• 한국노년학
• /
• v.38 no.3
• /
• pp.481-499
• /
• 2018

The purpose of this study is to examine the impacts of smartphone use on structured social network types in the Korean elderly population. Data was derived from the 2014 survey of living conditions and welfare needs of Korean older persons collected by Korea Institute for Health and Social Affairs. A total of 4,180 participants were selected for the Propensity Score Matching (PSM) analysis. Based on propensity score estimates, the 491 smartphone users (treatment group) and 491 featurephone users (control group) were matched. Ordinary Least Squares (OLS) regression analysis was conducted to examine the relationship between smartphone use and structural social network types. The results showed that among retired older adults, people using smartphone had significantly better structured social networks than those using featurephone even after controlling for covariates. Smartphone users had the higher levels of social contact and social activity. These findings suggested empirical evidence that using smartphone positively affects structured social networks, which might be used as the basis for designing intervention programs to promote social networks and social engagement of retired older adults.

• Journal of Korea Society of Industrial Information Systems
• /
• v.28 no.1
• /
• pp.57-69
• /
• 2023

In a situation where digital transformation using artificial intelligence is active around the world, the growth of domestic AI companies or AI industrial ecosystems is slow. Where a large amount of government funds related to AI are being invested to overcome the difficult economic situation, systematic research on the effect is insufficient. So, this study aimed to examine the policy effectiveness of the government artificial intelligence solution voucher support project for small and medium-sized enterprises (SMEs) using Propensity Score Matching (PSM) and Difference-in-Differences (DID) on the financial performance of beneficiary companies. For empirical analysis, PSM-DID analysis was performed using sales performance since 2019 for 461 companies with a history of voucher support among the AI SMEs data released by the National IT Industry Promotion Agency. As a result of the analysis, the beneficiary companies' asset growth, salary, and R&D expenses increased overall after government support, and no significant contribution could be confirmed in terms of profits. This study suggests that the voucher policy business directly contributed to the company's growth in the short term, but it requires a certain period of time to generate profits.

• Journal of Gastric Cancer
• /
• v.24 no.2
• /
• pp.220-230
• /
• 2024

Purpose: Prevention of pancreas-related complications after gastric cancer surgery is critical. Polyglycolic acid (PGA) mesh reduces postoperative pancreatic fistula formation following pancreatic resection. However, the clinical efficacy of PGA mesh in gastric cancer surgery has not been adequately investigated. Materials and Methods: This retrospective study compared the short-term outcomes between two groups: patients who underwent minimally invasive R0 gastrectomy for gastric cancer with the use of a PGA mesh (PGA group) and those without the use of a PGA mesh (non-PGA group) at the Cancer Institute Hospital, Tokyo, between January 2019 and May 2023. Propensity score matching (PSM) was performed to adjust for the possible confounding factors. Results: A total of 834 patients were initially included, of whom 614 (307 in each group) remained after PSM. The amylase levels in the drained abdominal fluid on postoperative days 1 and 3 were similar between the PGA and non-PGA groups. The PGA group had a significantly lower incidence of pancreas-related complications of Clavien-Dindo grade ≥2 than that in the non-PGA group (6.8% vs. 2.9%, P=0.025). In subgroup analyses, the odds ratio for pancreas-related complications appeared to be better in the PGA group than in the non-PGA group in patients with American Society of Anesthesiologists Physical Status Classification score of 2 or 3, those operated via a laparoscopic approach, and those undergoing procedures other than proximal gastrectomy. Conclusions: The use of PGA mesh significantly reduced pancreas-related complications after minimally invasive surgery for gastric cancer and might thus benefit patients at risk of such complications.

• The Journal of the Korea Contents Association
• /
• v.17 no.8
• /
• pp.382-395
• /
• 2017

This study tries to analyze whether the Earned Income Tax Credit (EITC), which was modified in 2011, has the effect of work incentive. In this sense, by establishing the 8th Wave of Korea Welfare Panel Study (2013) and the 9th Wave (2014), Furthermore, in order to overcome the methodological limit, the results of two-party analysis method will be compared by firstly carrying out multiple regression analysis and then performing propensity score matching analysis. The 535 households out of 6,025 were selected. The following are the results of multiple digression analysis and propensity score matching analysis. First, there was no statistically meaningful relationship with regard to the perception of the EITC. Second, there was a statistically meaningful result in the reduction of working hours with regard to whether a household received labor incentive or not. The study found that the revised EITC is not providing incentives which stimulates the will to work.

