii) the frequency sets allotted to requests in S that correspond to the same base station are pairwise non-intersecting, and (iii) the QoS received by any user at any frequency is reasonable according to an interference model . In this paper we consider two variants of bandwidth allocation with multiple interferences. In the first each request specifies a demand that can be satisfied by any subset of frequencies that is large enough. In the second each request specifies a specific frequency interval. Furthermore, we consider two interference models, multiplicative and additive . We show that these problems are extremely hard to approximate if the interferences depend on both the interfered and the interfering base stations. On the other hand, we provide constant factor approximation algorithms for both variants of bandwidth allocation with multiple interferences for the case where the interferences depend only on the interfering base stations. We also consider a restrictive special case that is closely related to the Knapsack problem. We show that this special case is NP-hard and that it admits an FPTAS. [ABSTRACT FROM AUTHOR]

I examine the relationship between vertical separation and gasoline stations' prices and sales. The endogeneity of stations' organizational forms is addressed using both panel methods and an instrumental variables strategy. Controlling for the endogeneity of form, I find that vertical separation raises margins by 25%-45% but does not have a statistically significant impact on output. I interpret these results as suggesting that vertical separation induces local agents to exert effort in ways that increase consumers' demand. ( JEL L14, L24, L81) [ABSTRACT FROM AUTHOR]

This work considers the make-to-order production of multiple-line production considering the production rate, production time interval, production yield, holding cost, manufacturing cost, set-up cost, the penalty cost of shortage, and constrained delivery deadline. Based on the research motivation of efficient and fast decisions, this paper constructs a mathematical model for achieving the maximum total profit, and selects the particle swarm optimisation (PSO) as the approach to a solution due to its simplicity and rapid convergence. The proposed model can be categorised as a nonlinear programming (NLP) model, and can also function as a decision-making tool for real-time analyses of multiple-line production planning. A numerical example is then followed to describe and analyse the results. Actually, this study is a computerised tool to deal with the production planning of make-to-order production by constrained delivery deadlines. This research can provide not only an efficient but also a fast referenced decision for an enterprise to face fast-changing business environments, and it can solve other cases easily by changing only its input parameters. [ABSTRACT FROM AUTHOR]

With more and more B2C companies start to provide free delivery service to attract the customers, how to design the free-shipping rule to maximize the retailers' profit and market share has become a new problem facing the online retailers. This paper decomposed the problem into a two-stage model: customer's behavior model and retailer's profit model. First, it built the customer's behavior model to get the optimal purchasing decisions of consumers under a given free shipping threshold and product price. And then it maximized the retailer's profit model which was established on the result of the customer's behavior function to determine the optimal free shipping policy of retailer. Through algorithm design and numerical study, it found that the retailer's profits would jump when free shipping threshold was set at the boundary of product price combination value. [ABSTRACT FROM AUTHOR]

This paper presents the application of the concept of moving sidewalks at railway stations (the movable platform) including the calculation of electricity consumption. Particular focus was placed on issue of energy profit and loss in two stages - through the loss (consumption) of energy by using a moving sidewalk at a railway station platform and the profit (reduced consumption) of energy, by the lack of having to start the train, that supports movable platform, from the initial speed of 0 km/h. [ABSTRACT FROM AUTHOR]

The article discusses two papers on education published in this issue including one by Ferdinand Verhulst on profits and one by James Bisgard on the Mountain Pass Lemma of Ambrosetti and Rabinowitz.