• Title/Summary/Keyword: subjective ratings

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Development of Objective Vehicle Ride Index (차량 승차감 평가지수 개발에 관한 연구)

  • 장한기;김승한;정용현;장진희
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.11a
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    • pp.450-454
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    • 2001
  • The aim of the study is to develope an objective index for the evaluation of vehicle ride comfort using the measured vehicle accelerations. The equation of the index was derived from the correlation analysis of subjective ratings on selected vehicles and the reduced measure of the vehicle motions. First whole procedure of from the measurements to the calculation of the perceptual vibration was developed. Test condition of both the vehicle speed and the road condition was selected so as to maximize the reliability of the index. This paper suggested the equation of the objective ride index on vibration harshness, of which expected error is about 0.3 in 10 scale of subjective rating at 95% of the significance level.

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Effective Object-Oriented Modeling and Design through Groupware (그룹웨어를 통한 효과적인 객체지향모델링 및 설계)

  • 김선욱;양문희
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.22 no.50
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    • pp.91-103
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    • 1999
  • This paper deals with effectiveness of Object-Oriented Modeling and Design(OOMD) through GroupSystems V which is a typical groupware or group decision support system(GDSS) to aid group work. Objective and subjective evaluations between traditional non-GDSS face-to-face group and GDSS-supported group have been performed in terms of modeling accuracy and subjective ratings, respectively. Experimental results indicate that the GDSS group shows much better performance than the traditional group in the realm of OOMD. In particular, when a modeling task is not simple or not structured, the former outperforms the latter. Based on the questionaire, the GDSS group feel more equal status and have less dominant voices than do the non-GDSS group. These facts show that GDSS can be used effectively for OOMD under Korean cultures.

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Corporate Bond Rating Using Various Multiclass Support Vector Machines (다양한 다분류 SVM을 적용한 기업채권평가)

  • Ahn, Hyun-Chul;Kim, Kyoung-Jae
    • Asia pacific journal of information systems
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    • v.19 no.2
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    • pp.157-178
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    • 2009
  • Corporate credit rating is a very important factor in the market for corporate debt. Information concerning corporate operations is often disseminated to market participants through the changes in credit ratings that are published by professional rating agencies, such as Standard and Poor's (S&P) and Moody's Investor Service. Since these agencies generally require a large fee for the service, and the periodically provided ratings sometimes do not reflect the default risk of the company at the time, it may be advantageous for bond-market participants to be able to classify credit ratings before the agencies actually publish them. As a result, it is very important for companies (especially, financial companies) to develop a proper model of credit rating. From a technical perspective, the credit rating constitutes a typical, multiclass, classification problem because rating agencies generally have ten or more categories of ratings. For example, S&P's ratings range from AAA for the highest-quality bonds to D for the lowest-quality bonds. The professional rating agencies emphasize the importance of analysts' subjective judgments in the determination of credit ratings. However, in practice, a mathematical model that uses the financial variables of companies plays an important role in determining credit ratings, since it is convenient to apply and cost efficient. These financial variables include the ratios that represent a company's leverage status, liquidity status, and profitability status. Several statistical and artificial intelligence (AI) techniques have been applied as tools for predicting credit ratings. Among them, artificial neural networks are most prevalent in the area of finance because of their broad applicability to many business problems and their preeminent ability to adapt. However, artificial neural networks also have many defects, including the difficulty in determining the values of the control parameters and the number of processing elements in the layer as well as the risk of over-fitting. Of late, because of their robustness and high accuracy, support vector machines (SVMs) have become popular as a solution for problems with generating accurate prediction. An SVM's solution may be globally optimal because SVMs seek to minimize structural risk. On the other hand, artificial neural network models may tend to find locally optimal solutions because they seek to minimize empirical risk. In addition, no parameters need to be tuned in SVMs, barring the upper bound for non-separable cases in linear SVMs. Since SVMs were originally devised for binary classification, however they are not intrinsically geared for multiclass classifications as in credit ratings. Thus, researchers have tried to extend the original SVM to multiclass classification. Hitherto, a variety of techniques to extend standard SVMs to multiclass SVMs (MSVMs) has been proposed in the literature Only a few types of MSVM are, however, tested using prior studies that apply MSVMs to credit ratings studies. In this study, we examined six different techniques of MSVMs: (1) One-Against-One, (2) One-Against-AIL (3) DAGSVM, (4) ECOC, (5) Method of Weston and Watkins, and (6) Method of Crammer and Singer. In addition, we examined the prediction accuracy of some modified version of conventional MSVM techniques. To find the most appropriate technique of MSVMs for corporate bond rating, we applied all the techniques of MSVMs to a real-world case of credit rating in Korea. The best application is in corporate bond rating, which is the most frequently studied area of credit rating for specific debt issues or other financial obligations. For our study the research data were collected from National Information and Credit Evaluation, Inc., a major bond-rating company in Korea. The data set is comprised of the bond-ratings for the year 2002 and various financial variables for 1,295 companies from the manufacturing industry in Korea. We compared the results of these techniques with one another, and with those of traditional methods for credit ratings, such as multiple discriminant analysis (MDA), multinomial logistic regression (MLOGIT), and artificial neural networks (ANNs). As a result, we found that DAGSVM with an ordered list was the best approach for the prediction of bond rating. In addition, we found that the modified version of ECOC approach can yield higher prediction accuracy for the cases showing clear patterns.

