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The Effect of Technology-Based Entrepreneurship(TBE) Activities on Firms Growth (기술기반창업기업의 기업활동이 기업성장에 미치는 영향)

  • Lee, Myung-Jong;Joo, Youngjn
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.14 no.6
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    • pp.59-76
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    • 2019
  • Most technology-based entrepreneurship(TBE) go through an process of decline or disappear without overcoming the valley of death(VoD). The purpose of this study is to identify the growth dimension of TBE and to test the influence of firms activities on firms growth over time. This study identified the two-dimensional growth dimension divided by size and profit through exploratory factor analysis(EFA) of a number of growth indicators. Then, we defined the discrete state of growth firm in four states, divided by size and profit, and five states, including the closure of business. Multi-nomial logit model is used to predict the effect of TBE activities on a discrete state of growth firm(size×profit, closure of business) based on multiple independent variables. The independent variables are based on five representative firms activities: employment, marketing, R&D, financial activities, and general management activities. The growth stage of TBE over time has been categorized into three stages: early stage, middle stage, and late stage of business, taking into account the main periods during which the survival rate of startups sharply decreases. The analytical data of this study was based on the secondary data of the start-up supporting companies of government and public institutions. The subjects of analysis were TBE within 10 years. As a result of the empirical analysis, the employment and marketing activities of TBE show that early and mid-term activities had an effect on the state of firms growth. However, if there is a difference, employment activities have both positive and negative effects, while marketing activities have only a positive effect on size and profit growth. And besides, R&D activities, financial activities, and general management activities throughout the entire process of firms growth were found to be firms activities that have both positive and negative effects on firms growth. In addition, the age of the founder, the firms' industry, and the geographic location of the firms, which are general characteristics of the company, were found to have a distinctive effect on the growth status of the firms according to the growth stage.

Suitability Assessment of Domestic Natural Waters as a Culture Medium for Daphnia magna (Daphnia magna의 배양배지로서 국내 자연수의 적절성 평가)

  • Yeom, Dong-Hyuk;Jeon, Chan-Sig
    • Korean Journal of Ecology and Environment
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    • v.45 no.3
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    • pp.271-277
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    • 2012
  • The present study was conducted to assess the suitability of domestic natural waters as a Daphnia magna culture medium. In order to assess survival rate and reproductive output, young female daphnids (parent animals), aged less than 24 hours at the start of the test and produced in the Elendt M4 medium, were exposed to Elendt M4 medium, de-chlorinated tap water, and natural mineral water for 21 days. D. magna cultured in Elendt M4 medium (reference medium) and natural mineral water met the criteria of OECD No. 211, Daphnia magna Reproduction Test Guidelines in terms of percent adult survival, first day of reproduction, and average young production. However, the mortalities of adult daphnids observed in de-chlorinated tap water were more than 20% in two reproduction tests for 21 days. Mortality was observed on exposure days 13, 15, and 18 in de-chlorinated water. The use of D. magna is recommended in water of hardness >80 mg $CaCO_3\;L^{-1}$. However, the hardness of de-chlorinated tap water used in the present study was 50~53 mg $CaCO_3\;L^{-1}$. Therefore, it is judged that the delayed mortalities observed in de-chlorinated tap water were caused by a rapid decreased in hardness when the medium was changed from Elendt M4 to de-chlorinated tap water. When D. magna is cultured using domestic natural waters (underground water, surface water, and de-chlorinated water), the quality-control (QC) data should be maintained through a standardization for health assessment method, toxicity test method using reference chemical, test intervals of reference toxicant toxicity test, and data treatment and interpretation. In the long term, national research programs are needed for the development of test species which are representative of domestic aquatic environmental conditions among indigenous daphnids.

