• Title/Summary/Keyword: ranking set

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Human Health Risk based Priority Ranking for Hazardous Air Pollutants (대기중 유해 화학 물질의 인체 위해도 우선순위 선정 연구)

  • Park Hoa-sung;Kim Ye-shin;Lee Dong-soo;Shin Dong-chun
    • Environmental Analysis Health and Toxicology
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    • v.19 no.1
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    • pp.81-91
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    • 2004
  • Although it is suggested that risk -based management plan is needed to manage air pollution effectively, we have no resources enough to evaluate all aspects of substances and set priorities. So we need to develop a logical and easy risk-based priority setting method. However, it if impossible that only one generic system that is consistent with all the use is developed. In this study, we proposed a human health risk based priority-setting method for hazardous air pollutants, and ranked priorities for this method. First of all, after investigating previous chemical ranking and scoring systems, we chose appropriate indicators and logics to goal of this study and made a chemical priority ranking method using these. As results, final scores in priority ranking method were derived for 25 substances, and ethylene oxide, acrylonitrile and vinyl chloride were included in high ranks. In addition, same substances were highly ranked when using default values like when using no default, but the scores of hydrofluoric acid and ryan and compounds were sensitive to default values. This study could be important that priorities were set including toxicity type and quality and local inherent exposure conditions and we can set area-specific management guidelines and survey plans as a screening tool.

Other approaches to bivariate ranked set sampling

  • Al-Saleh, Mohammad Fraiwan;Alshboul, Hadeel Mohammad
    • Communications for Statistical Applications and Methods
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    • v.25 no.3
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    • pp.283-296
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    • 2018
  • Ranked set sampling, as introduced by McIntyre (Australian Journal of Agriculture Research, 3, 385-390, 1952), dealt with the estimation of the mean of one population. To deal with two or more variables, different forms of bivariate and multivariate ranked set sampling were suggested. For a technique to be useful, it should be easy to implement in practice. Bivariate ranked set sampling, as introduced by Al-Saleh and Zheng (Australian & New Zealand Journal of Statistics, 44, 221-232, 2002), is not easy to implement in practice, because it requires the judgment ranking of each of the combination of the order statistics of the two characteristics. This paper investigates two modifications that make the method easier to use. The first modification is based on ranking one variable and noting the rank of the other variable for one cycle, and do the reverse for another cycle. The second approach is based on ranking of one variable and giving the second variable the same rank (Concomitant Order Statistic) for one cycle and do the reverse for the other cycle. The two procedures are investigated for an estimation of the means of some well-known distributions. It is show that the suggested approaches can be used in practice and can be more efficient than using SRS. A real data set is used to illustrate the procedure.

An Estimated Closeness Centrality Ranking Algorithm and Its Performance Analysis in Large-Scale Workflow-supported Social Networks

  • Kim, Jawon;Ahn, Hyun;Park, Minjae;Kim, Sangguen;Kim, Kwanghoon Pio
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.3
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    • pp.1454-1466
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    • 2016
  • This paper implements an estimated ranking algorithm of closeness centrality measures in large-scale workflow-supported social networks. The traditional ranking algorithms for large-scale networks have suffered from the time complexity problem. The larger the network size is, the bigger dramatically the computation time becomes. To solve the problem on calculating ranks of closeness centrality measures in a large-scale workflow-supported social network, this paper takes an estimation-driven ranking approach, in which the ranking algorithm calculates the estimated closeness centrality measures by applying the approximation method, and then pick out a candidate set of top k actors based on their ranks of the estimated closeness centrality measures. Ultimately, the exact ranking result of the candidate set is obtained by the pure closeness centrality algorithm [1] computing the exact closeness centrality measures. The ranking algorithm of the estimation-driven ranking approach especially developed for workflow-supported social networks is named as RankCCWSSN (Rank Closeness Centrality Workflow-supported Social Network) algorithm. Based upon the algorithm, we conduct the performance evaluations, and compare the outcomes with the results from the pure algorithm. Additionally we extend the algorithm so as to be applied into weighted workflow-supported social networks that are represented by weighted matrices. After all, we confirmed that the time efficiency of the estimation-driven approach with our ranking algorithm is much higher (about 50% improvement) than the traditional approach.

