• Title/Summary/Keyword: Stratified sampling

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Analyses of the Efficiency in Hospital Management (병원 단위비용 결정요인에 관한 연구)

  • Ro, Kong-Kyun;Lee, Seon
    • Korea Journal of Hospital Management
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    • v.9 no.1
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    • pp.66-94
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    • 2004
  • The objective of this study is to examine how to maximize the efficiency of hospital management by minimizing the unit cost of hospital operation. For this purpose, this paper proposes to develop a model of the profit maximization based on the cost minimization dictum using the statistical tools of arriving at the maximum likelihood values. The preliminary survey data are collected from the annual statistics and their analyses published by Korea Health Industry Development Institute and Korean Hospital Association. The maximum likelihood value statistical analyses are conducted from the information on the cost (function) of each of 36 hospitals selected by the random stratified sampling method according to the size and location (urban or rural) of hospitals. We believe that, although the size of sample is relatively small, because of the sampling method used and the high response rate, the power of estimation of the results of the statistical analyses of the sample hospitals is acceptable. The conceptual framework of analyses is adopted from the various models of the determinants of hospital costs used by the previous studies. According to this framework, the study postulates that the unit cost of hospital operation is determined by the size, scope of service, technology (production function) as measured by capacity utilization, labor capital ratio and labor input-mix variables, and by exogeneous variables. The variables to represent the above cost determinants are selected by using the step-wise regression so that only the statistically significant variables may be utilized in analyzing how these variables impact on the hospital unit cost. The results of the analyses show that the models of hospital cost determinants adopted are well chosen. The various models analyzed have the (goodness of fit) overall determination (R2) which all turned out to be significant, regardless of the variables put in to represent the cost determinants. Specifically, the size and scope of service, no matter how it is measured, i. e., number of admissions per bed, number of ambulatory visits per bed, adjusted inpatient days and adjusted outpatients, have overall effects of reducing the hospital unit costs as measured by the cost per admission, per inpatient day, or office visit implying the existence of the economy of scale in the hospital operation. Thirdly, the technology used in operating a hospital has turned out to have its ramifications on the hospital unit cost similar to those postulated in the static theory of the firm. For example, the capacity utilization as represented by the inpatient days per employee tuned out to have statistically significant negative impacts on the unit cost of hospital operation, while payroll expenses per inpatient cost has a positive effect. The input-mix of hospital operation, as represented by the ratio of the number of doctor, nurse or medical staff per general employee, supports the known thesis that the specialized manpower costs more than the general employees. The labor/capital ratio as represented by the employees per 100 beds is shown to have a positive effect on the cost as expected. As for the exogeneous variable's impacts on the cost, when this variable is represented by the percent of urban 100 population at the location where the hospital is located, the regression analysis shows that the hospitals located in the urban area have a higher cost than those in the rural area. Finally, the case study of the sample hospitals offers a specific information to hospital administrators about how they share in terms of the cost they are incurring in comparison to other hospitals. For example, if his/her hospital is of small size and located in a city, he/she can compare the various costs of his/her hospital operation with those of other similar hospitals. Therefore, he/she may be able to find the reasons why the cost of his/her hospital operation has a higher or lower cost than other similar hospitals in what factors of the hospital cost determinants.

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Levels of Physicians' Self-assessment of Life Satisfaction and Associated Factors (임상의사의 삶의 만족도 자가평가 수준과 관련 요인)

  • Jong Sun Ok;Hyeongsu Kim
    • Journal of agricultural medicine and community health
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    • v.48 no.1
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    • pp.28-40
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    • 2023
  • Objectives: This study aimed to identify the level of self-assessment of life satisfaction and various factors related to the life satisfaction of Korean physicians. Methods: This study is a secondary data analysis using the 2016 Korean physician survey Korean Physician Survey(KPS) data collected by the Research Institute for Healthcare Policy of the Korean Medical Association. The member database(DB) of the Korean Medical Association was used for sampling and the target population was formed and surveyed by using stratified quota sampling. A questionnaire was sent by E-mail as an online survey method and was conducted for a total of 7 weeks from November 21, 2016 to January 8, 2017. The final number of respondents was 8,564 (response rate 13.8%). In this study, a total of 7,228 physicians, excluding residents and public health doctors who are currently treating patients directly, were studied. Factors affecting the life satisfaction of physicians were analyzed using ordinal logistic regression analysis. Results: The physical factors positively related to the life satisfaction of physicians were those who were in their 60s, female, and thought they had good health status. As for psychological factors, stress was low. As for economic factors, satisfaction with income was high. As for social factors, the physicians lived with their families and were satisfied with the time they could spend with them. Also, the physicians were satisfied with the social respect they received as a doctors. Conclusions: Based on the results of this study, it is thought that a multifaceted approach is needed to increase the life satisfaction of physicians.

