• 제목/요약/키워드: Adverse Selection

검색결과 144건 처리시간 0.024초

이익조정과 스톡옵션이 자사주 매입 공시효과에 미치는 영향 (Effect of Earnings Management and Stock Options on the Disclosure Effect of Share Repurchases)

  • 김경순;김유진;김홍렬
    • 아태비즈니스연구
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    • 제12권3호
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    • pp.343-359
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    • 2021
  • Purpose - The purpose of this paper is to investigate the relationship between earnings management and the disclosure effect of share repurchase. In addition, we analyze whether the relationship between earnings management and share repurchase is affected by executive stock options. Design/methodology/approach - We calculate the discretionary accrual amount for the year immediately preceding the share repurchase and the cumulative excess return around the announcement of the share repurchase, and examine the relationship between the two by regression analysis. Findings - We confirmed a negative relationship between discretionary accrual in the year immediately preceding the share repurchase and the market response to the share repurchase disclosure. In particular, it was found that the negative relationship between discretionary accrual and stock price return on share repurchase announcement was found to decrease in companies to which executive stock options were granted. Research implications or Originality - When uncertainties exist in the motives for share repurchase, we find that earnings management and executive stock options can be useful tools for reducing the adverse selection risk inherent in share repurchase announcements.

The Effect of Inaccurate Quality Signaling under Information Asymmetry

  • Seung Huh
    • 아태비즈니스연구
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    • 제14권1호
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    • pp.231-246
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    • 2023
  • Purpose - This study attempts to provide a new theoretical perspective on the quality signaling and its impact on a market under information asymmetry, focusing on how the accuracy and the cost of quality signaling affect sellers' and buyers' profit, suggesting appropriate designs of quality signaling methods which mitigates information asymmetry. Design/methodology/approach - In order to examine the effect of quality signaling on strategic interactions within the market, we establish an analytic model where market outcomes are determined by seller's quality claim and price, and buyers are risk-neutral. By investigating this analytic model through relevant game trees, we find the subgame perfect Nash equilibria of the market and predict related market outcomes based on sellers' quality signaling strategy. Findings - Our analytic model shows counterintuitive results that seller profit will be the lowest with inaccurate quality signaling and the highest with no quality signaling, mostly due to the certification cost. Consequently, sellers should proceed with caution if the quality signaling is less than accurate, as it may backfire. We believe that this is due to the fact that the inaccuracy of quality signaling causes some confusion and uncertainty in both sellers and buyers' decision to maximize profit, making it hard for sellers to predict buyers' behavior. Research implications or Originality - Although the sources and types of quality signaling errors have been investigated in the literature, there has not been satisfactory understanding regarding how inaccuracy of quality certification affects specific market outcomes. We expect that our theoretical model would provide important implications on how to utilize quality signaling to solve adverse selection issues in markets under information asymmetry.

Electroacupuncture Treatment for Post-Stroke Foot Drop: A Systemic Review of Randomized Controlled Trials

  • Hye Jeong Jo;Go Eun Chae;Hyun Woo Kim;Young Jin Lee;Ahra Koh;Ji Eun Choi;So Jung Kim;Woo Young Kim
    • Journal of Acupuncture Research
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    • 제41권2호
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    • pp.75-86
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    • 2024
  • A review of randomized controlled trials (RCTs) using electroacupuncture (EA) to treat patients with foot drop was performed to analyze the effectiveness of EA for this condition. Relevant studies (n = 183) from 7 databases (Cochrane Library, Excerpta Medica Database, PubMed, China National Knowledge Infrastructure, Korean Studies Information Service System, Research Information Sharing Service, and Oriental Medicine Advanced Searching Integrated System) were selected based on the inclusion and exclusion criteria, and 12 RCTs met the selection criteria. In all 12 studies, EA showed significantly positive changes. In most indicators, positive changes were observed in the EA group compared with that in the control group. Significant increases were confirmed in muscle strength-related indicators such as the Fugl-Meyer motor scale, surface electromyography, active range of motion, and gait-related indicators such as the Tinetti score, maximum walking speed, and Berg balance scale. No notable adverse events were reported. EA is suggested as an effective treatment for post-stroke foot drop; however, more RCTs are required.

