온라인 시장 활성화를 위한 간편결제 특성에 관한 연구

최수정,김창식,곽기영,김희웅,Choi, Sujung,Kim, Changsik,Kwahk, Keeyoung,Kim, Heewoong 디지털산업정보학회 2016 디지털산업정보학회논문지 Vol.12 No.3

This study develops an extended model to predict customer satisfaction in easy payment systems based on information systems success model. Our data was collected from easy payment systems users and analyzed using PLS. This study selected four variables as easy payment systems characteristics(convenience, variety, security, speed) along with gender being used as a moderating variable. The results showed that convenience and security are turned out to affect customer satisfaction. Additionally, the test of difference in gender revealed that with respect to gender, moderating effects exist in security and speed. This implies that this study can provide different promotion strategies according to gender. Overall, the proposed model could be used to predict customers' willingness to pay on the easy payment systems.

Hedge Fund Returns and Total Factor Productivity

Sujung Choi(최수정) 한국증권학회 2024 한국증권학회지 Vol.53 No.2

본 연구는 구조적 벡터자기회귀 모형(SVAR)과 벡터오차수정 모형(VECM)을 이용하여 헤지펀드들의 투자 행태가 거시 경제적 총요소생산성의 변화를 예측할 수 있는지 살펴보았다. 즉, 주식 시장의 정보 보유 거래자(informed traders)로써 헤지펀드는 다른 투자자들보다 시장 분석에 있어서 더 우월한 능력을 가지고 있다고 알려져 있으며, 이에 헤지펀드들이 거시 경제적 생산성의 향상과 관련된 뉴스 충격을 선제적으로 포착하고 대응할 수 있는지 확인하였다. John Fernald(2014)가 산출한 미국의 분기별 TFP 자료와 크레딧 스위스/트레몬트 데이터베이스에서 제공하는 헤지펀드 지수(HFI)의 수익률 자료를 활용하여 1994년 1분기부터 2023년 2분기까지의 표본 기간 동안 두 내생 변수 간의 시계열적 연관성을 검토하였다. 분석기간 두 변수의 동 분기 상관계수는 0.9791로 나타나 두 변수의 움직임에 유사성이 매우 높다는 것이 확인되었다. 그랜저 인과관계 검정 결과, “ ΔLn(HFI ) 가 ΔTFP 를 그랜저 인과하지 않는다”라는 가설이 기각되었으며 이는 헤지펀드들의 행태를 보여주는 헤지펀드 수익률 정보가 총요소생산성의 변화를 예측하는 데 유용하다는 것을 암시한다. 마지막으로, VECM 모델을 사용한 예측오차 분산분해에 따르면 ΔLn(HFI ) 에 대한 충격이 20분기 이후에도 ΔTFP 변동의 65% 이상을 설명하는 것으로 나타났다. This study explores whether hedge funds’ investment behavior can predict variations in productivity levels using a structural vector autoregressive model (SVAR) and a vector error correction model (VECM). As informed traders in the stock market with superior skills, hedge funds may quickly capture news shocks regarding future production growth in advance. With quarterly series of TFP provided by John Fernald (2014) and hedge fund index (HFI) returns obtained from the Credit Suisse/Tremont database, I find a contemporaneous correlation coefficient of 0.9791 between two endogenous variables over the sample period from 1Q:1994 to 2Q:2023, indicating a high degree of similarity in their movements. A Granger Causality Test rejects the hypothesis, “ ΔLn(HFI ) does not Granger Cause ΔTFP ”, suggesting that the information inferred from the hedge fund index are valuable in predicting future economic productivity. Finally, the forecast error variance decompositions using the VECM model indicate that over 65% of the variation in ΔTFP even after 20 quarters can be attributed to a shock to the ΔLn(HFI) .

성별·연령대별 특성에 따른 위험자산 선택요인 분석

최수정(Sujung Choi) 한국자료분석학회 2022 Journal of the Korean Data Analysis Society Vol.24 No.5

