• 제목/요약/키워드: Missing variables

검색결과 201건 처리시간 0.026초

Internet Marketing Strategy and Performance in the Korean Small Export Firms (한국 중소수출기업의 인터넷 마케팅 전략과 성과에 관한 연구)

  • Ko, Kyung-Sun
    • International Commerce and Information Review
    • /
    • 제4권1호
    • /
    • pp.107-128
    • /
    • 2002
  • In order to clarify the relationship between the Internet utilization of the Korean small export firms for export marketing and it's performance, first, a research model and hypothesis have been made on a theoretical basis. This research hypothesis has been examined through gathering survey data and a statistical analysis based on MANOVA. The conclusion, as well as the main point of this thesis, is that, in most cases, there was a significant statistical connection between the variables of export performances and Internet-utilized export marketing strategies, which are both based on the classical AIDA model of effective hierarchy of communication for sales and advertising. This conclusion brings forth a substantial topic as well as provides meaningful implications for the Korean small export firms when putting together a marketing strategy using the Internet. It is also hoped that this will come as a reference for other researchers henceforth. However, there is an issue of lack of representativeness when considering that the samples were chosen on the basis of the convenience sampling method. Another issue may be that a portion of the subjects were not related to actual trade, but were, in fact, Web masters who operated e-trade systems. Furthermore, there are also numerous problems of missing data, and 6 out of the 8 main hypotheses possessed the issue of fitness level with the data. Therefore, in order to enhance both the representative and fitness levels of the data of further research for this topic, future respondents will have to have special trade knowledge, as well as technical knowledge of e-trade. However, unless the Internet begins to greatly contribute to export marketing of corporations, this type of enterprising spirit by corporations in gathering suitable respondents will not surface. Although not used in examining the hypotheses of this particular thesis, the relationship between competitive and circumstantial variables, which were added to the upcoming survey, and export performances will soon be analyzed and announced in order to atone for some of the standards this thesis fell short of.

  • PDF

Relationship between usage of removable denture and depression in Korean adults with loss of multiple teeth: A cross-sectional study using the seventh Korea National Health and Nutrition Examination Survey (다수 치아를 상실한 한국 성인에서 가철성 의치의 장착 여부와 우울증의 연관성: 국민건강영양조사 제 7기 자료를 활용한 단면 연구)

  • Shim, Jaeseung;Lee, Younghoo;Hong, Seoung-Jin;Noh, Kwantae;Pae, Ahran;Kim, Hyeong-Seob;Kwon, Kung-Rock;Paek, Janghyun
    • The Journal of Korean Academy of Prosthodontics
    • /
    • 제59권1호
    • /
    • pp.1-10
    • /
    • 2021
  • Purpose: The purpose of this study is to evaluate the relationship between removable denture and depression. This study aims to investigate the relationship between depression and each group by dividing them into a group that were using removable dentures and a group that needed removable dentures but were not using removable dentures. Materials and methods: This study was conducted using raw data from the 7th Korea National Health and Nutrition Examination Survey (KNHNES). By using variables related to the state of the prosthesis and the need for prosthesis among oral examination data, the oral examination data were classified into two groups; group using removable denture and group in need of removable dentures. In addition, the variables of depression were classified into normal (0-4), mild depression (5-9), moderate depression (10-19), and severe depression (20-27) using the values of PHQ-9. For statistical analysis, logistic regression analysis was performed using SAS 9.4. Results: In the group in need of removable dentures, the risk of severe depression was statistically and significantly higher than the group using removable dentures. Conclusion: In patient who have lost multiple teeth, rehabilitation of the missing area with removable dental prosthesis is expected to decrease the occurrence of severe depression.

