• Journal of the Korean Institute of Telematics and Electronics B
• /
• v.31B no.8
• /
• pp.11-19
• /
• 1994

The matching probability P(ο/$\lambda$), of the signal sequence(ο) observed for a finite time interval with a HMM (Hidden Markov Model $\lambda$) indicates the probability that signal comes from the given model. By utilizing the fact that the probability represents matching score of the observed signal with the model we can recognize an unknown signal pattern by comparing the magnitudes of the matching probabilities with respect to the known models. Because the algorithm however uses floating point variables during the computing process hardware implementation of the algorithm requires floating point units. This paper proposes an integer algorithm which uses positive integer numbers rather than float point ones to compute the matching probability so that we can economically realize the algorithm into hardware. The algorithm makes the model parameters integer numbers by multiplying positive constants and prevents from divergence of data through the normalization of variables at each step. The final equation of matching probability is composed of constant terms and a variable term which contains logarithm operations. A scheme to make the log conversion table smaller is also presented. To analyze the qualitive characteristics of the proposed algorithm we attatch simulation result performed on two groups of 10 hypothetic models respectively and inspect the statistical properties with repect to the model order the magnitude of scaling constants and the effect of the observation length.

• Women's Health Nursing
• /
• v.19 no.2
• /
• pp.75-87
• /
• 2013

Purpose: In this study effects of a paternal participation program during cesarean section on paternal infant attachment were investigate. The experimental treatment was an integrative nursing intervention to promote father to infant attachment. Methods: Study design was a non-equivalent control group posttest design. The program consisted of emotional support to spouse and father towards infant attachment immediately following cesarean birth. Participants were 66 men, partners of women with normal full term pregnancy having a cesarean section with spinal or epidural anesthesia, (experimental group, 34; control group, 32). The experiment was carried out from August 1 to October 30, 2010. Control group data were obtained from May 1 to June 30, 2012. Posttest was performed 72 hours after cesarean birth. A self-report questionnaire including a paternal attachment instrument was used. Data were analyzed using t-test, propensity score matching, and analysis of covariance with the SPSS/WIN 18.0 program. Results: Total score for paternal infant attachment in the experimental group was significantly higher than the control group (p<.001). After matching, significant differences were found between the two groups through all subcategories. Adjusted mean score for paternal infant attachment verified experimental effects. Conclusion: Results indicate that this paternal participation program during cesarean section is effective in improving paternal infant attachment.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.7 no.2
• /
• pp.133-138
• /
• 2013

This study was aimed to examine effects of the assistive technology program that has purpose to maintain and promote employment of persons with disabilities. An administrative data constructed by the Korea Employment Agency for the Disabled(KEAD) was utilized. Propensity score matching were used as analysis methods to minish sample selection bias caused by nonrandom sampling. As a result, turnover rate of people with disabilities who used assistive technology device was lower compared to persons with disabilities did not use assistive technology device. Also, in terms of company, for employment promotion effect on the persons with disabilities, company that provided assistive technology device was higher than that of company did not provide assistive technology device. Finally, assistive technology devices were effective in the employment area was confirmed.

• 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 the Korea Academia-Industrial cooperation Society
• /
• v.10 no.1
• /
• pp.200-208
• /
• 2009

Trend of R&D expenditure in Korea during the last 10 years, the R&D expenditure has been constantly increasing at an average rate of 10%. The government R&D ekpenditures or subsidies are increasing rapidly But the studies of evaluating impact of government R&D subsidies are few. This study attempts to empirically investigate the effects of government R&D subsidies on private firm's R&D investment in Korean industry by using Propensity score matching method which sign as to whether the relationship between government subsidies and private R&D investments is on stimulating or displacing private R&D expenditures. Empirically, a firm with government R&D subsidy are 733 million dollar more expenditure then don't receive any government R&D funding. Also Government R&D subsidies greatly increase (statistically significant) company financed R&D expenditures only for large firms but had no effect on the R&D expenditures of small & medium sized firms and venture firms.