Early Clinical Experience in Valve Replacement Using On-X Prosthetic Heart Valve (On-X 기계판막을 이용한 판막치환술의 단기성적분석)

  • 김인섭;김우식;신용철;유환국;김병열;정성철
    • Journal of Chest Surgery
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    • v.37 no.9
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    • pp.742-748
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    • 2004
  • The On-X valve was recently introduced. It was the aim of this study to assess the safety and feasibility from the data derived from 28 patients who underwent aortic and/or mitral valve replacement with this prosthesis in National Medical Center. Material and Method: From May 1999 and May 2003, a series of 28 consecutive patients who had been implanted with 32 On-X prosthesis were reviewed, The operative procedure comprised of 12 MVR, 10 AVR and 6 DVR. The study followed the guidelines of AATS/STS. Mean follow-up was 27 months (total 04 patient-years). Result: Early ($\leq$30 days) mortality was 7.44% (2/28) and no late mortality occurred in the study. Total actuarial freedom from mortality at 2 years was 92.86$\pm$4.87% for all cases, 100% for MVR, 90$\pm$9.49% for AVR, and 83.3$\pm$1.52% for DVR. Thromboembolic event occurred in 2 MVR patients and that was the only complication; therefore, the linearized incidence of valve related complications was 3.17%/ patient-years for all cases and 6.5%/patient-years for MVR and the actuarial freedom from valve related complications at 2 years was 84.85$\pm$10.75%. Preoperatively, 24 (85.71%) patients were in NYHA functional class III or IV but postoperatively, 25 (89,29%) patients were in NYHA functional class I or II. The levels of hemoglobin, hematocrit, serum LDH, reticulocyte rate and indirect bilirubin were all within normal range at postoperative 3 month. In mitral position, the peak gradient was 6.1$\pm$1.8 mmHg and the mean gradient was 3.0$\pm$0.6 mmHg and EOA were 2.54$\pm$0.56 $m^2$, 2.39$\pm$0.73 $m^2$, 2.34$\pm$0.55 $m^2$, 2.40$\pm$0.63 $m^2$ at 27 mm, 29 mm, 31 mm, 33 mm respectively. In aortic postion, the peak gradient was 21.1 $\pm$14.12 mmHg and the mean gradient was 12.3$\pm$6.52 mmHg. Conclusion: Since there was no significant difference in the postoperative mortality, valve related complications and echocardiographic hemodynamic data compared to standard bileaflet design and since there was an improvement in the NYHA functional class and normal values of hemolytic indicators, it can be assumed that On-X valve is safe and feasible. However, accumulation of cases and long-term follow-up of this patient group is needed to establish this result.

Effects of Strength Recognition on the Intent of Start-up after Retirement: To the Office Workers (강점인식이 은퇴 후 창업의도에 미치는 영향: 직장인을 대상으로)

  • Park, Hye sung;Park, Woojin;Yun, Bae byung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.1
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    • pp.143-150
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    • 2020
  • This research is intended to identify how office worker's recognition of strength affects the intention of starting a business when it is used as a medium for utilizing strength. The survey period was conducted for two months from January 17, 2019 to March 8, 2019. In order to achieve the object of this study, a significant number of employees have been collected nationwide, and 287 office workers were analyzed after collecting 300 questionaires, excluding 13 office workers who were not sincere. The significant data were analyzed by utilizing the structural equation and technical statistics and by verifying the conformity of structural model and measurement model and by investigating the relationship between variables. The results of this study are summarized as follows: First, employee's perception of strength has been found to have a significant effect on the utilizing of strength. Second, the use of workers' strengths has been found to have a significant effect on the intention of starting a business. Third, it has been confirmed that in the relationship between the employee's perception of strength and intention to start a business, the recognition of strength has a significant effect on the intention of starting a business only through the use of strength. Most office workers are nervous about the future and make various plans. The time to live after retirement is getting longer and jobs and working hours are shrinking at an alarming rate. According to the analysis on the status of small business owners in the mid-term of 2017 data, the average monthly operating profit of small business owners across the country is decreasing over the years, and most start-ups are subsistence-type start-ups, and they decide to start their own businesses because they have no other choice than start-ups. As the number of small business owners suffering from financial difficulties has increased since the financial crisis and insecurity of job is pushing those with financial difficulties after retirement to the battleground of the start-up market, the result of this research suggest that the workers need to recognize their own strength and enhance the importance of utilizing the strength.