Consumer Perceptions of Food-Related Hazards and Correlates of Degree of Concerns about Food (주부의 식품안전에 대한 인식과 안전성우려의 관련 요인)

  • Choe, Jeong-Sook;Chun, Hye-Kyung;Hwang, Dae-Yong;Nam, Hee-Jung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.1
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    • pp.66-74
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    • 2005
  • This survey was conducted to assess the consumer perceptions of food-related hazard in 500 housewives from all over Korea. The subjects were selected by stratified random sampling method. The survey was performed using structured questionnaire through telephone interview by skilled interviewers. The results showed that 34.6% of the respondents felt secure and were not concerned about food safety, and 65.4% were concerned about food safety. Logistic regression analysis showed that the increasing concern on food brands, food additives (such as food preservatives and artificial color), and imported foodstuffs indicated the current increasing concern on food safety. Other related factors indicating the increasing concern on food safety were education level and care for children's health. The respondents who cared about food safety expressed a high degree of concern on processed foodstuffs such as commercial boxed lunch (93.3%), imported foods (92.7%), fastfoods (89.9%), processed meat products (88.7%), dining out (85.6%), cannery and frozen foods (83.5%), and instant foods (82.0%). The lowest degree of concern was on rice. All the respondents perceived that residues of chemical substances such as pesticides and food additives, and endocrine disrupters were the most potential food risk factors, followed by food-borne pathogens, and GMOs (Genetically Modified Organisms). However, these results were not consistent with scientific judgment. Therefore, more education and information were needed for consumers' awareness of facts and myths about food safety. In addition, the results showed that consumers put lower trust in food products information such as food labels, cultivation methods (organic or not), quality labels, and the place of origin. Nevertheless, the respondents expressed their desire to overcome alienation, and recognized the importance of knowing of the origin or the producers of food. They identified that people who need to take extreme precautions on food contamination were the producers, government officials, food companies, consumers, the consumer's association, and marketers, arranged in the order of highest to lowest. They also believed that the production stage of agriculture was the most important step for improving the level of food safety Therefore, the results indicated that there is a need to introduce safety systems in the production of agricultural products, as follows: Good Agricultural Practice (GAP), Hazard Analysis and Critical Control Point (HACCP), and Traceability System (75).

Normal Predictive Values of Spirometry in Korean Population (한국인의 정상 폐활량 예측치)

  • Choi, Jung Keun;Paek, Domyung;Lee, Jeoung Oh
    • Tuberculosis and Respiratory Diseases
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    • v.58 no.3
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    • pp.230-242
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    • 2005
  • Background : Spirometry should be compared with the normal predictive values obtained from the same population using the same procedures, because different ethnicity and different procedures are known to influence the spirometry results. This study was performed to obtain the normal predictive values of the Forced Vital Capacity(FVC), Forced Expiratory Volume in 1 Second($FEV_1$), Forced Expiratory Volume in 6 Seconds($FEV_6$), and $FEV_1/FVC$ for a representative Korean population. Methods : Based on the 2000 Population Census of the National Statistical Office of Korea, stratified random sampling was carried out to obtain representative samples of the Korean population. This study was performed as a part of the National Health and Nutrition Survey of Korea in 2001. The lung function was measured using the standardized methods and protocols recommended by the American Thoracic Society. Among those 4,816 subjects who had performed spirometry performed, there was a total of 1,212 nonsmokers (206 males and 1,006 females) with no significant history of respiratory diseases and symptoms, with clear chest X-rays, and with no significant exposure to respiratory hazards subjects. Their residence and age distribution was representative of the whole nation. Mixed effect models were examined based on the Akaike's information criteria in statistical analysis, and those variables common to both genders were analyzed by regression analysis to obtain the final equations. Results : The variables affecting the normal predicted values of the FVC and $FEV_6$ for males and females were $age^2$, height, and weight. The variables affecting the normal predicted values of the $FEV_1$ for males and females were $age^2$, and height. The variables affecting the normal predicted values of the $FEV_1/FVC$ for male and female were age and height. Conclusion : The predicted values of the FVC and $FEV_1$ was higher in this study than in other Korean or foreign studies, even though the difference was < 10%. When compared with those predicted values for Caucasian populations, the study results were actually comparable or higher, which might be due to the stricter criteria of the normal population and the systemic quality controls applied to the whole study procedures together with the rapid physical growth of the younger generations in Korea.