본 연구는 통계청에서 최근 공개하기 시작한 퇴직연금 승인형 마이크로데이터서비스(MDIS)를 분석하여 퇴직연금 가입유형 중 하나인 IRP(Individual Retirement Pension) 가입자들을 대상으로 위험자산(실적배당형 상품)을 보유하고 있는 가입자들의 특성을 파악하였다. 이는 IRP 가입자들, 더 나아가 전체 퇴직연금 가입자들의 중장기 수익률 제고를 위해 정책적으로 집중해야 할 대상군을 살펴보고 가입자들의 자산 배분 현황을 파악하여 제도의 실효성을 높이는 데 그 목적이 있다. IRP 가입기간, 성별 및 연령대를 중심으로 살펴보았으며, 2017년 IRP 가입 대상 확대의 제도변경에 따라 각 특성변수의 위험자산선택 확률에 변화가 있는지 연도별 logistic regression의 odds ratio 및 marginal effect를 비교하였다. 개인형 IRP 계좌 보유자는 2015년 745,801명에서 2020년 2,444,765명이 되어 3.28배 증가하였고 그 중 위험자산 보유 가입자도 4.73배 증가하였다. IRP 계좌 유지 기간의 중앙값의 경우 2017년을 기점으로 2015년 0년에서 2020년 2년으로 증가하여 신규 유입된 IRP 가입자들은 이전 가입자들보다 계좌를 더 길게 유지하는 경향을 보였다. 위험자산 보유확률은 제도변경과 관계없이 남성이 여성보다 2015년(2020년)에는 약 4.72%(2.58%) 높아 남성이 여성보다 위험자산을 더 선호하는 현상이 일관성 있게 나타났다. This study investigates the determinants of investing in risky assets by IRP(individual retirement pension) holders. The KOSIS(Korean Statistical Information Service) recently started to provide individual-level annual microdata on retirement pension holders from 2015 to 2020 through Microdata Integrated Service(MDIS). The microdata includes all nationwide retirement pension holders with their demographic information such as gender and age. Using the microdata, this study examines the IRP tenure, gender, and age factors which could be related to the investors’ behavior of choosing risky products such as stocks and bonds relative to risk-free assets(i.e., time deposits). In particular, the number of IRP holders has dramatically increased because of the changes in regulation that allows special occupation pension holders and self-employed persons to join the IRP since 2017. The total number of IRP holders was 745,801 in 2015 and became 2,444,765 in 2020; the number of IRP holders who have a balance of risky assets in their accounts has also increased 4.73 times more in 2020 than in 2015. We compare odds ratios and marginal effects by employing the annual cross-sectional logistic regressions and find that the probability of investing in risky assets is 4.72%(2.58%) higher for male IRP holders than for female IRP holders in 2015(2020). Newly joining IRP holders since 2017 are more likely to keep their accounts than prior IRP holders; 20s and 30s IRP holders in 2019 and 2020 are more interested in choosing risky products than before.

모바일 간편결제에 대한 지속사용의도: 개인의 혁신성, 신뢰 및 네트워크 효과를 고려한 UTAUT모형 시각에서의 접근

최수정 ( Sujung Choi ),강영선 ( Yeong Seon Kang ) 정보통신정책학회 2016 정보통신정책연구 Vol.23 No.4

본 연구는 최근 급성장 하고 있는 모바일 간편결제에서 어떤 요인들이 이를 이용하는 사용자들의 지속사용의도에 영향을 미쳤는지 살펴보았다. 구체적으로 개인의 혁신성, 모바일 간편결제에 대한 지각된 신뢰, 네트워크 효과에 대한 기대가 사용자들의 지속사용의도에 미치는 영향을 분석하였다. 이를 위해, 본 연구에서는 Venkatesh et al. (2003)의 UTAUT모형(Unified Theory of Acceptance and Use of Technology)을 적용하여 새로운 기술을 수용하는 사용자의 지속사용의도를 설명하고자 한다. 207명의 대학생을 대상으로 설문을 실시했으며, smartPLS를 통해 분석한 결과, UTAUT모형으로부터 성과기대, 노력기대, 사회적영향이 모바일 간편결제 사용자의 지속사용의도에 긍정적인 영향을 미치는 것으로 나타났으며, 본 연구를 통해 추가된 지각된 신뢰, 네트워크 효과에 대한 기대가 모바일 간편결제 사용자의 지속사용의도에 긍정적인 영향을 미치는 것으로 나타났다. 하지만, 모바일 간편결제 사용자의 혁신성은 지속사용의도에 유의한 영향을 미치지 않는 것으로 나타났다. In this study, we investigate various factors affecting technology acceptance by smartphone users (i.e., perceived trust, perceived network effects, and users` innovativeness) in relation to mobile payment services, which have recently been introduced in Korea. For this purpose, we employ the unified theory of acceptance and use of technology (UTAUT; Venkatesh et al., 2003) to explain the process of technology adoption and user experience in the case of the new mobile payment services. A smartPLS-software analysis based on a survey of 207 undergraduate students indicates that five factors including performance expectations, effort expectations, social influence, perceived network effects, and users` innovativeness influence the intention of smartphone users to use mobile payment services continuously.