Comprehensive Geriatric Assessment for Community Living Elderly in a Rural Area (일부 농촌지역 거주 노인들에 대한 포괄적 노인평가)

  • Rhee, Jung-Ae;Shin, Hee-Young;Chung, Eun-Kyung;Shin, Jun-Ho
    • Journal of agricultural medicine and community health
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    • v.27 no.1
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    • pp.21-31
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    • 2002
  • The aim of this study was to analyse and conduct the comprehensive geriatric assessment for the elderly in rural area. The subjects were 388 older people aged 65 years or older living in the community. Data for comprehensive assessment such as physical, mental, functional, social and environmental conditions were collected from January to February, 2001 through a person-to-person interview. Of the total 388 olders, 169(43.6%) were men and 219(56.4%) were women. Mean ages of men and women were $73.5{\pm}6.4$ and $74.0{\pm}6.2$ years respectively. Three common diseases of the elderly were arthralgia(51.6%), chronic back pain(33.2%) and hypertension(18.6%), and higher in women than in men. Impairment rate of vision, hearing and bowel or bladder control was 59.0%, 20.1%, and 28.4% respectively. But that of lover extremities 3.4%. In terms of cognitive function, short term memory loss was found in 33.7% of males and 44.7% of females. The percentage of fully independent in the six ADL items was 72.2% in men and 58.9% in women. In the social supportive system, 49.5% of the elderly were living with spouse, and 22.9% living alone, 26.3% having care giver. These results will provide basic data for the development of community-based health program, which gives appropriate health service for the elderly living in the community.

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Measurements of Actual Effective Half-Life in $^{131}I$ Therapy for Graves' Hyperthyroidism (그레이브스 갑상선기능항진증 환자의 방사성옥소($^{131}I$) 치료시 실제 유효반감기의 측정)

  • So, Yong-Seon;Kim, Myung-Seon;Kwon, Ki-Hyun;Kim, Seok-Whan;Kim, Tae-Hyung;Han, Sang-Woong;Kim, Eun-Sil;Kim, Chong-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.30 no.1
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    • pp.77-85
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    • 1996
  • Radioiodine($^{131}I$) has been used for the treatment of Graves' hyperthyroidism since the late 1940's and is now generally regarded as the treatment of choice for Graves' hyperthyroidism who does not remit following a course of antithyroid drugs. But for the dose given, several different protocols have been described by different centers, each attempting to reduce the incidence of long-term hypothyroidism while maintaining an acceptable rate control of Graves' hyperthyroidism. Our goals were to evaluate effective half-life and predict absorbed dose in Graves' hyperthyroidism patients, therefore, to calculate and readminister radioiodine activity needed to achieve aimed radiation dose. Our data showed that the mean effective $^{131}I$ half-life for Graves' disease is 5.3 days(S.D=0.88) and mean biologic half-life is 21 days, range 9.5-67.2 days. The mean admininistered activity and the mean values of absorbed doses were 532 MBq(S.D.=254), 112 Gy (S.D.=50.9), respectively. The mean activity needed to achieve aimed radiation dose were 51MBq and marked differences of $^{131}I$ thyroidal uptake between tracer and therapy ocurred in our study. We are sure that the dose calculation method that uses 5 days thyroidal $^{131}I$ uptake measurements after tracer and therapy dose, provides sufficient data about the effective half-life and absorbed dose of $^{131}I$ in the thyroid and predict the effectiveness of $^{131}I$ treatment in Graves' hyperthyroidism.