참여 지분형 계약거래를 통한 양식산업 금융지원 연구 (Research on Financing the Aquaculture Industry through Participatory Equity Contracting)

  • 이화용;한병석;강형구
    • 수산경영론집
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    • 제54권4호
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    • pp.47-64
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    • 2023
  • The development potential of the aquaculture industry is very high, but there is no financial support for investment except for the government, policy funds, fishery funds, etc. Therefore, we would like to propose a contract transaction in the aquaculture industry. This refers to a forward contract between a producer (fish farmer) and a buyer (mainly a processor or marketer) that stipulates the production and supply of fish products at a predetermined price, but it also refers to an "equity participation type" contract in which both producers and buyers can participate. In other words, it is a model in which part of the fish farm is produced in a way that meets the conditions of the buyer, and part is produced by the producer. This study aims to establish the basic contract trading process. It provides an academic approach to prevent adverse selection and moral hazard due to information asymmetry. It also provides an idea to converge the aquaculture industry with the financial industry using Pecking Order theory. By doing so, we have made it possible for venture capitalists to invest with confidence and provided a process for investors to resolve their concerns, paving the way for the aquaculture industry and the financial industry to develop together.

악성 간문부 담도 폐쇄에서 내시경 배액술의 최근 경향 (Trends of Endoscopic Palliation for Advanced Malignant Hilar Biliary Obstruction)

  • 이태훈
    • The Korean Journal of Medicine
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    • 제99권1호
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    • pp.4-10
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    • 2024
  • Malignant hilar biliary obstruction (MHO), an aggressive type of perihilar biliary obstruction caused by cholangiocarcinoma, gallbladder cancer, or other metastatic malignancies, has a poor prognosis. Surgical resection is the only curative treatment for biliary malignancies. However, most patients with MHO cannot undergo surgery upon presentation because of their advanced inoperable state or poor performance resulting from old age or comorbid diseases. Therefore, palliative biliary drainage is required to improve symptomatic jaundice and quality of life. Preoperative biliary drainage is controversial in resectable cases of MHO. Preoperative biliary drainage should be considered according to specific selection criteria. Palliative drainage is currently the mainstay of symptomatic treatment. Compared with percutaneous access, primary endoscopic palliation using plastic or metal stents has recently shown higher technical feasibility and clinical success without increasing the frequency of adverse events, even in high-degree MHO. However, the use of stents still has numerous limitations, including challenges in determining the optimal type of stent, number of stents, deployment method, and additional local therapies. Therefore, this report presents the current optimal endoscopic drainage status for MHO based on recent guidelines and published literature.

조기난소부전의 한약 치료에 대한 무작위 대조군 임상 연구 고찰 (Review of Randomized controlled Trials on Korean Herbal Medicine Treatment for Premature Ovarian Insufficiency)

  • 송지윤;김동철
    • 대한한방부인과학회지
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    • 제37권3호
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    • pp.85-106
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    • 2024
  • Objectives: This study was performed to analyze randomized controlled trial, which studied the effect of korean herbal medicine on premature ovarian insufficiency. Methods: Researchers searched for randomized controlled trial of based on korean herbal medicine and premature ovarian insufficiency. The paper search was conducted through 7 online databases on April 20, 2024. Results: 12 studies were included after selection and exclusion criteria. 4 studies compared herbal medicine with hormone replacement therapy or placebo. 8 studies compared combined treatment of herbal medicine and hormone replacement therapy, with hormone replacement therapy alone. All studies reported significant improvement on hormone, antral follicle count (AFC), total effective rate and associated symptoms. There were no serious adverse effects. Conclusions: This study suggests that herbal medicine has benefit for treating symptoms and ovarian function of premature ovarian insufficiency. For reliable evidence, further research on pregnancy or long-term follow-up is needed.