ETF Stock Return Predictability, Fund Premia, and Fund Flows

최수정(Sujung Choi) 한국자료분석학회 2020 Journal of the Korean Data Analysis Society Vol.22 No.1

This study examines time-series dynamics among ETF stock returns, fund premia, and fund flows in the Korean market. In particular, we focus on two hypotheses, ETF stock return predictability and return chasing behavior by ETF investors. We obtain daily ETF trading data from the DataGuide and analyze the whole ETFs traded for more than 250 days from January 1, 2009 to October 18, 2019. The ETF sample is comprehensive, consisting of 442 ETFs including domestic stock ETFs, domestic bond ETFs, foreign stock ETFs, and so on. A panel Granger causality test, VAR and panel fixed-effect models are employed to identify a bivariate relationship among those variables. We find that ETF stock returns today are negatively related to previous-day fund premia. Interestingly, lagged ETF fund sizes or fund inflows are also negatively associated with current ETF stock returns, which is similar with the case of actively managed funds facing decreasing returns to scale, although stock-picking ability is not necessary for the managers of passively managed funds such as ETFs. In addition, positive lagged ETF stock returns predict current fund outflows, implying that ETF investors in Korea are more likely to be short-term reversal traders and different from return-chasers in the US fund market.

국내상장 미국 주식형 상장지수펀드(ETF)의 성과요인 분석: 투자자 관점에서의 고찰

최수정(Sujung Choi) 한국FP학회 2024 Financial Planning Review Vol.17 No.3

최근 기술의 발전으로 해외 금융시장에 대한 정보의 접근성이 높아짐에 따라 개인 투자자들의 해외자산 투자에 대한 관심이 증가하고 있다. 이는 개인이 보유한 자산의 분산 투자를 효과적으로 달성한다는 측면에서 바람직한 현상일 수 있다. 특히, 퇴직연금이나 연금저축 계좌 등을 활용한 중장기 투자가 이루어진다면 국내상장 해외 주식형 ETF는 개인 투자자들이 선택할 수 있는 합리적이고 필수적인 투자안이 될 것이다. 그러나 투자자들의 관심 확대에도 불구하고 지금까지 해외 주식형 ETF의 성과요인을 분석한 연구는 자료 축적의 미비로 거의 이루어지지 못했다. 그럼에도 불구하고 본 연구는 2010년 10월부터 2024년 5월 말까지 미국 주식형 ETF의 일별 수익률 자료를 분석하여 개별 ETF의 성과에 영향을 미치는 요인들을 검토했다. 즉, 연도 및 개별 ETF를 고정효과로 하는 패널 이 중 고정효과 모형을 활용하여 투자자가 부담해야 하는 명시적 비용과 ETF의 유동성을 나타내는 Bid-Ask Spread에 대해, 투자비용이 수익률에 미치는 영향을 분석하였다. 명시적 비용 또는 Bid-Ask Spread가 증가하는 경우 시장가격 기준 수익률에 대한 민감도가 NAV 기준 수익률에 대한 민감도보다 더 높았다. 즉, 시장에서 투자자들은 ETF의 투자비용이 증가하는 경우 NAV로 측정되는 본질적 가치변동보다 더 크게 움직이는 것(overreaction)으로 판단된다. 추가적으로 환 헤지형 ETF와 환 노출형 ETF를 비교한 결과, 환 노출형 ETF의 성과가 더 우수했으며 환 헤지로 인한 수익의 감소는 연율로 환산하는 경우 NAV(시장가격) 기준 약 4.9%(4%) 정도였다. ETF 구성과 복제형태에 대해서는 실물(패시브), 합성(패시브), 실물(액티브)의 순서로 수익률이 높았다. Recent advances in technology have increased the accessibility of information about overseas financial markets, leading to an increase in individual investors’ interest in investing in foreign assets than in the past. This trend can be beneficial for effectively achieving diversification of financial assets held by individual investors. In particular, for mid- to long-term investments, such as those made through retirement deposits or pension accounts, domestically listed foreign stock exchange-traded funds (ETFs) are a reasonable and necessary investment option. However, despite the growing interest, few studies have analyzed the factors influencing the performance of foreign equity ETFs due to a lack of accumulated data. This study aims to identify the factors affecting the performance of domestically listed U.S. equity ETFs by analyzing daily returns from October 2010 to May 2024. Using a panel two-way fixed-effect model with year and individual ETFs as fixed effects, we consider both explicit costs from the investors perspective and the bidask spread as a proxy for implicit costs related to ETF liquidity. We find that NAV-based returns are more sensitive to costs than market price-based returns. This suggests that in the market, investors tend to overreact, responding more significantly to changes in investment costs than to intrinsic value fluctuations measured by NAV. Additionally, when comparing hedged ETFs to unhedged ETFs relative to the USD/KRW exchange rate, unhedged ETFs performed better. The reduction in returns from hedging was significant, around 4.9%(4%) on an annualized NAV(market-price)-based return. Regarding ETF composition and replication methods, performance ranked highest in the order of physical (passive), synthetic (passive), and physical (active) ETFs, especially when assessed on a NAV basis.