A Study on the Relationship between Adolescent Misconducts and Harmful Environment Based on Health Belief Model (건강신념모델을 적용한 청소년 비행과 유해환경과의 관련성 연구)

  • 이명선
    • Korean Journal of Health Education and Promotion
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    • v.18 no.3
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    • pp.37-58
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    • 2001
  • This study placed its objectives in suggesting the basic data for setting up an approach to protect the educational environment, by analyzing the relevance between the misconducts of adolescence and the harmful environment around the school, as an object of study, middle school students and high school students all over the country. Thus, this study carried out the questionnaire survey, by the multi-stage of stratified sampling in 2,114 middle school and high school students from June 29, 2000 through July 29, 2000. And the results of analysis were as follows: 1. In case of the ratio of students using harmful environment, the electronic game room had the highest ratio (78.3%); next, the PC room (75.6%), the singing room (71.6%), and the cartoon room (34.3%). 2. In terms of the experiences of using the harmful environment according to the personal characteristics, high school students used it in a higher ratio, compared with middle school students (p〈0.001); the students, whose father graduated from a high school, comparatively used it much more(p〈0.05). Also, when a school is located near to amusement quarters or shopping centers, students used the harmful environment most highly (p〈0.001). And the differences were found to be statistically significant. 3. In case of the perceived susceptibility factors, the harmful environment was found to be used in lower ratio, by the students who answered “very so” to the question item, The more harmful environment facilities are positioned around school, the more student have the opportunities to use them. (p〈0.001). That is, the findings showed that the higher students' degree of perceived susceptibility factors was the less students used harmful environment facilities. The differences were statistically significant. In terms of the ratio of using harmful environment according to perceived seriousness factors, it was founded out that the students, who answered, “If I use any harmful environment facilities, it will be very harmful to myself.”. had the less opportunities of having used them, compared with the students who did not answer so (p〈0.001). This indicated that the higher the degrees perceived seriousness of students, the less they used harmful environment facilities. And the differences were statistically significant. In the side of the ratio of using harmful environment according to the perceived barriers, it was found out that there were any special large differences. That is, perceived barriers had nothing to do with students' using harmful environment. 4. As the result of having analyzed the factors influencing the behaviors of using harmful environment, the factor to explain the behaviors of using harmful environment was found to be the degree of perceived seriousness, among individual perceiving factors; next, the location of a school - one of personal characteristics, the degree of perceived susceptibility and ages, m sequence. 5. Among students' misconduct experiences, drinking was highest (21.6%), next, smoking (11.9%), drug abuse (4.3%), and sexual relations (1.6%), In sequence. Among other problematic behaviors, excessive waste was highest (14.6%); next, disobedience and lie (10.7%), night wandering (7.8%), and bad dressing and making-up (5.5%), in sequence. 6. In terms of the misconducts according to the behaviors of using harmful environment, compared with the students who did not commit any misconducts, harmful environment facilities were used more highly, by each group of students who experienced drinking (p〈0.00l), smoking (p〈0.001), sexual relations (p〈0.05), excessive waste (p〈0.001), disobedience & lie (p〈0.001), and bad dressing & making-up (p〈0.05). And the differences were statistically significant.