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A longitudinal analysis of high school students' dropping out: Focusing on the change pattern of dropout, changes in school violence and school counseling. (전국 고등학교 학생의 학업중단에 대한 종단적 분석 -학업중단 변화양상에 따른 유형탐색, 학교폭력 및 학교상담의 변화추이를 중심으로-)

  • Kwon, Jae-Ki;Na, Woo-Yeol
    • Journal of the Korean Society of Child Welfare
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    • no.59
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    • pp.209-234
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    • 2017
  • This study viewed schools as a cause of students dropping out and posited that dropping out of high school would vary depending on the characteristics and influencing factors of the school from which students were dropping out. Therefore, focusing on schools, we longitudinally investigated the change patterns of school dropout across high schools in the country, and the types of changes in dropping out of high school. In addition, we predicted the general characteristics of schools according to the type of school students were dropping out from, looked at the changes in the major factors (i.e., school violence and school counseling) affecting school dropout, and reviewed schools' long-term efforts and outcomes in relation to school dropout. For this purpose, KERIS EDSS's "Secondary School Information Disclosure Data" were used. The final model included data collected five years20122016) from high schools across the country. The results were as follows. First, in order to examine the longitudinal change patterns of dropping out of high schools, a latent growth models analysis was conducted, and it revealed that, as time passed, the dropout rate decreased. Second, growth mixture modeling was used to explore types according to the change patterns of the school students were dropping out from. The results showed three types: the "remaining in school" type, the "gradually decreasing school dropout" type, and the "increasing school dropping out". Third, the multinomial logistic regression was conducted to predict the general characteristics of schools by type. The results showed that public schools, vocational schools, and schools with a large number of students who have below the basic levels in Korean, English and mathematics were more likely to belong to the "increasing school dropout" type. Further, the larger the total number of students, the higher the probability of belonging to the "remaining in school" type or the "gradually decreasing school dropout" type. Lastly, growth mixture modeling was used to analyze the trend of school violence and school counseling according to the three types. The focus was on the "gradually decreasing school dropout" type. In the case of the "gradually decreasing school dropout" type, it was found that as time passed, the number of school violence cases and the number of offenders gradually decreased. In addition, in terms of change in school counseling the results revealed that the number of placement of professional counselors in schools increased every year and peer counseling was continuously promoted, which may account for the "gradually decreasing school dropout" type.

Clinical Results and Optimal Timing of OPCAB in Patients with Acute Myocardial Infarction (급성 심근경색증 환자에서 시행한 OPCAB의 수술시기와 검색의 정도에 따른 임상성적)

  • Youn Young-Nam;Yang Hong-Suk;Shim Yeon-Hee;Yoo Kyung-Jong
    • Journal of Chest Surgery
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    • v.39 no.7 s.264
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    • pp.534-543
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    • 2006
  • Background: There are a lot of debates regarding the optimal timing of operation of acute myocardial infarction (AMI). Off pump coronary artery bypass grafting (OPCAB) has benefits by avoiding the adverse effects of the cardio-pulmonary bypass, but its efficacy in AMI has not been confirmed yet. The purpose of this study is to evaluate retrospectively early and mid-term results of OPCAB in patients with AMI according to transmurality and timing of operation. Material and Method: Data were collected in 126 AMI patients who underwent OPCAB between January 2002 and July 2005, Mean age of patients were 61.2 years. Male was 92 (73.0%) and female was 34 (27.2%). 106 patients (85.7%) had 3 vessel coronary artery disease or left main disease. Urgent or emergent operations were performed in 25 patients (19.8%). 72 patients (57.1%) had non-transmural myocardial infarction (group 1) and 52 patients (42.9%) had transmural myocardial infarction (group 2). The incidence of cardiogenic shock and insertion of intra-aortic balloon pump (IABP) was higher in group 2. The time between occurrence of AMI and operation was divided in 4 subgroups (<1 day, $1{\sim}3\;days,\;4{\sim}7\;days$, >8 days). OPCAB was performed a mean of $5.3{\pm}7.1$ days after AMI in total, which was $4.2{\pm}5.9$ days in group 1, and $6,6{\pm}8.3$ days in group 2. Result: Mean distal an-astomoses were 3.21 and postoperative IABP was inserted in 3 patients. There was 1 perioperative death in group 1 due to low cardiac output syndrome, but no perioperative new MI occurred in this study. There was no difference in postoperative major complication between two groups and according to the timing of operation. Mean follow-up time was 21.3 months ($4{\sim}42$ months). The 42 months actuarial survival rate was $94.9{\pm}2.4%$, which was $91.4{\pm}4.7%$ in group 1 and $98.0{\pm}2.0%$ in group 2 (p=0.26). The 42 months freedom rate from cardiac death was $97.6{\pm}1.4%$ which was $97.0{\pm}2.0%$ in group 1 and $98.0{\pm}2.0%$ in group 2 (p=0.74). The 42 months freedom rate from cardiac event was $95.4{\pm}2.0%$ which was $94.8{\pm}2.9%$ in group 1 and $95.9{\pm}2.9%$ in group 2 (p=0.89). Conclusion: OPCAB in AMI not only reduces morbidity but also favors hospital outcomes irrespective of timing of operation. The transmurality of myocardial infarction did not affect the surgical and midterm outcomes of OPCAB. Therefore, there may be no need to delay the surgical off-pump revascularization of the patients with AMI if surgical revascularization is indicated.