지리가중회귀 모형을 이용한 지역별 특성화고등학교 취업률 영향요인 분석

민지식(Min, Jisik),최수정(Choi, Sujung) 한국직업교육학회 2021 職業 敎育 硏究 Vol.40 No.4

이 연구는 지리가중회귀(GWR) 방법을 활용하여 특성화고등학교 졸업생의 취업률에 영향을 미치는 요인이 무엇이고, 그 중에서도 지역적인 수준의 영향요인이 어떠한지 확인하는 데 목적이 있다. 지리가중회귀 분석 방법은 주로 지역의 노동시장에 대한 분석에 주로 활용되는 방법이나 최근에는 교육, 환경 등 다양한 분야에서 활용되고 있다. 취업률과 같은 노동시장 성과는 지역에 따라 크게 차이를 보일 수 있으며 인근의 유관산업이나 노동시장 환경 등에 영향을 받는다는 선행연구들이 제시되고 있다. 따라서 취업률 측면에서도 지역 수준의 논의가 이루어지는 것이 상당히 중요하지만 기존의 선행연구들에서는 전국 단위에서 취업률을 분석한 경우는 거의 없는 것으로 나타났으며, 지역의 특성을 반영하여 연구가 수행되지 못했다는 한계가 있었다. 이러한 맥락에서 이 연구에서는 지역 수준을 관측치로 하여 분석을 수행하였으며, 분석 결과 일반적인 최소자승법(OLS) 모형보다 공간적 이질성을 고려한 지리가중회귀 모형이 보다 적절한 것으로 나타났다. 결과적으로는 제조업비율, 지역 내 성비, 특성화 분야의 취업비율 등의 지역 변인들이 큰 영향을 미치는 것으로 나타났으며, 유의한 변인들의 계수 크기가 지역에 따라 다른 패턴을 나타내는 것을 확인하였다. 이러한 변인들은 학교 수준에서 취합된 데이터로, 결과적으로 개별 학교의 취업률에는 학교 관련 변인이 큰 영향을 미칠 수 있으나 지역 수준의 자료에서는 지역적인 특성이 더 크게 영향을 미친다고 해석할 수 있었다. 이러한 결과를 바탕으로 지역 정책에 대한 제언 및 후속연구에 대한 제언을 제시하였다. This study aims to identify which factors affect the employment rate of graduates of specialized high schools by utilizing the Geographically weighted Regression(GWR) method, among others, and what local-level influences are. regression analysis considering spatial dependency are mainly used to analyze the local labor market but has recently been used in various fields such as education and the environment. Prior studies suggest that labor market performance, such as the employment rate, can vary greatly depending on the region and is affected by related industries or the labor market environment nearby. Therefore, while it is quite important to have regional-level discussions in terms of employment rates, existing prior studies showed that few employment rates were analyzed at the national level, and there was a limitation that studies were not conducted to reflect local characteristics. In this context, we analyzed with region-level observations, and our analysis shows that Geographically weighted Regression(GWR) is more appropriate than typical OLS models. As a result, variables at the regional level, such as manufacturing ratios, gender ratios in the region, and employment ratios in the specialization sector, have to deal with more important factors as a point of spatial analysis. We also confirmed that the coefficient size of significant variables represents a pattern that varies by region. These results allowed us to interpret that local characteristics had a larger impact on local-level data rather than school-level variables, suggestions for local policies, and suggestions for follow-up studies.

한국 채권시장의 Shadow Rate 추정과 금융시장에 미치는 영향

이정인(JungIn Lee),최수정(Sujung Choi),이준희(Joon-hee Rhee) 대한경영학회 2017 大韓經營學會誌 Vol.30 No.3