Identifying Statistically Significant Gene-Sets by Gene Set Enrichment Analysis Using Fisher Criterion (Fisher Criterion을 이용한 Gene Set Enrichment Analysis 기반 유의 유전자 집합의 검출 방법 연구)

  • Kim, Jae-Young;Shin, Mi-Young
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.45 no.4
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    • pp.19-26
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    • 2008
  • Gene set enrichment analysis (GSEA) is a computational method to identify statistically significant gene sets showing significant differences between two groups of microarray expression profiles and simultaneously uncover their biological meanings in an elegant way by employing gene annotation databases, such as Cytogenetic Band, KEGG pathways, gene ontology, and etc. For the gone set enrichment analysis, all the genes in a given dataset are first ordered by the signal-to-noise ratio between the groups and then further analyses are proceeded. Despite of its impressive results in several previous studies, however, gene ranking by the signal-to-noise ratio makes it difficult to consider highly up-regulated genes and highly down-regulated genes at the same time as the candidates of significant genes, which possibly reflect certain situations incurred in metabolic and signaling pathways. To deal with this problem, in this article, we investigate the gene set enrichment analysis method with Fisher criterion for gene ranking and also evaluate its effects in Leukemia related pathway analyses.

A Generic Multi-Level Algorithm for Prioritized Multi-Criteria Decision Making

  • G., AlShorbagy;Eslam, Hamouda;A.S., Abohamama
    • International Journal of Computer Science & Network Security
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    • v.23 no.1
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    • pp.25-32
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    • 2023
  • Decision-making refers to identifying the best alternative among a set of alternatives. When a set of criteria are involved, the decision-making is called multi-criteria decision-making (MCDM). In some cases, the involved criteria may be prioritized by the human decision-maker, which determines the importance degree for each criterion; hence, the decision-making becomes prioritized multi-criteria decision-making. The essence of prioritized MCDM is raking the different alternatives concerning the criteria and selecting best one(s) from the ranked list. This paper introduces a generic multi-level algorithm for ranking multiple alternatives in prioritized MCDM problems. The proposed algorithm is implemented by a decision support system for selecting the most critical short-road requests presented to the transportation ministry in the Kingdom of Saudi Arabia. The ranking results show that the proposed ranking algorithm achieves a good balance between the importance degrees determined by the human decision maker and the score value of the alternatives concerning the different criteria.

New Method for Preference Measurement in Ranking-based Conjoint Analysis (순위기반 컨조인트분석에서 선호도측정을 위한 새로운 방법)

  • Kim, Bu-Yong
    • The Korean Journal of Applied Statistics
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    • v.27 no.2
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    • pp.185-195
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    • 2014
  • Ranking-based conjoint analysis is widely used in various fields such as marketing research. While the ranking-based conjoint affords several advantages over the rating-based or choice-based conjoint, it has a serious shortcoming that respondents have much difficulty in ranking the product profiles in order of preference when many profiles are involved. This article suggests a new method for the preference measurement to improve the response efficiency. The method employs the concept of ranking sets that let the respondent evaluate a small number of profiles at a time. Through the proposed method, preference rankings of profiles obtained from each ranking set are aggregated to generate overall rankings. The balanced incomplete block design is expanded and transformed to the dual design in order to construct well-balanced ranking sets that can accommodate a large number of profiles. The proposed method is applied to the analysis of consumer preferences for perfume-for-women.

