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Journal Articles | 2018

Efficient mining of high utility itemsets with multiple minimum utility thresholds

Srikumar Krishnamoorthy

Engineering Applications of Artificial Intelligence

Mining high utility itemsets is considered to be one of the important and challenging problems in the data mining literature. The problem offers greater flexibility to a decision maker in using item utilities such as profits and margins to mine interesting and actionable patterns from databases. Most of the current works in the literature, however, apply a single minimum utility threshold value and fail to consider disparities in item characteristics. This paper proposes an efficient method (MHUI) to mine high utility itemsets with multiple minimum utility threshold values. The presented method generates high utility itemsets in a single phase without an expensive intermediate candidate generation process. It introduces the concept of suffix minimum utility and presents generalized pruning strategies for efficiently mining high utility itemsets. The performance of the algorithm is evaluated against the state-of-the-art methods (HUI-MMU-TE and HIMU-EUCP) on eight benchmark datasets. The experimental results show that the proposed method delivers two to three orders of magnitude execution time improvement over the HUI-MMU-TE method. In addition, MHUI delivers one to two orders of magnitude execution time improvement over the HIMU-EUCP method, especially on moderately long and dense benchmark datasets. The memory requirements of the proposed algorithm was also found to be significantly lower.

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Journal Articles | 2018

Does telecommuting promote sustainable travel and physical activity?

Sandip Chakrabarti

Journal of Transport and Health

Researchers have explored the efficacy of telecommuting as a travel demand management strategy in the U.S. Conditions under which telecommuting can reduce VMT (vehicle miles traveled) and ease peak-period traffic congestion have been extensively investigated; empirical findings are well documented in the literature. Analysis of the impact of telecommuting on non-motorized travel, public transit use, and physical activity, however, has received relatively less attention in the past.

In this paper, I use the 2009 U.S. National Household Travel Survey to explore how telecommuting is associated with usual travel behavior, i.e. walking/bicycling, transit use and driving, as well as with average time spent in daily physical activity. I also compare telecommuters’ travel behavior and physical activity on a typical workday in telecommuting vs. non-telecommuting scenarios.

I find that frequent telecommuting (4+ times/month) is associated with 15% more walk trips per week, 56% higher odds of 1+ transit trip per month, 44% higher odds of 30+ minutes of physical activity per day, and 27% higher odds of driving 20,000+ miles per year compared to no-telecommuting scenario. On a typical workday, telecommuting is associated with 41% higher odds of walking/bicycling > 1 mile, 71% higher odds of 30+ minutes of physical activity, 71% lower odds of riding transit, and 3.58 times greater odds of driving < 10 miles. Findings suggest that telecommuting can increase non-motorized travel and physical activity in the presence of latent demand for active living. Increase in transit ridership and reduction in VMT are not automatic. Planning and policy implications are discussed.

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Journal Articles | 2018

Mining top-k high utility itemsets with effective threshold raising strategies

Srikumar Krishnamoorthy

Expert Systems With Applications

Top-K High Utility Itemset (HUI) mining problem offers greater flexibility to a decision maker in specifying her/his notion of item utility and the desired number of patterns. It obviates the need for a decision maker to determine an appropriate minimum utility threshold value using a trial-and-error process. The top-k HUI mining problem, however, is more challenging and requires use of effective threshold raising strategies. Several threshold raising strategies have been proposed in the literature to improve the overall efficiency of mining top-k HUIs. This paper advances the state-of-the-art and presents a new Top-K HUI method (THUI). A novel Leaf Itemset Utility (LIU) structure and a threshold raising strategy is proposed to significantly improve the efficiency of mining top-k HUIs. A new utility lower bound estimation method is also introduced to quickly raise the minimum utility threshold value. The proposed THUI method is experimentally evaluated on several benchmark datasets and compared against two state-of-the-art methods. Our experimental results reveal that the proposed THUI method offers one to three orders of magnitude runtime performance improvement over other related methods in the literature, especially on large, dense and long average transaction length datasets. In addition, the memory requirements of the proposed method are found to be lower.

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Journal Articles | 2018

Food value chain investments and the small farmer linkage: Indian experience, potential, and policy

Sukhpal Singh

World Food Policy

The agri-food value chains in the developing world are evolving fast due to many changes in policy and practice. In India, modern domestic food supermarkets have been present for more than 15 years now. Furthermore, in late 2012, foreign direct investment in multi-brand retail trade, including food, was permitted up to 51% of equity with other conditions of investment and operations. This paper tries to understand the role of investment (both domestic and foreign) in food/fibre value chains in improving the farmer/producer linkage. It uses empirical evidence from the experience of Indian domestic food retail supermarkets, and (mostly) foreign investment-based wholesale supermarkets in India, to examine the role such investments can play. It specifically examines the role and implications of investments in supermarkets for farmer income improvement, from a value chain perspective. It also explores various mechanisms which could be used to leverage the presence of such investments in food supermarkets and analyses the role of policy and regulation to promote/protect the small producer interests in food markets.