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Attitude of Hospital Staff toward Hospice Care - The Program at Wonju Christian Hospital - (일 병원직원들의 호스피스 프로그램에 대한 인식)

  • Choi, Sang-Soon;Hu, Hea-Kung;Park, So-Mi;Kim, Dae-Ran;Kim, Ki-Kyong;Rhoe, Byoung-Seon
    • Journal of Hospice and Palliative Care
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    • v.4 no.2
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    • pp.145-153
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    • 2001
  • Purpose : This study was conducted to describe the attitude of hospital staff toward the hospice program. The purpose of this study was to promote the extension and organization of hospice activities to include hospital staff. Method : This is a descriptive study using a survey method. The subjects for this study were the nurses, physicians, technicians, and support staff at Wonju Christian Hospital. Using a stratified sampling method based on position of staff, the researchers recruited 430 staff members as the sample for this study. Data collection was done through a questionnaire developed by the researchers. The data were analyzed using descriptive statistics and content analysis. Findings : 1)Ninety seven percent (n=417) of the subjects understood the concept of hospice care, and 97.4% (n=419) answered that dying patients should be respected. When considering the hospice team, the subjects of this study indicated that the team should include family members (n=245), physicians (n=77), pastors (n=41), and nurses (n=34), in that order of priority. 2) When asked to indicate priorities for systematic operation of a hospice program, the subjects indicated that the highest priority was "setting up a team for hospice service(31.4%)", followed by "setting up a hospice ward(28.6%)". Sixty seven percent(n=289) recognized the importance of the hospice activities provided by the volunteers, and 85.3%(n=367) intended to use the hospice service of the hospital. The highest merit of hospital-based hospice program is 'acomplishment of mission'. 3) The average score on attitude toward death was 2.84(maximum=4), and the best needful service except hospitalization is 'constructing of support system'. Conclusion : Most of the staff at Wonju Christian Hospital perceive the necessity for systematic hospice activities, and that to achieve this goal, administrative and structural support at the hospital governance level is the first necessity. The results of this study could be useful for any hospital which is in the first stages of setting up and promoting a hospice program.

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Manufacturing Location and Linkages in the Suburb of Metropolitan Pusan (부산시 근교의 공업입지와 지역적 연계)

  • Lim, Yeong-Dae
    • Journal of the Korean association of regional geographers
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    • v.6 no.1
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    • pp.1-28
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    • 2000
  • The purpose of this study is to clarify the suburbanization of manufacturing, and location and linkages of decentralized manufacturing from Metropolitan Pusan by means of case study on manufacturing location and linkages in the suburb of Metropolitan Pusan. Kimhae city and Yangsan-Gun toward which heavy decentralization of manufacturing from the Metropolitan Pusan has been done. Both hard data and soft data were used as the basic data. Hard data are the statistical data in statistical yearbooks and firm list in directories. The former consists of the number of establishments and employees classified by product type, firm size and unit area. The latter consists of owner's names, addresses, employee number, products and headquarters of firms. Soft data are the results of the interviews with the 242 owners of firms in the four case study areas selected by Proportional Stratified Sampling Method. The major findings are as follows: 1. The spatial variations of manufacturing in the suburb was regularized in the latter half of 1970's. The primary processes to decentralize manufacturing from Metropolitan Pusan were the birth, relocation and establishment of branches of the firms. Among them the relocation of small outer-oriented single-location firms from Pusan was the most important. 2. The spatial variations undergoing spatial expansion of manufacturing distribution and increase of agglomeration degree of manufacturing, proceeded from the adjacents of Metropolitan Pusan to the outer areas along the main transportation route. 3. The main factors which caused manufacturing to decentralize from the Metropolitan Pusan were firm policy and land for this policy. The main locational factors which induced the decentralizing manufacturing into the suburb were land, market and transportation. 4. The strength of linkages with the outside of the study area is stronger than that of linkages with the inside. There is distance-decay-function in the strength of linkages with the outside, and linkages with short distant areas are stronger than those with long distant areas. 5. The ranges of spatial linkages in procurement of materials, in subcontraction and in marketing are wider than those in ordering. 6. The main factors which cause the formation of linkages are different by types of linkages: monopolistic and oligopolistic supply are important in procurement linkages; characteristics of products and the subsequent marketing difficulties, in subcontraction linkages; fluctuation, cost reduction, insufficient facility and characteristics of products, in ordering linkages; subcontract, characteristics of product and the subsequent marketing difficulties, in marketing linkages. 7. The changes of linkages owing to locational changes of firms were great, and were greater in long distant areas than in short distant areas. 8. The main factor influencing on the changes of linkages was the easiness in the transportation of goods, movement of labour and contacts with customers. In conclusion, some facts described above were proved to be consistent with the results of proceeding studies in the other areas: influence of relocation of decentralizing firms on the suburbanization; the factors of manufacturing decentralization; spatial characteristics of linkages; linkage changes owing to relocation of firms. Some were proved to be partly consistent: locational factors inducing decentralized manufacturing into the suburb were proved to be inconsistent. I think that the results of previous studies on the other areas can be applicable to the explanation on the decentralization of Metropolitan manufacturing from the viewpoint of the suburb. For the better explanation on the decentralization of Metropolitan manufacturing, more empirical case studies on the suburbanization of manufacturing are necessary.