The Effect of Blood Nutrient Index on Depression (성인 여성의 혈액 영양소 지표가 우울지표에 미치는 영향)

  • Noh, Hyun Sun;Kim, Moon Ju
    • The Journal of the Korea Contents Association
    • /
    • 제21권2호
    • /
    • pp.248-261
    • /
    • 2021
  • The purpose of this study is that the blood nutrient indicator in adult women, is the depressive indicator. This study recruited 77 pre-menopausal women, and excluding missing values, 53 (mean age 44.2±6.5 years) blood indexes were statistically confirmed and then analyzed the effect of indexes on the Beck Depression Inventory. The Beck's Depression Inventory(BDI)'s average of the study subjects was 7.6±7.2, and most of the depression symptoms were within the normal range. Only two women were very serious and other two women were serious state. As a result of this study, 21 questions of BDI was classified into 5 sub-factors. Of these, 2 factors were considered physical depression, 1 factor was mood depression, 1 factor was cognitive depression, and 1 factor undecided. As a result of the correlation analysis, triglyceride, LDL(low density lipoprotein) cholesterol and potassium showed statistically significant positive relationship with depressive factors. On the other hand, HDL(high density lipoprotein) cholesterol, sodium and chloride ions showed negative relationship with depressive factors. When multiple regression analysis was performed. Considering the depression factors was dependent variable, and triglyceride, cholesterol, blood sugar, and ketone bodies was considered as independent variables. HDL(high density lipoprotein) cholesterol had a statistically significant negative effect on the depression factor 3. Considering the depression factors was dependent variable, and minerals were considered as independent variables. Potassium had a positive effect, and chloride ions had a negative effect on the depressive factor 3. This study was limited to 77 pre-menopausal women. In the future, post-menopausal women, men, and clinical neurological disorders group will be possible.

The Effect of Solidarity with Non-Cohabiting Children of the Elderly on Successful Aging (노인의 비동거 자녀와의 결속력이 성공적 노화에 미치는 영향)

  • Lee, Su-Jin;Hong, So-Hyoung
    • Journal of Convergence for Information Technology
    • /
    • 제11권7호
    • /
    • pp.47-56
    • /
    • 2021
  • This study a secondary data analysis study attempted to identify the factors influencing the successful aging of the elderly in Korea. Using the data of the 7th Aging Research Panel in 2018, 4,106 people over 65 years of age who had at least one non-living child and no missing values in the study variables were enrolled. Data were analyzed by frequency analysis, crossover analysis, independent sample t-test, and binary logistic regression analysis. The results of this study revealed that the factors affecting successful aging among elderly included age, the presence or absence of a spouse, education level, housing type, subjective health, exercise, alcohol drinking, and non-face-to-face contact frequency with non-cohabiting children, and the explanatory power of the variables was 24.1%. In order for the elderly to achieve successful aging, centering on child ties, the frequency of non-face-to-face contact, which can comfort the elderly's life and increase the satisfaction of life in a continuous relationship, is more important than having children live close and meet frequently. Based on this study, various strategies are needed for the successful aging of elderly people who are socially isolated due to concerns about COVID-19 infection.

A Study on the Development of a Fire Site Risk Prediction Model based on Initial Information using Big Data Analysis (빅데이터 분석을 활용한 초기 정보 기반 화재현장 위험도 예측 모델 개발 연구)

  • Kim, Do Hyoung;Jo, Byung wan
    • Journal of the Society of Disaster Information
    • /
    • 제17권2호
    • /
    • pp.245-253
    • /
    • 2021
  • Purpose: This study develops a risk prediction model that predicts the risk of a fire site by using initial information such as building information and reporter acquisition information, and supports effective mobilization of fire fighting resources and the establishment of damage minimization strategies for appropriate responses in the early stages of a disaster. Method: In order to identify the variables related to the fire damage scale on the fire statistics data, a correlation analysis between variables was performed using a machine learning algorithm to examine predictability, and a learning data set was constructed through preprocessing such as data standardization and discretization. Using this, we tested a plurality of machine learning algorithms, which are evaluated as having high prediction accuracy, and developed a risk prediction model applying the algorithm with the highest accuracy. Result: As a result of the machine learning algorithm performance test, the accuracy of the random forest algorithm was the highest, and it was confirmed that the accuracy of the intermediate value was relatively high for the risk class. Conclusion: The accuracy of the prediction model was limited due to the bias of the damage scale data in the fire statistics, and data refinement by matching data and supplementing the missing values was necessary to improve the predictive model performance.

