CEO Overconfidence or Private Information? Evidence from U.S. Property-Liability Insurance Companies

[[abstract]]This paper uses conventional measures of CEO overconfidence: option holdings-based and net stock purchase-based measures to examine the impact of CEOs who hold firm-specific risk on insurer’s risk-taking and firm performance. We focus on the insurance industry because using reinsurance demand as a proxy for risk-taking provides a precise measurement of CEO’s risk-taking. We find that the two CEO overconfidence measures are negatively associated with insurer’s risk-taking and positively related to firm performance. Our findings suggest that it may not be CEO overconfidence, but rather the private information and the intention to control the company’s risk that drive our results.[[notice]]補正完

Building and Adaptive Learning Mechanism to Assist eLearning Students

Intelligent Tutoring System has been developed to provide an individualized learning environment in order to prompt learning interests and learning efficiency for online education. In this paper, based on the concept of intelligent tutoring system and educational product function, we establish a distance learning environment where students receive learning contents that best suit their needs. In this environment, we adopt clustering theory by utilizing SOM algorithm in the system and analyze the relationship between students’ personal background, interests and learning result. The workload of instructors is relieved and student’s learning ability and interests are considered in providing adequate learning contents which lead to more effective teaching effect and learning result. The proposed system is applied to the construction of an online 3D virtual museum

Ownership Structure and Reinsurance Decisions: Evidence from the Property Casualty Insurance Industry in China

[[abstract]]This study examines the impact of ownership structure on reinsurance decisions in the Chinese property casualty insurance industry. The evidence shows that foreign insurers have higher reinsurance demand than domestic insurers. Specifically, foreign insurers are more likely to purchase volunteer reinsurance. More important, foreign insurers are associated with a higher percentage of facultative reinsurance ratios than domestic insurers. Implementing the compulsory reinsurance ratio in the Chinese insurance market before 2006 is inefficient. Finally, regulation of compulsory reinsurance ratio affected the reinsurance demand in 2006. For example, insurers with a 10 percent compulsory reinsurance ratio in 2004 had significantly different reinsurance demand from that of insurers without compulsory reinsurance after 2006. The overall results of this study indicate that ownership structure and other characteristics of firms’ significantly affect the demand for reinsurance.[[sponsorship]]淡江大學保險學系; 西南財經大學保險學院[[conferencetype]]兩岸[[conferencetkucampus]]台北校園[[conferencedate]]20131214~20131214[[booktype]]紙本[[iscallforpapers]]Y[[conferencelocation]]Taipei, Taiwa

Understanding Why Older Adults With Type 2 Diabetes Join Diabetes Online Communities: Semantic Network Analyses.

BackgroundAs individuals age, chronic health difficulties may disrupt physical and social well-being. Individuals can turn to online communities to interact with similar peers, which may help buffer negative effects resulting from health difficulties.ObjectiveThis study investigated the reasons that older adults join a diabetes online community to better understand the specific resources that are being sought.MethodsWe used semantic network analyses to categorize the reasons participants provided for joining a community during the sign-up process.ResultsThe most frequent reasons for joining were to seek information about their health condition, to help with self-management of health difficulties, for feelings of informational and social support, and for having a community with whom to share. Women were more likely to go online for sharing and companionship as well as for information and social support reasons, whereas men were more likely to go online for general information and self-management reasons.ConclusionsThis study shows the reasons older adults seek to join a diabetes online community: for increased information and support regarding chronic health difficulties. Practitioners may want to consider ways to promote access to online communities among their older patients as a source of health information and a resource to provide a sense of community

Identification of overexpressed cytokines as serum biomarkers of hepatitis C virus-induced liver fibrosis using bead-based flexible multiple analyte profiling

Hepatic inflammation is the stimulator to activate hepatic stellate cells (HSCs) and triggers fibrogenesis. Cytokines are produced during liver inflammation and maybe considered as liver fibrosis biomarker. The aim of this study was to investigate whether cytokines can be used as reliable biomarkers of liver fibrosis using flexible multi-analyte profiling (xMAP). A total of 61 chronic hepatitis C patients with different severity of liver fibrosis were enrolled. Liver biopsy was used as standard to assess the severity of fibrosis according to METAVIR classification. Afterward, 15 samples from healthy controls were analyzed and totally 50 cytokines were screened using flexible multi-analyte profiling to discover differential biomarkers. Finally, levels of protein expressions of individual stages of liver fibrosis were measured. In histological examination, the necroinflammatory score (histology activity index, HAI) was increased from F1 to F4 stage in hepatitis C virus (HCV) infected patients, indicating that inflammation was accompanied with the progression of liver fibrosis. Using flexible multi-analyte profiling, four serum cytokines, including IFN-α2 (p=0.023), GRO-α (p=0.013), SCF (p=0.047) and SDF-1α p=0.024), were identified under antibody specific recognition and elevated with HAI score. This study reveals the relationship between cytokines and liver fibrosis, and demonstrated that IFN-α2, GRO-α, SCF and SDF-1 α may be used as biomarkers to predict liver fibrosis. The overexpressed cytokines may play a role in the progression of liver fibrosis and deserves further investigation.Keywords: Cytokine, flexible multi-analyte profiling, hepatitis C virus, liver fibrosisAfrican Journal of Biotechnology Vol. 11(29), pp. 7535-7541, 29 April, 201