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The Relationship Between Social Security Network and Security Life Satisfaction in Community Residents: Scale Development and Application of Social Security Network (사회안전망과 지역사회주민의 안전생활만족의 관계: 사회안전망 척도개발과 적용)

  • Kim, Chan-Sun
    • The Journal of the Korea Contents Association
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    • v.14 no.6
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    • pp.108-118
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    • 2014
  • The purpose of this study is to develop a relationship of measuring method for the social security network and verify its validity and reliability and apply it to investigate the due to security life satisfaction. This study is based by setting general residents of Seoul in 2013 and using the stratified cluster random sampling method to analyze a total amount of 203 examples. The measuring methods for the social security network was developed through document research, conceptual definition and drafting the survey, experts' conference, preliminary inspection and original examination, verification of the validity and reliability of the survey. An experts' conference took pace to verify the validity of the survey, and 6 factors were extracted through exploratory factor analysis crime prevention design, street CCTV facilities, volunteer neighborhood patrol, local government security education, police public peace service, private security service. The conclusion are the following. Collected data was analyzed based on the aim of this study using SPSSWIN 18.0, and practice frequency analysis, F test, factor analysis, reliability analysis, correlation analysis, multiple regression analysis. First, the validity of the social security network measurement is very high. Thus, the factors constituting the social security network were found to be crime prevention design, street CCTV facilities, volunteer neighborhood patrol, local government security education, police public peace services, and private security services, and the crime prevention design factor was found to be most explanatory. Second, the reliability of the social security network measurement is very high. Thus, the correlation between the questions and the sector, the questions and the social security net was very high, and the internal consistency showed a Cronbach's${\alpha}$ value of over 0.865. Third, the establishment of a social security network had the biggest effect on people in their forties. Thus, when the crime prevention design, street CCTV facilities, local government security education, police public peace services are systematically established, the social anxiety of citizens was reduced.

Exploratory Case Study for Key Successful Factors of Producy Service System (Product-Service System(PSS) 성공과 실패요인에 관한 탐색적 사례 연구)