The Determination of Trust in Franchisor-Franchisee Relationships in China (중국 프랜차이즈 시스템에서의 본부와 가맹점간 신뢰의 영향요인)

  • Shin, Geon-Cheol;Ma, Yaokun
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.2
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    • pp.65-88
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    • 2008
  • Since the implementation of economic reforms in 1978, the Chinese economy grows rapidly at an average annul growth rate of 9% over the post two decades. Franchising has been widely recognized as an important source of entrepreneurial activity. Trust is important in that it facilitates relational exchanges by permits partners to transcend short-run inequities or risks to concentrate on long-term profits or gains. In the relationship between the franchisors and franchisees, trust has been described as an important source of competitive advantage. However, little research has been done on the factors affecting trust in Chinese franchisor-franchisee relationships. The purpose of this study is to investigate what factors affect the trust in the franchise system in China, and to provide guidelines and insights to franchisors which enter Chinese market. In this study, according to Morgan and Hunt (1994), trust is defined as the extending when one party has confidence in an exchange partner's reliability and integrity. We offered a conceptual model of the empirical study. The model shows that the factors affecting the trust include franchisor's supports, communication, satisfaction with previous outcome and conflict. We also suggested the franchisor's supports and communication like to enhance the franchisee's satisfaction with previous outcome, and the franchisor's supports, communication and he franchisee's satisfaction with previous outcome tend to decrease conflict. Before the formal study, a pretest involving exploratory interviews with owners from three franchisees was conducted to make sure the questionnaire was relevant and clear to the respondents. The data were collected using trained interviewers to carry out personal interviews with the aid of an unidentified, muti-page, structured questionnaire. The respondents comprised of owners, managers, and owner managers of franchisee-owned food service franchises located in Beijing, China. Even though a total of 256 potential franchises were initially contacted, the finally usable sample consisted of 125 respondents. As expected, the sampling method was successful in soliciting respondents with waried personal and firm characteristics. Self-administrated questionnaires were used for all measures. And established scales were used to measure the latent constructs in this study. The measures tapped the franchisees' perceptions of the relationship with the referent franchisor. Five-point Likert-type scales ranging from "strongly disagree" (=1) to "strongly agree" (=7) were used throughout the constructs (trust, eight items; support, five items; communication, four items; satisfaction, six items; conflict, three items). The reliability measurements traditionally employed, such as the Cronbach's alpha, were used. All the reliabilities were greater than.80. The proposed measurement model was estimated using SPSS 12.0 and AMOS 5.0 analysis package. We conducted A series of exploratory factor analyses and confirmatory factor analyses to assess the convergent validity, discriminant validity, and reliability. The results indicate reasonable overall fits between the model and the observed data. The overall fit of measurement model were $X^2$= 159.699, p=0.004, d.f. = 116, GFI =.879, NFI =.898, CFI =.969, IFI =.970, TLI =.959, RMR =.058. The results demonstrated that the data reasonably fitted the model. We also examined construct reliability and reliability and average variance extracted (AVE). The construct reliability of each construct was greater than.80 and the AVE of each construct was greater than.50. According to the analysis of Structure Equation Modeling (SEM), the results of path model indicated an adequate fit of the model: $X^2$= 142.126, p = 0.044, d.f. = 115, GFI =.892, NFI =.909, CFI =.981, IFI =.981, TLI =.974, RMR =.057. As hypothesized, the results showed that it is strategically important to establish trust in a franchise system, and the franchisor's supports, communication and satisfaction with previous outcome tend to reinforce franchisee's trust. The results also showed trust seems to decrease as the experience of conflict episodes increases. And we also noticed that franchisor's supports and communication tend to enhance the franchisee's satisfaction with previous outcome, and communication tend to decrease conflict. If the trust between the franchisor and franchisee can be established in a franchise system, franchising offers many benefits and reduces many costs. To manage a mutual trust of relationship with their franchisees, franchisor's should provide support effectively to their franchisees. Effective assistant services have direct effect on franchisees' satisfaction with previous outcome and trust in franchisor. Especially, franchise sales process, orientation, and training in the start-up period are key elements for success of the franchise system. Franchisor's support is an accumulated separate satisfaction evaluation with different kind of service provided by the franchisor. And providing support definitely can improve the trustworthy image of the franchisor. In the franchise system, conflicts of interests and exertions of different power sources are very common. The experience of conflict episodes seems to negatively relate to trust. Therefore, it is important to reduce the negative side of the relationship conflicts. Communication actually plays a broader role in reducing conflict and establish mutual trust in franchisor-franchisee relationship. And effective communication between franchisors and franchisees can improve franchisees' satisfaction toward the franchise system. As the diversification of Chinese markets, both franchisors and franchisees must keep the relevant, timely, and reliable communication. And it is very important to improve the quality of communication. Satisfaction with precious outcomes seems to positively relate to trust. Franchisors and franchisees that are highly satisfied with the previous outcomes that flow from their relationship will perceive their partner as advancing their goal achievement. Therefore, it is necessary for both franchisor and their franchisees to make the welfare of partner with effort. Little literature has focused on what factors affect the trust between franchisors and their franchisees in China. This study developed the hypotheses regarding the factors affecting trust in the transaction relationship. The results of data analysis supported the hypotheses strongly. There are certain limitations in this study. First, we may point out that some other factors missed in this study could be significantly important. Second, the context of this study, food service industry, limits its potential generalizability for all franchise systems. More studies in different categories of franchise system are needed to broaden its generalizability. Third, the model was tested empirically in a sample in Beijing, more empirical tests of the proposed model in other Chinese areas are needed. Finally, the analysis in this study was solely based on the perception of franchisees and the opinions of franchisors were not included.

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A Study on Interactions of Competitive Promotions Between the New and Used Cars (신차와 중고차간 프로모션의 상호작용에 대한 연구)