Selection signature reveals genes associated with susceptibility loci affecting respiratory disease due to pleiotropic and hitchhiking effect in Chinese indigenous pigs

  • Xu, Zhong;Sun, Hao;Zhang, Zhe;Zhang, Cheng-Yue;Zhao, Qing-bo;Xiao, Qian;Olasege, Babatunde Shittu;Ma, Pei-Pei;Zhang, Xiang-Zhe;Wang, Qi-Shan;Pan, Yu-Chun
    • Asian-Australasian Journal of Animal Sciences
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    • 제33권2호
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    • pp.187-196
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    • 2020
  • Objective: Porcine respiratory disease is one of the most important health problems causing significant economic losses. To understand the genetic basis for susceptibility to swine enzootic pneumonia (EP) in pigs, we detected 102,809 single nucleotide polymorphisms in a total of 249 individuals based on genome-wide sequencing data. Methods: Genome comparison of susceptibility to swine EP in three pig breeds (Jinhua, Erhualian, and Meishan) with two western lines that are considered more resistant (Duroc and Landrace) using cross-population extended haplotype homozygosity and F-statistic (FST) statistical approaches identified 691 positively selected genes. Based on quantitative trait loci, gene ontology terms and literature search, we selected 14 candidate genes that have convincible biological functions associated with swine EP or human asthma. Results: Most of these genes were tested by several methods including transcription analysis and candidate genes association study. Among these genes: cytochrome P450 1A1 and catenin beta 1 (CTNNB1) are involved in fertility; transforming growth factor beta receptor 3 plays a role in meat quality traits; Wnt family member 2, CTNNB1 and transcription factor 7 take part in adipogenesis and fat deposition simultaneously; plasminogen activator, urokinase receptor (completely linked to AXL receptor tyrosine kinase, r2 = 1) plays an essential role in the successful ovulation of matured oocytes in pigs; colipase like 2 (strongly linked to SAM pointed domain containing ETS transcription factor, r2 = 0.848) is involved in male fertility. Conclusion: These adverse genes susceptible to swine EP may be selected while selecting for economic traits (especially reproduction traits) due to pleiotropic and hitchhiking effect of linked genes. Our study provided a completely new point of view to understand the genetic basis for susceptibility or resistance to swine EP in pigs thereby, provides insight for designing sustainable breed selection programs. Finally, the candidate genes are crucial due to their potential roles in respiratory diseases in a large number of species, including human.

Report of the 3rd Japan-Korea Workshop on Acupuncture and EBM;Protocol development for the acupuncture trial on the osteoarthritis of the knee

  • Jang, Jun-Hyouk;Kenji, Kawakita;Hahn, Seo-Kyung;Park, Hi-Joon;Lee, Seung-Deok;Kim, Yong-Suk;Norihito, Takahashi;Toshiyuki, Shichidou;Kazunori, Itoh;Eiji, Sumiya;Eiji, Furuya;Hitoshi, Yamashita;Hiroshi, Tsukayama
    • Journal of Acupuncture Research
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    • 제23권6호
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    • pp.239-254
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    • 2006
  • The 3rd Japan-Korea Workshop on Acupuncture and EBM was held at Kanazawa on June $16^{th}$. From Korea team, 4 papers were presented. Dr. Hahn introduced a new approach of data analysis on series of n-of-1 trials using the Bayesian statistics. It offered important information for the future n-of-1 trials. Dr. Park clearly demonstrated the significance of various sham devices proposed and stressed the importance of research questions when we choose the control intervention in RCT. Dr. Lee reported the results of survey in Korean Medical Doctors (KMD) for their point selection and techniques to the distal and local points. Dr. Kim presented the results of face to face survey on the KMD with 28 items for acupuncture treatment on the knee OA. Finally, a draft of protocol was introduced by Dr. Kim. The title was "multi-center, a randomized, single blinded, two arms, parallel-group study to compare the effectiveness and safety of 'individualized acupuncture' and 'standardized minimal acupuncture' in Korean and Japanese patients with knee osteoarthritis (Phase IV)". From Japan team, 7 speakers presented their comments and proposals on the protocol. Dr. Takahashi introduced several issues regarding n-of-1 trials and pointed out the importance of obtaining generalizability from n-of-1 trials. Dr. Shichidou pointed the importance of research design, selection of outcome measures and reduction of biases. Dr. Itoh presented the results of point selection for the knee OA based on the literature survey. Dr. Sumiya introduced several differences between KMD and Japanese acupuncturists based on the questionnaire used in KMD survey. Dr. Furuya demonstrated a result of press tack needle and its sham device on shoulder stiffness. Dr. Yamashita introduced the results of literature survey regarding adverse events occurred by acupuncture on knee OA. Dr.Tsukayama stressed the importance of responsibility of Institutional Review Board (IRB) for the conduction of clinical trials. After several issues were discussed, the need of continued meeting for final protocol development was agreed, then the workshop was closed.