• Journal of Korean Society of Rural Planning
• /
• v.30 no.1
• /
• pp.81-97
• /
• 2024

This study examines the effects of adopting Information and Communication Technology (ICT) in livestock farm management on farm sales revenue. Using the 2020 Census of Agriculture, Forestry, and Fisheries, a nationally representative data set constructed by Statistics Korea, this study focuses on a sample of 9,020 livestock farms in South Korea. We employ Propensity Score Matching (PSM) methods to address the potential selection bias between 2,076 farms that used ICT for livestock farm management and 6,944 farms that did not. The findings consistently show that the use of ICT significantly increases farm revenue, taking into account the selection bias. The utilization of ICT in livestock farms leads to a higher increase in sales revenue, particularly for farms with greater sales.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.9
• /
• pp.3223-3231
• /
• 2010

For a long time, most of advanced countries have supported the innovative firms with various support methods such as tax credit, subsidy, human resource education, and so on. Tax credit for innovation is the most popular industrial policy in these countries including Korea. However, in Korea, the effect of tax credit policy has been rarely analyzed. On the other hand, a considerable number of studies discover that tax credit policy in other countries influences positively on invest of R&D expenditure. This paper shows that tax credit policy positively influences on firm's innovation performances in Korea. The evaluated innovative effect of tax credit policy in this paper is more persuasive because it introduces various innovation performance variables including patent application with Propensity score matching method(PSM).

• Journal of Engineering Education Research
• /
• v.20 no.3
• /
• pp.13-24
• /
• 2017

This study investigated student engagement of STEM-specialized higher education institutions in comparison with students from humanities & social science and STEM majors, respectively. By doing so, the study aimed to find the effects of the characteristics of STEM disciplines and organizational culture of STEM-specialized small-sized institutions on student engagement. The students majoring STEM disciplines, regardless of the organizational types, showed lower reflective-integrative learning experiences compared to students on humanities & social science disciplines. In contrast, students of STEM-specialized institutions reported significantly higher levels of peer relationship and student-faculty interaction in comparison with humanities & social science students and STEM students of general higher education institutions. Finally, the study suggests policy implications for STEM education.

• 한국사회정책
• /
• v.19 no.3
• /
• pp.85-117
• /
• 2012

This study attempts to examine the relationship between giving & volunteering behavior and charitable bequest intention. For the examination, this study used '2011 Korean National Social Survey' that was randomly sampled from the population of Korean in 2011. In examining the relationship, this study employed the method of Propensity Score Matching that permits the comparisons between experimental group and control group. In this study, the experimental groups consist of six different combinations of philanthropic behaviors as follows: donating only; volunteering only; participating both; regular donating only; regular volunteering only; and doing both regularly. The results show that all the types of philanthropic behaviors have statistically significant positive effect on charitable bequest intention. First, more active philanthropic behavior such as regular behavior causes higher charitable bequest intention. Second, those who participate in both philanthropic behaviors (combined behavior of donating and volunteering) have stronger effect on charitable bequest intention in comparison to participating only one philanthropic behavior (either donating or volunteering). Third, giving have relatively stronger relationship with charitable bequest intention than volunteering. Throughout more careful examination of the causal relationship from philanthropic behavior to charitable bequest intention, this study provides new understanding on the effect of daily philanthropic behavior on charitable bequest and practical implication to nurture charitable bequest. Indeed, this study contributes to building a knowledge foundation for future research on charitable bequest.

• Journal of Gastric Cancer
• /
• v.20 no.4
• /
• pp.431-441
• /
• 2020

Purpose: Various studies have indicated that reduced-port robotic gastrectomies are safe and feasible for treating patients with early gastric cancer. However, there have not been any comparative studies conducted that have evaluated patients with clinically advanced gastric cancer. Therefore, we aimed to compare the perioperative outcomes of D2 lymph node dissections during reduced-port robotic distal subtotal gastrectomies (RRDGs) and conventional 5-port laparoscopic distal subtotal gastrectomies (CLDGs). Materials and Methods: We retrospectively evaluated 118 patients with clinically advanced gastric cancer who underwent minimally invasive distal subtotal gastrectomies with D2 lymph node dissections between February 2016 and November 2019. To evaluate the patient data, we performed a 1:1 propensity score matching (PSM) according to age, sex, body mass index, American Society of Anesthesiologists physical status classification score, and clinical T status. The short-term surgical outcomes were also compared between the two groups. Results: The PSM identified 40 pairs of patients who underwent RRDG or CLDG. The RRDG group experienced a significantly longer operation time than the CLDG group (P<0.001), although the RRDG group had significantly less estimated blood loss (P=0.034). The number of retrieved extraperigastric lymph nodes in the RRDG group was significantly higher than that of the CLDG group (P=0.008). The rate of postoperative complications was not significantly different between the two groups (P=0.115). Conclusions: D2 lymph node dissections can be safely performed during RRDGs and the perioperative outcomes appear to be comparable to those of conventional laparoscopic surgeries. Further studies are needed to compare long-term survival outcomes.

• Journal of Korea Technology Innovation Society
• /
• v.13 no.4
• /
• pp.738-757
• /
• 2010

Generally, it is known that the agglomeration economies appear in some industry clusters which were developed naturally. But, in Korea, most of industry clusters were built by government. This research was carried out to evaluate the performance of governments zoning investment, in other words, industry cluster policy. In this research, we use the data of manufacturing firms in Kyunggi-province. For the microeconomic analysis, we use the KIS-VALUE data of 2008. As the empirical test methods we use both multiple regressions and Propensity Score Matching. In conclusion, there is no evidences that firms in industry cluster have better performances. Surprisingly, in PSM analysis, we find the evidence that firms in industry cluster show less innovative performance.