  • Chang, Kwangpil
    • Asia Marketing Journal
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    • v.14 no.1
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    • pp.83-98
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    • 2012
  • In a market where new and used cars are competing with each other, we would run the risk of obtaining biased estimates of cross elasticity between them if we focus on only new cars or on only used cars. Unfortunately, most of previous studies on the automobile industry have focused on only new car models without taking into account the effect of used cars' pricing policy on new cars' market shares and vice versa, resulting in inadequate prediction of reactive pricing in response to competitors' rebate or price discount. However, there are some exceptions. Purohit (1992) and Sullivan (1990) looked into both new and used car markets at the same time to examine the effect of new car model launching on the used car prices. But their studies have some limitations in that they employed the average used car prices reported in NADA Used Car Guide instead of actual transaction prices. Some of the conflicting results may be due to this problem in the data. Park (1998) recognized this problem and used the actual prices in his study. His work is notable in that he investigated the qualitative effect of new car model launching on the pricing policy of the used car in terms of reinforcement of brand equity. The current work also used the actual price like Park (1998) but the quantitative aspect of competitive price promotion between new and used cars of the same model was explored. In this study, I develop a model that assumes that the cross elasticity between new and used cars of the same model is higher than those amongst new cars and used cars of the different model. Specifically, I apply the nested logit model that assumes the car model choice at the first stage and the choice between new and used cars at the second stage. This proposed model is compared to the IIA (Independence of Irrelevant Alternatives) model that assumes that there is no decision hierarchy but that new and used cars of the different model are all substitutable at the first stage. The data for this study are drawn from Power Information Network (PIN), an affiliate of J.D. Power and Associates. PIN collects sales transaction data from a sample of dealerships in the major metropolitan areas in the U.S. These are retail transactions, i.e., sales or leases to final consumers, excluding fleet sales and including both new car and used car sales. Each observation in the PIN database contains the transaction date, the manufacturer, model year, make, model, trim and other car information, the transaction price, consumer rebates, the interest rate, term, amount financed (when the vehicle is financed or leased), etc. I used data for the compact cars sold during the period January 2009- June 2009. The new and used cars of the top nine selling models are included in the study: Mazda 3, Honda Civic, Chevrolet Cobalt, Toyota Corolla, Hyundai Elantra, Ford Focus, Volkswagen Jetta, Nissan Sentra, and Kia Spectra. These models in the study accounted for 87% of category unit sales. Empirical application of the nested logit model showed that the proposed model outperformed the IIA (Independence of Irrelevant Alternatives) model in both calibration and holdout samples. The other comparison model that assumes choice between new and used cars at the first stage and car model choice at the second stage turned out to be mis-specfied since the dissimilarity parameter (i.e., inclusive or categroy value parameter) was estimated to be greater than 1. Post hoc analysis based on estimated parameters was conducted employing the modified Lanczo's iterative method. This method is intuitively appealing. For example, suppose a new car offers a certain amount of rebate and gains market share at first. In response to this rebate, a used car of the same model keeps decreasing price until it regains the lost market share to maintain the status quo. The new car settle down to a lowered market share due to the used car's reaction. The method enables us to find the amount of price discount to main the status quo and equilibrium market shares of the new and used cars. In the first simulation, I used Jetta as a focal brand to see how its new and used cars set prices, rebates or APR interactively assuming that reactive cars respond to price promotion to maintain the status quo. The simulation results showed that the IIA model underestimates cross elasticities, resulting in suggesting less aggressive used car price discount in response to new cars' rebate than the proposed nested logit model. In the second simulation, I used Elantra to reconfirm the result for Jetta and came to the same conclusion. In the third simulation, I had Corolla offer $1,000 rebate to see what could be the best response for Elantra's new and used cars. Interestingly, Elantra's used car could maintain the status quo by offering lower price discount ($160) than the new car ($205). In the future research, we might want to explore the plausibility of the alternative nested logit model. For example, the NUB model that assumes choice between new and used cars at the first stage and brand choice at the second stage could be a possibility even though it was rejected in the current study because of mis-specification (A dissimilarity parameter turned out to be higher than 1). The NUB model may have been rejected due to true mis-specification or data structure transmitted from a typical car dealership. In a typical car dealership, both new and used cars of the same model are displayed. Because of this fact, the BNU model that assumes brand choice at the first stage and choice between new and used cars at the second stage may have been favored in the current study since customers first choose a dealership (brand) then choose between new and used cars given this market environment. However, suppose there are dealerships that carry both new and used cars of various models, then the NUB model might fit the data as well as the BNU model. Which model is a better description of the data is an empirical question. In addition, it would be interesting to test a probabilistic mixture model of the BNU and NUB on a new data set.

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