The Effect of Empathy induced by Positive Events on Subjective Value of Reward: Preliminary Study

  • Kim, Jong-Wan;Jung, Dae-Hyun;Eom, Ki-Min;Han, Kwang-Hee
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2009.11a
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    • pp.228-231
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    • 2009
  • Recent studies have focused on human empathic behavior regarding to physical, cognitive, and emotional aspects. Especially empathy is considered as a multidisciplinary study because of its wide application. However, majority of the studies have been focusing on empathy induced by negative emotion and physical pain. As a result, the purpose of this study, based on Loggia et al. (2008), is to investigate if empathy could be induced by positive events, and consequently if the positive empathy could increase subjective value of reward. According to the result of experiment which involved eight participants, we could confirm the inducement of empathy by positive events significantly; its power is not so strong though. However there was no interaction between empathy type (positive and no empathy) and whether the target received the reward or not. But if we would recruit more participants and additionally analyze correlation among trait/empathic state questionnaire, subjective ratings of the reward and emotion of the target, we suggest that this study would be valuable in that it could expand the empathy studies.

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Development and Evaluation of the Neck Supporter for Preventing Neck-related MSDs

  • Kong, Yong-Ku;Han, Jun-Goo
    • Journal of the Ergonomics Society of Korea
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    • v.30 no.2
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    • pp.297-302
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    • 2011
  • Many WMSDs(work-related-musculoskeletal disorders) have been reported in diverse industries and have also attracted much attention in recent years. Neck-related MSD is generally known as one of common WMSDs, especially it happens to workers who are working at the automobile assembly plants and/or shipyards. The awkward posture is considered as a main cause of neck-related MSDs. A neck supporter was developed to prevent neck-related MSDs, and 10 males were recruited to evaluate the newly developed neck supporter by measuring subjective discomfort ratings of whole body, shoulder, neck and neck-muscle activities. Muscle activities from four neck muscle groups(left/right sternocleidomastoid and upper/middle trapezius) were measured while simulating an automobile assembly task. Results showed that the neck supporter help to significantly improve subjective discomfort for whole-body, shoulder as well as neck body parts. The analyses of muscular activities also showed that the activities of left/right sternocleidomastoid muscles were statistically decreased with the neck supporter in this study. The muscle activities of upper/middle trapezius in case of wearing the neck supporter were not significantly different with the muscle activities in case of no-wearing the neck supporter. Overall findings verified that the neck supporter might help to prevent neck-related MSDs based on the current study.

