2,443 research outputs found

    Contextual Linear Bandits under Noisy Features: Towards Bayesian Oracles

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    We study contextual linear bandit problems under uncertainty on features; they are noisy with missing entries. To address the challenges from the noise, we analyze Bayesian oracles given observed noisy features. Our Bayesian analysis finds that the optimal hypothesis can be far from the underlying realizability function, depending on noise characteristics, which is highly non-intuitive and does not occur for classical noiseless setups. This implies that classical approaches cannot guarantee a non-trivial regret bound. We thus propose an algorithm aiming at the Bayesian oracle from observed information under this model, achieving O~(dT)\tilde{O}(d\sqrt{T}) regret bound with respect to feature dimension dd and time horizon TT. We demonstrate the proposed algorithm using synthetic and real-world datasets.Comment: 30 page

    Experience in Close Relationships Scale-Short Version (ECR-S) Validation With Korean College Students

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    The goal of this study was to validate the Experience in Close Relationships Scale-Short version (ECR-S) in Korean college students. One item of the attachment avoidance subscale was deleted following confirmatory factor analysis. The results suggest that the ECR-S demonstrated acceptable internal consistency and construct validity.N

    Self-Focused Attention and Career Anxiety: The Mediating Role of Career Adaptability

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    The purpose of this study was to examine how 2 forms of self-focused attention, self-reflection and self-rumination, influence career anxiety. The authors hypothesized that the association between these 2 types of self-focused attention and career anxiety would be mediated by career adaptability on the basis of a career construction model of adaptation. The participants were 326 undergraduate students in South Korea. The results of this study supported the hypothesized mediation model by indicating significant indirect effects of self-reflection and self-rumination on career anxiety via career adaptability. The direct effect of self-rumination on career anxiety was significant (B = .44, p < .01), but the direct effect of self-reflection on career anxiety was not significant (B = -.05, p > .05). The authors discuss implications for counselors to help college students manage career anxiety by encouraging and supporting increased career adaptability. Future research to examine the cross-cultural validity of the current findings is needed.N

    Using the Theory of Planned Behavior to Predict Korean College Students' Help-Seeking Intention

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    When dealing with the mental health concerns of college students, access to professional mental health services is necessary to enable early identification and prevention of severe mental health issues. Accordingly, this study used the theory of planned behavior (TPB) as a theoretical framework to determine the predictors of help-seeking intentions among college students in Korea. The authors developed a TPB questionnaire to measure attitudes, subjective norms, behavioral control, and intentions for seeking help and subsequently validated it via the confirmatory factor analysis (CFA). The authors considered mental health condition as a pre-existing factor that influences TPB variables. In addition, they deemed knowledge of professional mental health services as a factor influencing perceived behavioral control regarding help-seeking behavior among Korean college students. The research hypotheses were stated as follows: (H1) mental health conditions would influence TPB variables, which would in turn influence their intentions to seek help, and (H2) knowledge about professional mental health services would influence perceived behavioral control. With 300 undergraduate and graduate students, our results confirmed that mental health condition and knowledge about professional mental health services were associated with TPB variables, and all of the TPB variables we examined predicted intention to seek help.N

    Cross-Sectional and Longitudinal Tests of Social Cognitive Model of Well-Being in Korean College Students

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    This study examined the cross-cultural utility of a modified social cognitive model of academic and life satisfaction (Lent & Brown, 2008) by adding independent and interdependent self-construals with Korean college students in a cross-sectional (Study 1) and a longitudinal design (Study 2). In Study 1, 604 participants completed measures of academic self-efficacy, outcome expectations, goal progress, environmental support, positive affect, academic satisfaction, life satisfaction, and self-construals. In Study 2, 171 participants completed the same measures at two time points with a 15-week interval. Results of Study 1 indicated that the modified model provided a good fit to the data and that 21 out of 25 of the hypothesized paths were significant. In Study 2, the bidirectional model, which included three theorized sets of reciprocal relations (i.e., academic satisfaction to life satisfaction, positive affect to both environmental support and self-efficacy, and self-efficacy to both outcome expectations and goal progress) demonstrated an optimal fit to the data. Overall, the findings of the present study provide evidence for the validity of the modified social cognitive well-being model in Korean populations.N

    Immunotherapy for NAFLD and NAFLD-related hepatocellular carcinoma

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    The progression of non-alcoholic fatty liver disease (NAFLD), the most common liver disease, leads to non-alcoholic steatohepatitis and hepatocellular carcinoma. Despite the increasing incidence and prevalence of NAFLD, its therapeutic and preventive strategies to lower the disease burden is limited. In recent years, immunotherapy, including anti-programmed cell death 1/programmed cell death 1 ligand 1 treatment, has emerged as a potential approach to reach satisfactory modulation for the progression of NAFLD and treatment of NAFLD-related hepatocellular carcinoma. However, the effectiveness of immunotherapy against NAFLD and NAFLD-related hepatocellular carcinoma is in the early phase and it is yet not advanced. In addition, conflicting results are being reported regarding the prognosis of patients with NAFLD-related hepatocellular carcinoma and high expression of programmed cell death 1/programmed cell death 1 ligand 1. Herein, this review will discuss and elucidate the attempts and underlying mechanisms of immunotherapy against NAFLD and NAFLD-related hepatocellular carcinoma

    Medial Meniscal Tears in Anterior Cruciate Ligament-Deficient Knees: Effects of Posterior Tibial Slope on Medial Meniscal Tear

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    PURPOSE: To evaluate the incidence of meniscal tears in patients with chronic anterior cruciate ligament (ACL)-deficient knees, and to determine the influence of posterior tibial slope (PTS) on medial meniscal tears in ACL-deficient knees. MATERIALS AND METHODS: We reviewed 174 patients (174 knees) with a mean age of 30.7 years who underwent ACL reconstruction for chronic ACL tears. We divided the patients into two groups: low group (135 knees with a PTS or =13degrees). RESULTS: The incidence of medial meniscus tears was 44% (77/174), and that of lateral meniscus tears was 35% (61/174). The mean PTS in patients with medial meniscal tears was 11.4degrees+/-3.0degrees, whereas that in patients without medial meniscal tears was 9.8degrees+/-2.4degrees. The incidence of meniscal tears was 57.8% (78/135) in the low group and 89.7% (35/39) in the high group (p or =13degrees is a risk factor for secondary medial meniscal tears in ACL-deficient knees. So, we suggest that PTS is one of the considerations for determining early ACL reconstruction to prevent secondary meniscal tears.ope
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