Statistical Method of Ranking Candidate Genes for the Biomarker

  • Kim, Byung-Soo;Kim, In-Young;Lee, Sun-Ho;Rha, Sun-Young
    • Communications for Statistical Applications and Methods
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    • v.14 no.1
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    • pp.169-182
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    • 2007
  • Receive operating characteristic (ROC) approach can be employed to rank candidate genes from a microarray experiment, in particular, for the biomarker development with the purpose of population screening of a cancer. In the cancer microarray experiment based on n patients the researcher often wants to compare the tumor tissue with the normal tissue within the same individual using a common reference RNA. Ideally, this experiment produces n pairs of microarray data. However, it is often the case that there are missing values either in the normal or tumor tissue data. Practically, we have $n_1$ pairs of complete observations, $n_2$ "normal only" and $n_3$ "tumor only" data for the microarray. We refer to this data set as a mixed data set. We develop a ROC approach on the mixed data set to rank candidate genes for the biomarker development for the colorectal cancer screening. It turns out that the correlation between two ranks in terms of ROC and t statistics based on the top 50 genes of ROC rank is less than 0.6. This result indicates that employing a right approach of ranking candidate genes for the biomarker development is important for the allocation of resources.

A Bayesian Approach for Solving Goal Programs Having Probabilistic Priority Structure

  • Suh Nam-Soo
    • Journal of the military operations research society of Korea
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    • v.15 no.1
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    • pp.44-53
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    • 1989
  • This paper concerns with the case of having a goal program with no preassigned deterministic ranking for the goals. The priority ranking in this case depends on the states of nature which are random variables. The Bayesian approach is performed to obtain the nondominated set of rankings.

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A Ranking Method for Type-2 Fuzzy Values (타입-2 퍼지값의 순위결정)

  • Lee, Seung-Soo;Lee, Kwang-H.
    • Journal of the Korean Institute of Intelligent Systems
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    • v.12 no.4
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    • pp.341-346
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    • 2002
  • Type-1 fuzzy set is used to show the uncertainty in a given value. But there are many situations where it needs to be extended to type-2 fuzzy set because it can be also difficult to determine the crisp membership function itself. Type-2 fuzzy systems have the advantage that they are more expressive and powerful than type-1 fuzzy systems, but they require many operations defined for type-1 fuzzy sets need to be extended in the domain of type-2 fuzzy sets. In this paper, comparison and ranking methods for type-2 fuzzy sets are proposed. It is based on the satisfaction function that produces the comparison results considering the actual values of the given type-2 fuzzy sets with their possibilities. Some properties of the proposed method are also analyzed.

Ranking Candidate Genes for the Biomarker Development in a Cancer Diagnostics

  • Kim, In-Young;Lee, Sun-Ho;Rha, Sun-Young;Kim, Byung-Soo
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2004.11a
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    • pp.272-278
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    • 2004
  • Recently, Pepe et al. (2003) employed the receiver operating characteristic (ROC) approach to rank candidate genes from a microarray experiment that can be used for the biomarker development with the ultimate purpose of the population screening of a cancer, In the cancer microarray experiment based on n patients the researcher often wants to compare the tumor tissue with the normal tissue within the same individual using a common reference RNA. This design is referred to as a reference design or an indirect design. Ideally, this experiment produces n pairs of microarray data, where each pair consists of two sets of microarray data resulting from reference versus normal tissue and reference versus tumor tissue hybridizations. However, for certain individuals either normal tissue or tumor tissue is not large enough for the experimenter to extract enough RNA for conducting the microarray experiment, hence there are missing values either in the normal or tumor tissue data. Practically, we have $n_1$ pairs of complete observations, $n_2$ 'normal only' and $n_3$ 'tumor only' data for the microarray experiment with n patients, where n=$n_1$+$n_2$+$n_3$. We refer to this data set as a mixed data set, as it contains a mix of fully observed and partially observed pair data. This mixed data set was actually observed in the microarray experiment based on human tissues, where human tissues were obtained during the surgical operations of cancer patients. Pepe et al. (2003) provide the rationale of using ROC approach based on two independent samples for ranking candidate gene instead of using t or Mann -Whitney statistics. We first modify ROC approach of ranking genes to a paired data set and further extend it to a mixed data set by taking a weighted average of two ROC values obtained by the paired data set and two independent data sets.

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