The Experts below are selected from a list of 3366 Experts worldwide ranked by ideXlab platform

Srikumar Krishnamoorthy - One of the best experts on this subject based on the ideXlab platform.

  • Efficient mining of high utility itemsets with multiple minimum utility thresholds
    Engineering Applications of Artificial Intelligence, 2018
    Co-Authors: Srikumar Krishnamoorthy
    Abstract:

    Abstract 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.

  • Efficiently mining high utility itemsets with negative unit Profits
    Knowledge-Based Systems, 2018
    Co-Authors: Srikumar Krishnamoorthy
    Abstract:

    Abstract 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.

Christopher Chibwana - One of the best experts on this subject based on the ideXlab platform.

  • Profits and Margins along Uganda's charcoal value
    2010
    Co-Authors: Gerald Shively, Pamela Jagger, Dick Sserunkuuma, A. Arinaitwe, Christopher Chibwana
    Abstract:

    SUMMARY This paper characterizes the charcoal value chain in Uganda, focusing on production and trade in three districts in the west central region of the country. Data come from surveys of 407 charcoal value chain participants undertaken in 2008. The surveys included 171 charcoalproducing households and 236 non-producer participants including agents, traders, transporters and retailers. Linear regression models are used to study overall Profits and per-unit marketing Margins along the value chain and to test several hypotheses regarding the importance of location, human and social capital, and asset ownership on observed economic returns and scale of activity. Evidence suggests the greatest overall returns to participation in the charcoal value chain are found among traders. Returns are positively correlated with the scale of activity. Controlling for a participant’s role in the charcoal trade, his or her characteristics, and available assets, we find little or no evidence of differences in economic returns among districts, despite widespread popular views of differences in available supply of charcoal. Location of production relative to major markets, and location-specific levels of monitoring and enforcement are not strongly correlated with observed outcomes.

  • Profits and Margins along Uganda's Charcoal Value Chain
    International Forestry Review, 2010
    Co-Authors: Gerald Shively, Pamela Jagger, Dick Sserunkuuma, A. Arinaitwe, Christopher Chibwana
    Abstract:

    This paper characterizes the charcoal value chain in Uganda, focusing on production and trade in three districts in the west central region of the country. Data come from surveys of 407 charcoal value chain participants undertaken in 2008. The surveys included 171 charcoal-producing households and 236 non-producer participants including agents, traders, transporters and retailers. Linear regression models are used to study overall Profits and per-unit marketing Margins along the value chain and to test several hypotheses regarding the importance of location, human and social capital, and asset ownership on observed economic returns and scale of activity. Evidence suggests the greatest overall returns to participation in the charcoal value chain are found among traders. Returns are positively correlated with the scale of activity. Controlling for a participant's role in the charcoal trade, his or her characteristics, and available assets, we find little or no evidence of differences in economic returns among districts, despite widespread popular views of differences in available supply of charcoal. Location of production relative to major markets, and location-specific levels of monitoring and enforcement are not strongly correlated with observed outcomes.

Gerald Shively - One of the best experts on this subject based on the ideXlab platform.

  • Profits and Margins along Uganda's charcoal value
    2010
    Co-Authors: Gerald Shively, Pamela Jagger, Dick Sserunkuuma, A. Arinaitwe, Christopher Chibwana
    Abstract:

    SUMMARY This paper characterizes the charcoal value chain in Uganda, focusing on production and trade in three districts in the west central region of the country. Data come from surveys of 407 charcoal value chain participants undertaken in 2008. The surveys included 171 charcoalproducing households and 236 non-producer participants including agents, traders, transporters and retailers. Linear regression models are used to study overall Profits and per-unit marketing Margins along the value chain and to test several hypotheses regarding the importance of location, human and social capital, and asset ownership on observed economic returns and scale of activity. Evidence suggests the greatest overall returns to participation in the charcoal value chain are found among traders. Returns are positively correlated with the scale of activity. Controlling for a participant’s role in the charcoal trade, his or her characteristics, and available assets, we find little or no evidence of differences in economic returns among districts, despite widespread popular views of differences in available supply of charcoal. Location of production relative to major markets, and location-specific levels of monitoring and enforcement are not strongly correlated with observed outcomes.