육군실내사격장 고무판 탄두회수시설 설치 후 납(РЬ)노출 실태 조사

이종태 ( Lee Jongtae ),최수정 ( Choi Sujung ) 국군의무사령부 2017 대한군진의학학술지 Vol.48 No.1

Objectives: As bullet hit steel plate-type bullet recovery facility, the lead inside bullet is scattered in the form of dust. Thus, it was founded that workers who manage indoor firing range were poisoned with lead. To solve the lead dust problem and to normalize the indoor shooting range, the army installed rubber plate-type bullet recovery facility at army indoor firing range. By investigating lead concentration in air in indoor shooting range and actual lead exposure of fire controllers, we intend to apply the results to reduce lead exposure and improve ventilation facilities. Methods: Targeting 12 units of the army indoor firing range, we measured lead concentration during shooting training depending on the individual and the area. Personal lead concentration samples were corrected from instructor, safety controllers, ammunition manager, assistants, and shooters, during shooting practice. The area samples were divided into three areas (Fire area, trajectory-area, and target area), and lead concentration by location was measured. Measurement and analysis methods followed the KOSHA GUIDE A-2-2015 guidelines. Results: By replacing with rubber plate-type bullet recovery facility, lead dust in target area was significantly reduced. In addition, in rubber plate-type bullet recovery facility system, the entire amount of bullet can be recovered, which has the advantage of resource recycling. However, the exposure lead concentration of fire controllers did not decrease significantly after installing. Conclusions: Because the fire controllers are located at a distance or 25m or more apart from the target area, so it is not affected by lead dust occurred from target area. The fire controllers are exposed to lead dust contained in the percussion gas during shooting, thus it is affected by shooting frequency and ventilation facility, rather than type of plates. To reduce the fire controller's lead exposure, first, it is necessary to increase the capacity of the ventilation facility to discharge the percussion gas to the outside. Second, lead, a hazardous substance, must be replaced by another substance. The environmentally bullet or TMJ (Total Metal Jacket) that replaced lead with copper should be introduced to prevent lead dust generated from firing. It is urgent to improve the army indoor firing range, which is not enough for ventilation, through establishing the design standard for ventilation facility to be applied to indoor firing range.

중국 주식시장에서 역행투자전략의 성과에 대한 실증적 연구

박훈 ( Piao Xun ),최수정 ( Sujung Choi ) 아시아.유럽미래학회 2016 유라시아연구 Vol.13 No.3

The contrarian strategy based on historical stock prices is a well-known market anomaly contradicting the weak-form market efficiency. Debondt and Thaler(1985) provide an evidence on the contrarian strategy that can generate cumulative abnormal returns relative to the market index by analyzing monthly return data of the New York Stock Exchange common stocks from January 1926 to December 1982. They argue that the overreaction of investors to the unexpected and dramatic new information would cause the overshooting of stock prices in the short-term, so the stock prices would reverse to the fundamental level when investors realize their mistakes in the long-term. However, there also exist studies arguing time-varying systematic risk, not overreaction of investors, is a main reason of the return reversal phenomenon in the long-term. In fact, both the overreaction of investors and time-varying systematic risk would partly contribute the historical patterns of stock returns such as short-term momentum and long-term reversal phenomena. The contrarian strategy is a trading strategy of selling winners and buying losers, and holding the portfolio for around 3 to 5 years since the long-term return reversal often occurs in the market. Similarly, the momentum strategy is to buy winners and sell losers with a less than 1-year holding period, which is based on the short-term continuation of stock returns. In the studies of U.S. stock market data, both trading strategies are known profitable and argued as a prima facie evidence on the weak-form market efficiency. The economy of China has remarkably been growing since the market was opened up to the rest of the world in 1978. As of June 2015, the Shanghai Stock Exchange(SSE) exhibits notable statistics such as 1,081 companies listed, 5,914 stocks traded, and $5.9 trillion of a market capitalization; and the Shenzhen Stock Exchange(SZSE) founded in 1991 also records 1,746 firms offered, 3,440 stocks traded, and $4.4 trillion of market capitalization. Recently, China Securities Regulatory Commission tries to promote foreign investors to invest in the Chinese Stock Market by introducing new policies such as the Shanghai-Hong Kong Stock Connect. Especially, Korean Economy is closely connected to the economy of China, so it would be interesting to study the market efficiency of the Chinese Stock Market. This study investigates the contrarian strategy in Chinese stock market from 2000 to 2014 by employing the market-adjusted model and the risk-adjusted model. We construct the winner and loser portfolios using cumulative abnormal returns of individual stocks following the methodology of De Bondt and Thaler (1988). The upper and lower 20% individual stocks based on previous 3-year excess returns consist of the winner and loser portfolios. Overall, the empirical results support the contrarian strategy regardless of the performance measure such as the market-adjusted model and the risk-adjusted model. That is, the contrarian strategy selling winners and buying losers based on previous 3-years cumulative abnormal returns produces economically and statistically significant abnormal returns at the Chinese Stock Market in the following 1- to 3-year holding periods. Interestingly, the trading strategy is more profitable in the Shanghai Stock Exchange than in the Shenzhen Stock Exchange.