Statistical Analysis of a Subjective QoE Assessment for VVoIP Applications

  • Cano, Maria-Dolores;Cerdan, Fernando;Almagro, Sergio
    • ETRI Journal
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    • v.32 no.6
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    • pp.843-853
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    • 2010
  • A successful deployment of multimedia applications over wireless environments entails improving the quality of service (QoS), not only from a technical point of view, but also considering the quality of experience (QoE) from the final user's perception. Although objective QoE measure models avoid the difficulties of subjective surveys, subjective QoE assessments are essential to understand the way users evaluate the QoS. In this work, we study the effect of a wide range of parameters on the QoE of VVoIP applications in a real wireless scenario. Through a complete statistical analysis of users' ratings, we identify the following facts. Although the use of VVoIP in wireless networks does not yet represent an advantage for users, there are great expectations for all applications under study, and with greater popularity comes higher expectations. It is easier for respondents to identify good behavior than poor behavior. Whereas the respondents' frequency of Internet use does not impact on the scores, respondents' gender does. Finally, the most determining parameters of quality from a user's perspective were instability, video quality, voice distortion, usefulness, and graphical interface.

Hand Assessment for Women's Spring-Fall Dress Fabrics(Part 1) - Development for the Subjective Hand Evaluation Scale - (여성용 춘추복지의 태에 관한 연구(제1보) -태의 주관적 평가척도 개발을 중심으로-)

  • 홍경희;김재숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.18 no.3
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    • pp.327-338
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    • 1994
  • KES-F system is widely used in hand evaluation, however, it has encountered some challenges, such as the overlapping of primary hand value, lack of predictability in case of women's thin dress, difficulties in communication due to complexity of primary hand expression and cultural differences in subjective evaluation. Therefore, this study was intended 1) to find out the Korean primary hand expressions(factors) of the overall concept of fabric hand associated with women's spring- fall dress fabrics, 2) to develope the fabric hand attributes of those fabrics and 3) to show whether there are any differences between Korean textile experts and non-experts in terms of the concept of fabric hand descriptors of hand attributes. Data base of hand descriptors were collected by extensive interview 60 experts and 10 non - experts using 110 spring-fall dress fabrics. Finally, hand of selected fabrics was assessed by 205 experts and 265 non-experts using 7-point scale of 26 descriptors based on the data base. Subjective ratings were analyzed by common factor analysis with varimax rotation. It was found that Korean primary hand expression indicated rather simple property, hence, did not equate exactly with Japanese experssion(e.g. koshi, shinayakasa, etc.) which contains several material properties. There were differences in stretch IE resilience, especially liveliness, between the judgement of non- ex- pert than to experts. Surface- related category was more important to non-experts than to experts. Slight differences were found between both groups in terms of preferred descriptors. Important descriptors as a rating scale were suggested.

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Experimental Study on Subjective Evaluation of Car Interior Sound Quality (승용차 내부소음의 음질평가 실험연구)

  • 최병호;아우구스트쉬크
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.11a
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    • pp.177-182
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    • 2003
  • This study is directed toward determining the number and characteristics of psychologically meaningful perceptual dimensions required for assessing the sound Ouaiity with respect to vehicle interior and/or exterior noises. and toward identifying the acoustical or psychoacoustical bases underlying the perception. By nonmetric MDS and clustring analysis of sound quality data sets on our own, of critical importance are two perceptual dimensions for which subjective verdicts can be interpreted as loudness and sharpness. The perceptual dimensions based upon similarity judgments could be accounted for 48% and 24% of the variance. each of which might be a match for the acoustic parameter "A-weighted maximum pressure level"(r= .85) and for the psychoacoustic parameter "sharpness" (r= .65), respectively. On the other hand, the perceptual dimensions based upon preference ratings could explain 66% and 10% of the variance. where the acoustic parameter "A-weighted maximum pressure leve"(r= .92) might be taken to be a best predictor, but sharpness appeared to be less suitable for the description of Preference behavior. Linked to the results, the problems of quantitative modelling of subjective sound quality evaluation and also of implementing corresponding cognitive combination rule for technical and industrial applications, say having "winner-sound qualify" according to preference criteria will be shortly in discussion.

