Forecasting financial and macroeconomic variables using data reduction methods: New empirical evidence

In this paper, we empirically assess the predictive accuracy of a large group of models based on the use of principle components and other shrinkage methods, including Bayesian model averaging and various bagging, boosting, LASSO and related methods Our results suggest that model averaging does not dominate other well designed prediction model specification methods, and that using a combination of factor and other shrinkage methods often yields superior predictions. For example, when using recursive estimation windows, which dominate other windowing approaches in our experiments, prediction models constructed using pure principal component type models combined with shrinkage methods yield mean square forecast error best models around 70% of the time, when used to predict 11 key macroeconomic indicators at various forecast horizons. Baseline linear models (which win around 5% of the time) and model averaging methods (which win around 25% of the time) fare substantially worse than our sophisticated nonlinear models. Ancillary findings based on our forecasting experiments underscore the advantages of using recursive estimation strategies, and provide new evidence of the usefulness of yield and yield-spread variables in nonlinear prediction specification

Autoimmune hemolytic anemia predominantly associated with IgA anti-E and anti-c.

A patient with warm autoimmune hemolytic anemia (AIHA) due to predominance of immunoglobulin A (IgA) with an Rh specificity, considered to be the first case in Korea, is described. A 13-year-old male patient with severe hemolytic anemia showed a weak reactivity (1+) in the direct antiglobulin test (DAT) by using anti-IgG antiglobulin reagent. This finding, however, could not fully explain the patient's severe AIHA. When anti-IgA reagent was used for the DAT, strong reactivity (4+) was observed and free anti-E and anti-c autoantibodies were also detected by anti-IgA and anti-IgG reagents. The patient's hemoglobin began to rise with the administration of steroids. Because RBCs coated with multiple types of immunoglobulins are associated with more severe hemolysis than those only with IgG, the DATs using anti-IgA and other reagents are needed for the correct diagnosis when the result of DAT is not compatible with patient's clinical manifestations

Forecasting Financial Stress Indices in Korea: A Factor Model Approach

We propose factor-based out-of-sample forecast models for Korea's financial stress index and its 4 sub-indices that are developed by the Bank of Korea. We extract latent common factors by employing the method of the principal components for a panel of 198 monthly frequency macroeconomic data after differencing them. We augment an autoregressive-type model of the financial stress index with estimated common factors to formulate out-of-sample forecasts of the index. Our models overall outperform both the stationary and the nonstationary benchmark models in forecasting the financial stress indices for up to 12-month forecast horizons. The first common factor that represents not only financial market but also real activity variables seems to play a dominantly important role in predicting the vulnerability in the financial markets in Korea

Recipients\u27 Perception of Service Quality, Satisfaction and their Behavioral Intention in Home-delivered Meal Program

This study was conducted to evaluate the recipients’ perception of service quality, satisfaction, and behavioral intention in home delivery program. Using structural equation modeling, this paper shows that food quality and volunteer’s attitude stimuli that enhance satisfaction. Results also suggest that satisfaction mediate the relationship between food quality and behavioral intentions. The results are theoretically and practically meaningful because they address the relationships among three types of perceived quality (food, kindness, and responsiveness), satisfaction, and behavioral intentions in the meals-on-wheels program

Investigating key attributes in experience and satisfaction of hotel customer using online review data

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. With the development of social media, customers are sharing their experiences, and it is rapidly spreading as a form of online review. That is why the online review has become a significant information source affecting customers\u27 purchase intention and behavior. Therefore, it is important to understand the customer\u27s experience shown in the online review in order to maintain sustainable customer satisfaction and loyalty. The purpose of this study is to investigate what are the key attributes and the structural relationship of those key attributes. To accomplish this purpose, a total of 6596 hotel reviews were collected from Google (google.com). A frequency analysis using text mining was performed to figure out the most frequently mentioned attributes. In addition, semantic network analysis, factor analysis, and regression analysis were applied to understand the experience and satisfaction of the hotel customer. As a result, the top 99 keywords were divided into four groups such as Intangible Service , Physical Environment , Purpose , and Location . The factor analysis reduced the dimension of the original 64 keywords to 22 keywords, and grouped them into five factors, which are Access , F&B (Food and Beverage) , Purpose , Tangibles , and Empathy . Based on these results, theoretical and practical implications for sustainable hotel marketing strategies are suggested