Comparisons of Anxiety, Sexual Attitudes and Behaviors According to Smartphone Use and Contacts with Obscene Materials in University Students (대학생의 스마트 폰 사용 및 음란물 접촉에 따른 불안, 성 태도, 행동 비교)

  • Moon, Jong-Hoon;Jeon, Min-Jae;Lee, Chang-Hyung
    • Journal of Korea Entertainment Industry Association
    • /
    • 제13권5호
    • /
    • pp.203-213
    • /
    • 2019
  • The purpose of this study was to compare the anxiety, sexual attitudes, and sexual behavior according to smartphone use and contacts with obscene materials. 110 university students surveyed demographic characteristics, smartphone use, contacts with obscene materials, anxiety, sexual attitudes, and sexual behavior, and analyzed 102 questionnaires except missing and incomplete responses. The collected data were analyzed by independent t-test or chi-square test. Men were significantly more likely to have contacts with obscene materials, sexual attitudes, and sexual behavior than the women (p<.05). In type of residence, boarding room or lodging was significantly higher at time of smartphone use, anxiety, and sexual behaviors than the home (p<.05). There was no difference in variables according to religion (p>.05). There was no difference in variables according to the level of academic achievement (p>.05). Time of smartphone use over 3 hours was significantly higher for contacts of obscene materials, anxiety, and sexual attitudes and behaviors than less 3 hours (p<.05). Higher levels of time of contacts with obscene materials were significantly higher in anxiety and sexual behaviors than lower level (p<.05). The results of this study can be used as a basis for the development of intervention programs for those who are experiencing excessive smartphone use and contacts with obscene materials.

Multivariate Analysis of Predictive Factors for the Severity in Stable Patients with Severe Injury Mechanism (중증 손상 기전의 안정된 환자에서 중증도 예측 인자들에 대한 다변량 분석)

  • Lee, Jae Young;Lee, Chang Jae;Lee, Hyoung Ju;Chung, Tae Nyoung;Kim, Eui Chung;Choi, Sung Wook;Kim, Ok Jun;Cho, Yun Kyung
    • Journal of Trauma and Injury
    • /
    • 제25권2호
    • /
    • pp.49-56
    • /
    • 2012
  • Purpose: For determining the prognosis of critically injured patients, transporting patients to medical facilities capable of providing proper assessment and management, running rapid assessment and making rapid decisions, and providing aggressive resuscitation is vital. Considering the high mortality and morbidity rates in critically injured patients, various studies have been conducted in efforts to reduce those rates. However, studies related to diagnostic factors for predicting severity in critically injured patients are still lacking. Furthermore, patients showing stable vital signs and alert mental status, who are injured via a severe trauma mechanism, may be at a risk of not receiving rapid assessment and management. Thus, this study investigates diagnostic factors, including physical examination and laboratory results, that may help predict severity in trauma patients injured via a severe trauma mechanism, but showing stable vital signs. Methods: From March 2010 to December 2011, all trauma patients who fit into a diagnostic category that activated a major trauma team in CHA Bundang Medical Center were analyzed retrospectively. The retrospective analysis was based on prospective medical records completed at the time of arrival in the emergency department and on sequential laboratory test results. PASW statistics 18(SPSS Inc., Chicago, IL, USA) was used for the statistical analysis. Patients with relatively stable vital signs and alert mental status were selected based on a revised trauma score of more than 7 points. The final diagnosis of major trauma was made based on an injury severity score of greater than 16 points. Diagnostic variables include systolic blood pressure and respiratory rate, glasgow coma scale, initial result from focused abdominal sonography for trauma, and laboratory results from blood tests and urine analyses. To confirm the true significance of the measured values, we applied the Kolmogorov-Smirnov one sample test and the Shapiro-Wilk test. When significance was confirmed, the Student's t-test was used for comparison; when significance was not confirmed, the Mann-Whitney u-test was used. The results of focused abdominal sonography for trauma (FAST) and factors of urine analysis were analyzed using the Chi-square test or Fisher's exact test. Variables with statistical significance were selected as prognostics factors, and they were analyzed using a multivariate logistics regression model. Results: A total of 269 patients activated the major trauma team. Excluding 91 patients who scored a revised trauma score of less than 7 points, 178 patients were subdivided by injury severity score to determine the final major trauma patients. Twenty-one(21) patients from 106 major trauma patients and 9 patients from 72 minor trauma patients were also excluded due to missing medical records or untested blood and urine analysis. The investigated variables with p-values less than 0.05 include the glasgow coma scale, respiratory rate, white blood cell count (WBC), serum AST and ALT, serum creatinine, blood in spot urine, and protein in spot urine. These variables could, thus, be prognostic factors in major trauma patients. A multivariate logistics regression analysis on those 8 variables showed the respiratory rate (p=0.034), WBC (p=0.005) and blood in spot urine (p=0.041) to be independent prognostic factors for predicting the clinical course of major trauma patients. Conclusion: In trauma patients injured via a severe trauma mechanism, but showing stable vital signs and alert mental status, the respiratory rate, WBC count and blood in the urine can be used as predictable factors for severity. Using those laboratory results, rapid assessment of major trauma patients may shorten the time to diagnosis and the time for management.