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Effects of 8 weeks administration of Korean Panax ginseng extract on the mood and cognitive performance of healthy individuals

  • L., Reay J.;B., Scholey A.;O., Kennedy D.
    • Journal of Ginseng Research
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    • v.31 no.1
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    • pp.34-43
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    • 2007
  • Background: Previous research has suggested that single doses of a standardised Panax ginseng extract can decrease fasted blood-glucose levels and modulate cognitive performance in healthy young volunteers. The latter has generally been seen in terms of improved secondary memory performance. However, both the cognitive effects of chronic administration of ginseng and the potential modulation of working memory have received comparatively little research attention. Aims: The current double-blind, placebo-controlled, balanced cross-over study investigated the effects of 8-weeks administration of Korean ginseng extract (200 mg) on cognitive performance, gluco-regulatory parameters and ratings of subjective mood and 'quality of life'. Methods: 'Eighteen healthy young participants were assessed pre-dose and 3 hours post-dose on the mornings of Day 1, Day 29 and Day 57 of 8 week treatment regimens of both placebo and ginseng. A four-week placebo wash-out separated the treatment phases. Each assessment included the Cognitive Drug Research battery, computerised working memory tasks, and Bond-Lader mood scales. The WHO Quality of Life scale (WHOQOL-BREF) was completed once per visit. Gluco-regulatory parameters were assessed with assays of blood glucose, insulin and HbA1c. Results: Data from the 16 participants that completed the study showed that there were no significant, acute treatment related differences on Day 1 of treatment, or in gluco-regulatory parameters throughout the study. However, time related performance improvements were evident following chronic administration of ginseng on the '3-Back' and 'Corsi-block' computerised working memory tasks. Ginseng was also associated with an improved score on the 'social relations' subscale of the WHOQOL-100, and a significant shift on the 'calm' factor of the Bond-Lader mood scales (from calm/relaxed towards excited/tense). Conclusion: The results of the current study suggest that Korean ginseng extract can modulate working memory performance and subjective ratings of 'quality of life' and mood. Replication with a larger sample size may further elucidate the actions of this product.

The Comparisons of Eating-Related Index and Pre- and Post-Prandial Gut Hormone Patterns between Normal-Overweight and Obese Subjects of Taeemin (태음인 정상-과체중군과 비만군의 식이관련지표 및 식사 전후 Gut Hormone 비교연구)

  • Lee, Ji-Won;Park, Byung-Joo;Lee, Jun-Hee
    • Journal of Korean Medicine for Obesity Research
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    • v.14 no.1
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    • pp.36-45
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    • 2014
  • Objectives: The purpose of this studay was to compare the eating-related index and the patterns of pre- and post-prandial gut hormone level in normal-overweight and obese subjects of Taeemin population. Methods: We enrolled healthy male participants who were diagnosed with Taeeumin by Sasang Constitutional diagnosis and who were normal-overweight ($18.5kg/m^2{\leq}$body mass index [BMI)< $25kg/m^2$) or obese ($25.0kg/m^2{\leq}$BMI< $30kg/m^2$). Eating behavior and gastrointestinal problems were assessed by using standardized scale. Subjective appetite ratings using visual analogue scales and the profiling of serum levels of ghrelin and peptide YY (PYY) were assessed before and after a standard meal (6 time points: 30 minutes pre-prandial, immediately before meal, 15, 30, 60, and 120 minutes post-prandial). Results: Tewnty two healthy Taeeumin people classified as normal-overweight group or obese group are the final subjects. External eating score of Dutch eating behavior questionaire scores is higher in normal-overweight group than in obese group. The variations of subjective appetite ratings in obese group are smaller than in normal-overweight group. The pattern of ghrelin in normal-overweight group shows a high peak at 30 minutes post-prandial point, which is contrary to existing studies. The pattern of PYY in obese group decreases from 15 minutes post-prandial point and shows lower peak level, whereas in normal-overweight group shows increasing tendency from pre-prandial point until 30 minutes post-prandial point. Conclusions: There are differences in the eating-related index and the gut hormone patterns related to obesity.