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Zoning Permanent Basic Farmland Based on Artificial Immune System coupling with spatial constraints

  • Hua, Wang;Mengyu, Wang;Yuxin, Zhu;Jiqiang, Niu;Xueye, Chen;Yang, Zhang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권5호
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    • pp.1666-1689
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    • 2021
  • The red line of Permanent Basic Farmland is the most important part in the "three-line" demarcation of China's national territorial development plan. The scientific and reasonable delineation of the red line is a major strategic measure being taken by China to improve its ability to safeguard the practical interests of farmers and guarantee national food security. The delineation of Permanent Basic Farmland zoning (DPBFZ) is essentially a multi-objective optimization problem. However, the traditional method of demarcation does not take into account the synergistic development goals of conservation of cultivated land utilization, ecological conservation, or urban expansion. Therefore, this research introduces the idea of artificial immune optimization and proposes a multi-objective model of DPBFZ red line delineation based on a clone selection algorithm. This research proposes an objective functional system consisting of these three sub-objectives: optimal quality of cropland, spatially concentrated distribution, and stability of cropland. It also takes into consideration constraints such as the red line of ecological protection, topography, and space for major development projects. The mathematical formal expressions for the objectives and constraints are given in the paper, and a multi-objective optimal decision model with multiple constraints for the DPBFZ problem is constructed based on the clone selection algorithm. An antibody coding scheme was designed according to the spatial pattern of DPBFZ zoning. In addition, the antibody-antigen affinity function, the clone mechanism, and mutation strategy were constructed and improved to solve the DPBFZ problem with a spatial optimization feature. Finally, Tongxu County in Henan province was selected as the study area, and a controlled experiment was set up according to different target preferences. The results show that the model proposed in this paper is operational in the work of delineating DPBFZ. It not only avoids the adverse effects of subjective factors in the delineation process but also provides multiple scenarios DPBFZ layouts for decision makers by adjusting the weighting of the objective function.

Prostatic Artery Embolization for Lower Urinary Tract Symptoms via Transradial Versus Transfemoral Artery Access: Single-Center Technical Outcomes

  • Ryun Gil;Dong Jae Shim;Doyoung Kim;Dong Hwan Lee;Jung Jun Kim;Jung Whee Lee
    • Korean Journal of Radiology
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    • 제23권5호
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    • pp.548-554
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    • 2022
  • Objective: To evaluate the safety and feasibility of prostatic artery embolization (PAE) via transradial access (TRA) compared with transfemoral access (TFA). Materials and Methods: This retrospective study included 53 consecutive men with lower urinary tract symptoms (LUTS) who underwent PAE between September 2018 and September 2021. Thirty-one patients (mean age ± standard deviation: 70.6 ± 8.4 years) were treated with TFA, including 14 patients treated before adopting TRA. Since December 2019, TRA has also been attempted with the procedure's selection criteria of patent carpal circulation and a height ≤ 172 cm, with 22 patients treated via TRA (69.1 ± 9.6 years). Parameters of technical success (defined as successful bilateral embolization), clinical success (defined as LUTS improvement), procedural time, radiation dose, and adverse events were compared between the two groups using the Fisher's exact test, independent sample t test, Wilcoxon signed-rank test, or Mann-Whitney test. Results: All patients received at least one-side PAE. Technical success of PAE was achieved in most patients (TRA, 21/22; TFA, 30/31; p > 0.999). No technical problem-related conversion from TRA to TFA occurred. The clinical success rate was 85% (11/13) in patients with TRA, and 89% (16/18) in patients with TFA for follow-up > 2 weeks post-PAE (median, 3 months) (p > 0.999). The median procedure time was similar in both groups (TRA, 81 minutes vs. TFA, 94 minutes; p = 0.570). No significant dose differences were found between the TRA and TFA groups in the dose-area product (median Gycm2, 95 [range, 44-255] for TRA and 84 [34-255] for TFA; p = 0.678) or cumulative air kerma (median mGy, 609 [236-1584] for TRA and 634 [217-1594] for TFA; p = 0.551). No major adverse events occurred in either of the groups. Conclusion: PAE via TRA is a safe and feasible method comparable to conventional TFA. It can be safely implemented by selecting patients with patent carpal circulation and adequate height.