A Meta Analysis of Using Structural Equation Model on the Korean MIS Research (국내 MIS 연구에서 구조방정식모형 활용에 관한 메타분석)

  • Kim, Jong-Ki;Jeon, Jin-Hwan
    • Asia pacific journal of information systems
    • /
    • 제19권4호
    • /
    • pp.47-75
    • /
    • 2009
  • Recently, researches on Management Information Systems (MIS) have laid out theoretical foundation and academic paradigms by introducing diverse theories, themes, and methodologies. Especially, academic paradigms of MIS encourage a user-friendly approach by developing the technologies from the users' perspectives, which reflects the existence of strong causal relationships between information systems and user's behavior. As in other areas in social science the use of structural equation modeling (SEM) has rapidly increased in recent years especially in the MIS area. The SEM technique is important because it provides powerful ways to address key IS research problems. It also has a unique ability to simultaneously examine a series of casual relationships while analyzing multiple independent and dependent variables all at the same time. In spite of providing many benefits to the MIS researchers, there are some potential pitfalls with the analytical technique. The research objective of this study is to provide some guidelines for an appropriate use of SEM based on the assessment of current practice of using SEM in the MIS research. This study focuses on several statistical issues related to the use of SEM in the MIS research. Selected articles are assessed in three parts through the meta analysis. The first part is related to the initial specification of theoretical model of interest. The second is about data screening prior to model estimation and testing. And the last part concerns estimation and testing of theoretical models based on empirical data. This study reviewed the use of SEM in 164 empirical research articles published in four major MIS journals in Korea (APJIS, ISR, JIS and JITAM) from 1991 to 2007. APJIS, ISR, JIS and JITAM accounted for 73, 17, 58, and 16 of the total number of applications, respectively. The number of published applications has been increased over time. LISREL was the most frequently used SEM software among MIS researchers (97 studies (59.15%)), followed by AMOS (45 studies (27.44%)). In the first part, regarding issues related to the initial specification of theoretical model of interest, all of the studies have used cross-sectional data. The studies that use cross-sectional data may be able to better explain their structural model as a set of relationships. Most of SEM studies, meanwhile, have employed. confirmatory-type analysis (146 articles (89%)). For the model specification issue about model formulation, 159 (96.9%) of the studies were the full structural equation model. For only 5 researches, SEM was used for the measurement model with a set of observed variables. The average sample size for all models was 365.41, with some models retaining a sample as small as 50 and as large as 500. The second part of the issue is related to data screening prior to model estimation and testing. Data screening is important for researchers particularly in defining how they deal with missing values. Overall, discussion of data screening was reported in 118 (71.95%) of the studies while there was no study discussing evidence of multivariate normality for the models. On the third part, issues related to the estimation and testing of theoretical models on empirical data, assessing model fit is one of most important issues because it provides adequate statistical power for research models. There were multiple fit indices used in the SEM applications. The test was reported in the most of studies (146 (89%)), whereas normed-test was reported less frequently (65 studies (39.64%)). It is important that normed- of 3 or lower is required for adequate model fit. The most popular model fit indices were GFI (109 (66.46%)), AGFI (84 (51.22%)), NFI (44 (47.56%)), RMR (42 (25.61%)), CFI (59 (35.98%)), RMSEA (62 (37.80)), and NNFI (48 (29.27%)). Regarding the test of construct validity, convergent validity has been examined in 109 studies (66.46%) and discriminant validity in 98 (59.76%). 81 studies (49.39%) have reported the average variance extracted (AVE). However, there was little discussion of direct (47 (28.66%)), indirect, and total effect in the SEM models. Based on these findings, we suggest general guidelines for the use of SEM and propose some recommendations on concerning issues of latent variables models, raw data, sample size, data screening, reporting parameter estimated, model fit statistics, multivariate normality, confirmatory factor analysis, reliabilities and the decomposition of effects.