  • Park, A-Rum;Jin, Dong-Su;Lee, Kyoung-Jun
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.255-277
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    • 2011
  • Product Service System(PSS), which is an integrated combination of product and service, provides new value to customer and makes companies sustainable as well. The objective of this paper draws Critical Successful Factors(CSF) of PSS through multiple case study. First, we review various concepts and types in PSS and Platform business literature currently available on this topic. Second, after investigating various cases with the characteristics of PSS and platform business, we select four cases of 'iPod of Apple', 'Kindle of Amazon', 'Zune of Microsoft', and 'e-book reader of Sony'. Then, the four cases are categorized as successful and failed cases according to criteria of case selection and PSS classification. We consider two methodologies for the case selection, i.e., 'Strategies for the Selection of Samples and Cases' proposed by Bent(2006) and the seven case selection procedures proposed by Jason and John(2008). For case selection, 'Stratified sample and Paradigmatic cases' is adopted as one of several options for sampling. Then, we use the seven case selection procedures such as 'typical', 'diverse', 'extreme', 'deviant', 'influential', 'most-similar', and 'mostdifferent' and among them only three procedures of 'diverse', 'most?similar', and 'most-different' are applied for the case selection. For PSS classification, the eight PSS types, suggested by Tukker(2004), of 'product related', 'advice and consulancy', 'product lease', 'product renting/sharing', 'product pooling', 'activity management', 'pay per service unit', 'functional result' are utilized. We categorize the four selected cases as a product oriented group because the cases not only sell a product, but also offer service needed during the use phase of the product. Then, we analyze the four cases by using cross-case pattern that Eisenhardt(1991) suggested. Eisenhardt(1991) argued that three processes are required for avoiding reaching premature or even false conclusion. The fist step includes selecting categories of dimensions and finding within-group similarities coupled with intergroup difference. In the second process, pairs of cases are selected and listed. The second step forces researchers to find the subtle similarities and differences between cases. The third process is to divide the data by data source. The result of cross-case pattern indicates that the similarities of iPod and Kindle as successful cases are convenient user interface, successful plarform strategy, and rich contents. The differences between the successful cases are that, wheares iPod has been recognized as the culture code, Kindle has implemented a low price as its main strategy. Meanwhile, the similarities of Zune and PRS series as failed cases are lack of sufficient applications and contents. The differences between the failed cases are that, wheares Zune adopted an undifferentiated strategy, PRS series conducted high-price strategy. From the analysis of the cases, we generate three hypotheses. The first hypothesis assumes that a successful PSS system requires convenient user interface. The second hypothesis assumes that a successful PSS system requires a reciprocal(win/win) business model. The third hypothesis assumes that a successful PSS system requires sufficient quantities of applications and contents. To verify the hypotheses, we uses the cross-matching (or pattern matching) methodology. The methodology matches three key words (user interface, reciprocal business model, contents) of the hypotheses to the previous papers related to PSS, digital contents, and Information System (IS). Finally, this paper suggests the three implications from analyzed results. A successful PSS system needs to provide differentiated value for customers such as convenient user interface, e.g., the simple design of iTunes (iPod) and the provision of connection to Kindle Store without any charge. A successful PSS system also requires a mutually benefitable business model as Apple and Amazon implement a policy that provides a reasonable proft sharing for third party. A successful PSS system requires sufficient quantities of applications and contents.

DEVELOPMENT OF SCALE FOR MEASURING DELINQUENT BEHAVIOR (청소년 비행행동 측정도구 개발)

  • Kim, Hyun-Sil;Kim, Hun-Soo
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.11 no.1
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    • pp.79-90
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    • 2000
  • Objective:This study was performed in order to develop a measuring instrument for assessing and predicting delinquent behavior of the adolescents in Korea. Methods:This study was methodological research for developing a questionnaire for measuring delinquent behavior. Through the relevant literature review and personal interview using open-ended question with 12 adolescents in schools, outpatient basis and the juvenile corrective institutions, the author developed a pre-questionnaire with 31 items for assessing delinquent behavior among delinquentprone adolescents. Statistical method employed were test-retest reliability and Cronbach's alpha coefficient for testing reliability and factor analysis for testing validity of this questionnaire, and t-test for mean difference between student adolescents and delinquent adolescents, using SAS program. Subject served for this study consisted of 2,177 adolescents including 1,206 students and 971 delinquent adolescents by proportional stratified random sampling method. Results:1) Three stable factors were emerged and these contributed 52.2% of the variance in the total score. All 31 items loaded above .40 on each factor. 2) Factor I was named as antisocial delinquent behavior(17 items), factor II was named as aggressive delinquent behavior(8 items), and factor III was named as psychopathic delinquent behavior(6 items). 3) Comparison of these 3 factors between student adolescents and delinquent adolescents showed that there was a significant difference in factor Ⅰ(t=-42.91(student), -41.71(delinquent), p=.0001), factor II(t=-34.10(student), -35.72(delinquent), p=.0001), factor III(t=-14.24(student), -14.26 (delinquent), p=.0000), and total score(t=37.02(student), -36.38(delinquent), p=.0001). 4) Internal consistency reliability was tested by Cronbach's ${\alpha}$. Cronbach's ${\alpha}$ was .952 for total 31 items and .950, .866 and .721 for each 3 factors related to delinquent behavior. Conclusions:The author confirmed that this scale can use for measuring delinquent behavior, and hope to make a contribution to screening test and prevention of juvenile delinquency in Korea.

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