• Journal of Korean Society for Quality Management
• /
• v.44 no.2
• /
• pp.341-356
• /
• 2016

Purpose: The purpose of this paper is to study whether the adoption of Six Sigma quality management by a firm positively affects its financial performance. The correlation between the duration of Six Sigma implementation period and the financial status of the firm is investigated as well. Methods: We conduct the analysis using data from Manufacturing Industry Productivity Panel Survey 2013 provided by Korea Productivity Center and Ministry of Trade, Industry and Energy. Propensity score matching is used to reduce sample selection bias of observational study. Furthermore, we use multiple linear regression in order to study the relationship between the implementation of Six Sigma quality management and financial performance. The return on assets and ratio of net income to net sales are considered as dependent variable and implementation of Six Sigma as independent variable. Results: The indication of this analysis is that implementation of Six Sigma quality management does not significantly enhance financial status. The firms that adopted Six Sigma quality management were categorized into three groups according to the implementation period. Comparison of each group with the firms that do not adopt Six Sigma quality management does not show statistically significant enhancement of financial status. Conclusion: In conclusion, both adoption and duration of six sigma quality management do not affect financial performance significantly.

• Journal of Labour Economics
• /
• v.43 no.3
• /
• pp.33-61
• /
• 2020

The purpose of this study is to analyze the disparity in on-the-job training between regular and non-regular workers and to compare the wage effects of on-the-job training. Using the Korean micro data from the Programme for the International Assessment of Adult Competencies(PIAAC) published by OECD, Propensity Score Method(PSM) is applied to overcome the endogeneity problem. The average treatment effect(ATT) on the training participation is analyzed, using non-regular workers as treatment group and regular workers as comparison group. Odds ratios of non-regular employees' training participation compared to regular employees shows 0.67 times after constructing matching sample and this means that non-regular workers are facing a disadvantageous training opportunity compared to regular workers. In order to estimate the wage effect of on-the-job training, the average treatment effect(ATT) of on-the-job training on average wages for regular workers and non-regular workers is estimated respectively. I find insignificant wage effect from on-the-job training among regular workers and significant positive effect on non-regular worker's wage from on-the-job training.

• Journal of Technology Innovation
• /
• v.24 no.3
• /
• pp.29-52
• /
• 2016

As Industry-University Cooperation (IUC) has been emphasized for securing national competitiveness in a knowledge-based economy, the South Korean government has promoted related policies, including a financial support program for facilitating IUC activities. This study examines the effects of Leaders in INdustry-university Cooperation (LINC) program, which is one of the government financial support programs for IUC, on the performance of IUC by propensity score matching. The results show that LINC program positively influences the number of technology transfers and the number of faculty that participated in start-ups. The results of this study are expected to provide implications for improving IUC policies and the financial support program.

• Korean Journal of Social Welfare Studies
• /
• v.44 no.3
• /
• pp.5-30
• /
• 2013

The aim of this study is to identify the influence of public housing on depression of its residents by analyzing the 7th Korea welfare panel study. To reduce the selection bias which arise from the public housing is selected by personal choice, we used PSM(propensity score matching). In addition, we merged the result of PSM and OLS regression to control the other variables which can affect depression of the resident of public housing. Final result revealed that the statistical significance which was observed when we compared the level of depression between the residents of public housing and general community by independent t-test was not observed when we used the merged result from PSM and regression. These results suggest that the high level of depression in the residents of public housing might be related with their demographic characteristics or earned income not with the public housing itself. This study can be the evidence supporting the policy of providing public housing because living in public housing did not give negative influence on its residents. Considering that this study also showed that there were no observable positive influences of public housing, we can suggest that public housing policy for majority of people not limited to people with low income.

• The Journal of the Korea Contents Association
• /
• v.19 no.10
• /
• pp.667-676
• /
• 2019

The purpose of this study was to assess the impact of childbirth on socioeconomic status changes of women. Data were collected from Korean Health Panel (2008-2015). A difference-in-differences model with propensity score matching was applied to assess the impact of childbirth on socioeconomic status changes. As a result, variables showing significant differences in the interaction terms indicating the impact of birth were the savings, economic activity, and occupational status. The impact of birth were significant in decreasing the amount of savings and negatively affecting women's economic activities, but in increasing the probability of full-time and regular employees in occupational status. Childbirth appears to have a negative impact on the home economics and socioeconomic status of women. The belief that home economies can be stabilized even after childbirth should be established, and a long-term and sustained support plan should be set up to realize this belief.