Automatic Cephalometric Landmark Detection on X-Ray Images Using Object Detection

We propose a new deep convolutional cephalometric landmark detection framework for orthodontic treatment. Our proposed method consists of two major steps: landmark detection using a deep neural network for object detection, and landmark repair to ensure one instance per landmark class. For landmark detection, we modify the loss function of the backbone network YOLOv3 to eliminate the constrains on the bounding box and incorporate attention mechanism to improve the detection accuracy. For landmark repair, a triangle mesh is generated from the average face to eliminate superfluous instances, followed by estimation of missing landmarks from the detected ones using Laplacian Mesh. Trained and evaluated on a public benchmark dataset from IEEE ISBI 2015 grand challenge, our proposed framework obtains comparable results compared to the state-of-the-art methods for cephalometric landmark detection, and demonstrates the efficacy of using a deep CNN model for accurate object detection of landmarks defined by only a single pixel location

Diagnosis of Polypoidal Choroidal Vasculopathy from Fluorescein Angiography Using Deep Learning

Purpose: To differentiate polypoidal choroidal vasculopathy (PCV) from choroidal neovascularization (CNV) and to determine the extent of PCV from fluorescein angiography (FA) using attention-based deep learning networks. Methods: We build two deep learning networks for diagnosis of PCV using FA, one for detection and one for segmentation. Attention-gated convolutional neural network (AG-CNN) differentiates PCV from other types of wet age-related macular degeneration. Gradient-weighted class activation map (Grad-CAM) is generated to highlight important regions in the image for making the prediction, which offers explainability of the network. Attention-gated recurrent neural network (AG-PCVNet) for spatiotemporal prediction is applied for segmentation of PCV. Results: AG-CNN is validated with a dataset containing 167 FA sequences of PCV and 70 FA sequences of CNV. AG-CNN achieves a classification accuracy of 82.80% at image-level, and 86.21% at patient-level for PCV. Grad-CAM shows that regions contributing to decision-making have on average 21.91% agreement with pathological regions identified by experts. AG-PCVNet is validated with 56 PCV sequences from the EVEREST-I study and achieves a balanced accuracy of 81.132% and dice score of 0.54. Conclusions: The developed software provides a means of performing detection and segmentation of PCV on FA images for the first time. This study is a promising step in changing the diagnostic procedure of PCV and therefore improving the detection rate of PCV using FA alone. Translational Relevance: The developed deep learning system enables early diagnosis of PCV using FA to assist the physician in choosing the best treatment for optimal visual prognosis

Discovery of serum biomarkers of alcoholic fatty liver in a rodent model: C-reactive protein

<p>Abstract</p> <p>Background</p> <p>Excessive consumption of alcohol contributes to alcoholic liver disease. Fatty liver is the early stage of alcohol-related liver disease. The aim of this study was to search for specific serological biomarkers of alcoholic fatty liver (AFL) compared to healthy controls, non-alcoholic fatty liver (NAFL) and liver fibrosis in a rodent model.</p> <p>Methods</p> <p>Serum samples derived from animals with AFL, NAFL, or liver fibrosis were characterized and compared using two-dimensional differential gel electrophoresis. A matrix-assisted laser desorption ionization-time of flight tandem mass spectrometer in conjunction with mascot software was used for protein identification. Subsequently, Western blotting and flexible multi-analyte profiling were used to measure the expressions of the putative biomarkers present in the serum of animals and clinical patients.</p> <p>Results</p> <p>Eight differential putative biomarkers were identified, and the two most differentiated proteins, including upregulated C-reactive protein (CRP) and downregulated haptoglobin (Hp), were further investigated. Western blotting validated that CRP was dramatically higher in the serum of AFL compared to healthy controls and other animals with liver disease of NAFL or liver fibrosis (<it>p </it>< 0.05). Moreover, we found that CRP and Hp were both lower in liver fibrosis of TAA-induced rats and clinical hepatitis C virus-infected patients.</p> <p>Conclusion</p> <p>The results suggest that increased levels of CRP are an early sign of AFL in rats. The abnormally elevated CRP induced by ethanol can be used as a biomarker to distinguish AFL from normal or otherwise diseased livers.</p