  • Profits and Margins along Uganda's Charcoal Value Chain
    International Forestry Review, 2010
    Co-Authors: Gerald Shively, Pamela Jagger, Dick Sserunkuuma, A. Arinaitwe, Christopher Chibwana
    Abstract:

    This paper characterizes the charcoal value chain in Uganda, focusing on production and trade in three districts in the west central region of the country. Data come from surveys of 407 charcoal value chain participants undertaken in 2008. The surveys included 171 charcoal-producing households and 236 non-producer participants including agents, traders, transporters and retailers. Linear regression models are used to study overall Profits and per-unit marketing Margins along the value chain and to test several hypotheses regarding the importance of location, human and social capital, and asset ownership on observed economic returns and scale of activity. Evidence suggests the greatest overall returns to participation in the charcoal value chain are found among traders. Returns are positively correlated with the scale of activity. Controlling for a participant's role in the charcoal trade, his or her characteristics, and available assets, we find little or no evidence of differences in economic returns among districts, despite widespread popular views of differences in available supply of charcoal. Location of production relative to major markets, and location-specific levels of monitoring and enforcement are not strongly correlated with observed outcomes.

Ru Xie - One of the best experts on this subject based on the ideXlab platform.

  • Bank Profits and Margins in a World of Negative Rates
    2019
    Co-Authors: Philip Molyneux, Alessio Reghezza, Ru Xie
    Abstract:

    This paper investigates the influence of negative interest rate policy (NIRP) on bank Margins and profitability. Using a dataset comprising 7242 banks from 33 OECD member countries over 2012-2016 and a difference-in-differences methodology, we find that bank Margins and Profits fell in NIRP-adopter countries compared to countries that did not adopt the policy. The results are robust to a variety of checks. This adverse NIRP effect appears to have been stronger for banks that were small, operating in competitive system as well as in countries where floating loan rates predominate.

Dick Sserunkuuma - One of the best experts on this subject based on the ideXlab platform.

  • Profits and Margins along Uganda's charcoal value
    2010
    Co-Authors: Gerald Shively, Pamela Jagger, Dick Sserunkuuma, A. Arinaitwe, Christopher Chibwana
    Abstract:

    SUMMARY This paper characterizes the charcoal value chain in Uganda, focusing on production and trade in three districts in the west central region of the country. Data come from surveys of 407 charcoal value chain participants undertaken in 2008. The surveys included 171 charcoalproducing households and 236 non-producer participants including agents, traders, transporters and retailers. Linear regression models are used to study overall Profits and per-unit marketing Margins along the value chain and to test several hypotheses regarding the importance of location, human and social capital, and asset ownership on observed economic returns and scale of activity. Evidence suggests the greatest overall returns to participation in the charcoal value chain are found among traders. Returns are positively correlated with the scale of activity. Controlling for a participant’s role in the charcoal trade, his or her characteristics, and available assets, we find little or no evidence of differences in economic returns among districts, despite widespread popular views of differences in available supply of charcoal. Location of production relative to major markets, and location-specific levels of monitoring and enforcement are not strongly correlated with observed outcomes.

  • Profits and Margins along Uganda's Charcoal Value Chain
    International Forestry Review, 2010
    Co-Authors: Gerald Shively, Pamela Jagger, Dick Sserunkuuma, A. Arinaitwe, Christopher Chibwana
    Abstract:

    This paper characterizes the charcoal value chain in Uganda, focusing on production and trade in three districts in the west central region of the country. Data come from surveys of 407 charcoal value chain participants undertaken in 2008. The surveys included 171 charcoal-producing households and 236 non-producer participants including agents, traders, transporters and retailers. Linear regression models are used to study overall Profits and per-unit marketing Margins along the value chain and to test several hypotheses regarding the importance of location, human and social capital, and asset ownership on observed economic returns and scale of activity. Evidence suggests the greatest overall returns to participation in the charcoal value chain are found among traders. Returns are positively correlated with the scale of activity. Controlling for a participant's role in the charcoal trade, his or her characteristics, and available assets, we find little or no evidence of differences in economic returns among districts, despite widespread popular views of differences in available supply of charcoal. Location of production relative to major markets, and location-specific levels of monitoring and enforcement are not strongly correlated with observed outcomes.