Teratogenicity and brain aromatase-induction of monosodium glutamate in estrogen-responsive mosaic transgenic zebra fish Danio rerio

Monosodium glutamate (MSG) has been used as a flavor enhancer for decades. It has various teratogenicity effects on tested animals but has not been examined in zebra fish model to date. This experiment was conducted to study the teratogenic effects of MSG on wild-type zebra fish embryos and also to study the estrogenic potential of MSG on the transient zebrafish embryos with a brain aromatase-based reporter gene. Different concentrations of MSG (0, 10, 50 and 100 μg/ml) were tested. Wild-type and transient embryos were exposed to the solutions at about 2 h post fertilization (hpf). Hatching and survival decreased in all treatments with significant difference (p < 0.05) at 50 and 100 μg/ml concentrations with control. Stunted skeletal structure was observed at 100 μg/ml treatment. At 96 hpf, MSG induced enhanced green fluorescence protein (EGFP) expression in the olfactory bulb at 100 μg/ml treatment. Various malformations were found in all treatments. The current results demonstrate that MSG or MSG-containing foods may harm the human offspring if they take it in a high dose. MSG in high concentration may disrupt the endocrine function. Zebra fish embryo with a brain aromatase-based reporter gene is a good model for the detection of estrogenic potential of any controversial chemical.Keywords: Monosodium glutamate (MSG), teratogenicity, aromatase, embryos, zebra fis

Association between harmful alcohol use and periodontal status according to gender and smoking

BACKGROUND: the aim of this study is to assess the association of harmful alcohol use based on the alcohol use disorders identification test (AUDIT) score with periodontal status according to gender and smoking in a representative sample of Korean adults. METHODS: This study analyzed 5,291 participants older than 19 years whose data of harmful alcohol use and periodontal status were available. Harmful alcohol use was defined by the WHO guidelines for the administration of AUDIT. The periodontal status was assessed by the Community Periodontal Index (CPI). Multivariate logistic regression analysis was performed with adjustment for socio-demographic variables, oral and general health behavior, oral health status and systemic conditions. All analyses considered a complex sampling design, and multivariate analysis was also performed in the subgroups. RESULTS: Multivariate logistic regression analysis revealed a marginal association between harmful alcohol use and higher CPI in the total sample. The adjusted odds ratio (OR) of harmful alcohol use was 1.16 (0.97 to 1.38) for higher CPI. Higher CPI was significantly associated with harmful alcohol use in men (OR: 1.28; 95% CI: 1.03-1.60) and non-smokers (OR: 1.29; 95% CI: 1.06-1.57). CONCLUSION: Periodontal status is significantly associated with harmful alcohol use in men and non-smokers in a representative sample of Korean adults

ねじれ積多様体上の共調和変換

We study the twisted product manifold with vanishing conharmonic curvature tensor which is invariant under the conharmonic transformation, and characterize the total space, base space and each fibre

Evaluation of the On-Campus Dining Service Using Importance-Performance Analysis

University foodservice is one of the largest sectors of the foodservice industry, and the college-student market is getting larger. Therefore, it is important that university foodservice needs to be monitored periodically and improved comprehensively in order to retain students as satisfied customers for on-campus foodservice. The objectives of the current study were to explore the importance and performance/satisfaction of on-campus dining service consumers, to investigate the importance-performance difference between patron and non-patron customers, and to examine the difference between gender groups. The study compared the respondents’ perceived importance and performance ratings of the dining service quality attributes using IPA. The IPA grid illustrated that food quality and sanitation fell into the Quadrant II (Keep up the Work); price into the Quadrant III (Low Priority); and service and environment into the Quadrant IV (Possible Overkill). However, according to IPA of comparison of patron versus non-patron groups and gender groups, the service attribute was allocated differently