A Comparative Study of Knowledge Integration in the Textbook and Students' Mental Model about the Phases of the Moon (달의 위상 변화에 관한 교과서의 지식 통합 과정 및 학생 정신 모델의 비교 연구)

  • Sung, Na-Hae;Choe, Seung-Urn
    • Journal of the Korean earth science society
    • /
    • 제29권2호
    • /
    • pp.163-174
    • /
    • 2008
  • In this study, we compared textbook knowledge organization with students' mental models to contribute to a more well-designed instruction scheme. The selected science content was the cause of moon phases. We investigated 9 textbooks and 25 third-year middle school students. Patterns and features in participants' mental models were identified through cross inter-rater data analysis by 9 researchers, including in service teachers and experts in science education. According to the results, observing and modeling are the main activities engaged in when dealing with moon phases. The activities consisted of such concepts as: lunar revolution, the sun's parallel rays, the illuminated half of moon, and the relative positions of the sun, moon, and earth. Each concept involved inquiry skills such as: creating and manipulating models, utilizing the relationship between time and space, and communicating. However, the most important skills which are required for authentic scientific inquiry, namely controlling variables and formulating hypotheses, were missing. We categorized students' mental models into three types: scientific models, mixed models, and alternative models. The knowledge structure of each of the models was also discussed in this paper. Consequently, it was found that, typically, students were not given enough opportunities to strengthen the connection among ideas.

The Relationship between the Oral Health Promotion Behavior and Dental Health Condition of Primary School Children (초등학생의 구강건강증진행위와 구강건강상태와의 관련성)

  • Kim, Soo-Kyung;Kim, Yoon-Sin
    • Journal of dental hygiene science
    • /
    • 제7권4호
    • /
    • pp.271-274
    • /
    • 2007
  • The purposes of this study were to understand the oral health promotion behavior and dental health condition of primary school children and to examine the relationships between the two variables. For that purpose, 729 fifth and sixth graders from four primary school located in Seoul were surveyed. In addition to the survey responses, dental examination results were used for analysis. The findings were as follows: 1. The children scored 3.51 out of full 5 points in oral health promotion behavior. they scored the highest at 3.82 in dietary habits, which were followed by going to a dentist for prevention purposes at 3.43, the method and frequency of brushing teeth at 3.40 and the use of fluorine at 3.39. 2. It turned out that 46.9% of the children had decayed permanent teeth. The number of decayed teeth was $1.66{\pm}2.32$, that of missing teeth was $0.03{\pm}0.24$. 3. There were reverse correlations(r = -0.32) between the children's subjective perception of their dental health condition and decayed teeth. The more positive perceptions they had for their own dental health condition, the less decayed teeth they had(p < 0.01). 4. There were also reverse correlations(r = -0.10) between the children's oral health promotion behavior and decayed teeth. The more they were engaged in Behavior of alimentation, the less decayed teeth they had(p < 0.01). The results indicate that primary school children can keep their dental health by practicing the right oral health promotion behavior, which calls for a need to develop and apply dental health education programs to promote the oral health promotion behavior among primary school children.

  • PDF