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Journal Articles | 2018

Promoting and managing FPOs in India for efficiency, effectiveness and sustainability: Challenges, policies and best practices

Sukhpal Singh

Cooperative Perspective, Spl Issue(September)

Journal Articles | 2018

Nocebo effects from negative product information: when information hurts, paying money could heal

Sukhpal Singh and Arvind Sahay

Journal of Consumer marketing

Purpose

This research aimed to find whether information about a product can give rise to negative perceptions even in inert situations (nocebo effects), and to understand how price levels impact such judgments.

Design/methodology/approach

In all experiments, participants were exposed to negative product information in the form of potential side-effects. In an initial study, a higher non-discounted versus a discounted price frame was presented for a health drink after customers were exposed to negative aspects. Then, in experiment 1, price (high vs low) and exposure to information (no information vs negative information) was manipulated for skin creams where participants physically evaluated the cream. In experiment 2, price was manipulated at three levels (low, high, discounted) orthogonally with product information (no negative information vs with negative information) to get a more nuanced understanding.

Findings

In the initial study, after exposure to negative information, the non-discounted group had more positive ratings for the drink. Study 1 showed that reading about negative information resulted in a nocebo effect on perception of dryness (side-effect). Moreover, when no information was presented, perception of dryness by low and high price groups were similar but in the face of negative information, perception of dryness by low-price group was more pronounced compared to a high-price group. Study 2 conceptually replicated the effect and also confirmed that not only discounts (commonly linked with product quality), but absolute price levels also show a similar effect.

Practical implications

Nocebo effects have been rarely documented in consumer research. This research showed how simply reading generically about potential side effects gives rise to nocebo effects. In addition, even though marketers might find it tempting to lower prices when there is negative information about certain product categories, such an action could backfire.

Originality/value

To the best of our knowledge, the link between observable nocebo effects and its link with pricing actions is a novel research thread. We were able to show a nocebo effect on product perception after reading about negative information and also find that a higher price can mitigate the nocebo effect to some extent.

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Journal Articles | 2018

Digital social media: Enabling performance quality of Indian Railways

Sundaravalli Narayanaswami

Journal of Public Affairs

Indian Railways (IR) is the single largest organization that manages and operates a mammoth of transportation services in the World's largest democracy. IR services are operated through 7,137 stations, a route length of 66,030 km, and a total track of 117,996 km. The number of passengers carried every day is 23 million with passenger earnings of INR 42190 crores. Scale of operations translates to humungous everyday challenges. Quite understandably, customer dissatisfaction is prevalent, in spite of subsidized travel fares and multiple initiatives. In recent times, IR has become very active in the digital social media space to provide real-time and dynamic service improvements. In this talk, we will be discussing the beginning of technology intervention in IR, managerial challenges in exploiting technology advancements, and the current status in managing a large-scale public transport operations. We will also discuss about the insights, deployability in comparative segments, and the way forward.

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Journal Articles | 2018

Water ATMs of Indian Railways: Causing a silent revolution

Sundaravalli Narayanaswami

Vikalpa: The Journal for Decision Makers

The case discusses the red tape in the installation and operationalising of automatic water vending machines (AWVMs or popularly, water ATMs) in the railway stations on behalf of the Indian Railways (IR) from the perspectives of the protagonist Mr Siya Ram. Siya Ram is the group general manager of the ‘Rail Neer’ initiative of the Indian Railway Catering and Tourism Corporation (IRCTC), a Government of India enterprise. Rail Neer is the bottled water brand of IRCTC.

The case deals with the product development and project execution of installing water ATMs in Indian railway stations. The project was conceptualized as early as 2007; nearly 50 water ATMs were installed in several railway stations, but the project was soon declared closed due to numerous operational hurdles. The Ministry of Railways (MoR) revived the project in 2015 and assigned IRCTC to install water ATMs in 7,500 stations. After the due process, IRCTC empanelled a set of qualified vendors to install the water ATMs; but the overall progress of commissioning and operationalizing was far from impressive. There were huge delays and hiccups, which had commercial implications for the vendors. Therefore, vendors were likely to be discouraged and could choose to not engage any further in the project. According to Mr Siya Ram, the fundamental issue was the delay in roll out of water ATMs arising due to lack of coordination between the vendors, station superintends, and IRCTC. How he attempts to resolve the issue is the focus of the case.

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Journal Articles | 2018

Functioning of Boards in PSBs in India

Sunil Kumar Maheshwari and Ramesh Bhat

Indian Journal of Industrial Relations

IIMA