• Title/Summary/Keyword: proxy variables

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Dinophyceae Fluctuations in Two Alpine Lakes of Contrasting Size During a 10-Year Fortnightly Survey

  • Trevisan, R.;Pertile, R.;Bronamonte, V.;Dazzo, F.B.;Squartini, A.
    • Journal of Microbiology and Biotechnology
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    • v.22 no.6
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    • pp.754-762
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    • 2012
  • Colbricon Superiore and Inferiore are two small adjacent high-mountain lakes located in the Paneveggio Natural Park (Italy) that offer the rare opportunity to study two iso-ecologic water environments differing only by area and volume in a ratio of 2:1 and 3:1, respectively. We took advantage of this setting to investigate phytoplankton dynamics, compare variability and productivity differences between the two basins, and assess size-dependent issues. The phytoplankton group of the Dinophyceae was chosen as the indicator organisms of ecological perturbation owing to their high sensitivity to environmental variations, as well as their acknowledged nature of versatile proxy to report global climatic changes. The study was conducted for over 10 years with fortnightly samplings. Results indicated that (a) the Dinophyceae communities in the smaller lake were significantly more resistant to changes exerted by the fluctuation of lakewater transparency and pH; and (b) the smaller lake sustained a consistently higher production with an average Dinophyceae density 1.73 fold higher than that of the larger lake. The coefficients of variation show that the chemical parameters in the smaller lake display higher time-related fluctuation while being spatially homogeneous and that such conditions correlate with a higher stability of the Dinophyceae assemblage. The use of this setting is also proposed as a model to test relationships between ecosystem production and physical stability.

Market Structure and Standardization -An Empirical Study on Collective Standards in the Korean Industry- (시장구조와 표준화 - 우리나라 산업의 단체표준에 대한 실증적 연구-)

  • Sung, Tae-Kyung
    • Management & Information Systems Review
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    • v.33 no.4
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    • pp.63-75
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    • 2014
  • The paper investigates empirically the determinants of standardization activity at the industry level, focusing on market structure. The enactments or amendments of collective standards is used as the proxy variable for standardization activity. The independent variables, in addition to market structure, are technological opportunity, factor intensity, export ratio, and industry characteristics(assembly). We estimated the logistic regression model(so-called Logit), using the pooling data for 9 Korean industries, including foods, textiles, chemicals, nonmetallic minerals, metals, electronics and electrics, machinery, automobiles, and shipbuilding, over 2006-2009. The empirical finding shows that market structure has no any effects on the enactments or amendments of collective standards in Korea. This might infer that oligopolistic firms devote themselves to de facto standards determined by market rather than de jure standards such as collective standards and Korean Standards(KS). Besides market structure variable, whereas technological opportunity and assembly characteristics are likely to relate positively with the enactments or amendments of collective standards, capital intensity and export ratio have no any relationship with industrial standardization, respectively.

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Factors Influencing the Economic Status of the Elderly in Korea (우리나라 노인 빈곤의 원인에 관한 연구)

  • Hong, Baeg-Eui
    • Korean Journal of Social Welfare
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    • v.57 no.4
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    • pp.275-290
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    • 2005
  • This study investigates whether previous experiences in the labor market such as previous employment type and job type are related to the economic status and poverty in the elderly in Korea. Previous studies are limited in explaining the causes of poverty by using only the proxy variables such as age, marital status, and gender to classify the poverty status of the elderly after poverty has been identified. Therefore little is known about how the economic well-being after retirement is interrelated with previous job experiences in the labour market. The results indicate that the last job type and type of employment are significant predictors for the economic status of elderly. Job type in the labour market is critical for the lifetime economic status of an individual. These findings imply that we might need to reconsider the current public pension system which directly relates the benefit level to the amount of contribution. A system introducing a basic pension or a minimum pension benefit based on the citizenship or residence might be an alternative worth to consider.

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Information Risk and Equity Premium (정보위험과 주식수익률 프리미엄)

  • Park, Jong-Won;Yeoh, Hwan-Young
    • The Korean Journal of Financial Management
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    • v.27 no.1
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    • pp.209-237
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    • 2010
  • This paper examines the relationship between information risk and equity premium in the Korean stock market. We use accruals quality as a proxy of information risk. Accruals quality (AQ) is estimated by Dechow and Dichev (2002) model, and then AQfactor is constructed based on the estimated AQ. Time-series and cross-sectional regression models are used to examine the relationship between information risk and equity premium, reflecting the critics of Core et al. (2008). The result of the paper shows that information risk proxied by accruals quality is not priced in equity premium in the Korean stock market. This result is consistent with Core et al. (2008) for US firms, but different with Francis et al. (2005) for US firms and Gray et al. (2008) for Australia firms. Also, the result shows that AQfactor is closely correlated with firm characteristic variables such as firm size. This implies that the effect of AQ on equity premium is more likely to arise from the pricing error due to firm characteristics rather than from an unknown risk factor.

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A Study on the Effects of Entry Barriers for the Stock Prices of Venture Businesses. (진입 장벽이 벤처기업 주가에 미치는 영향)

  • Oh Sung-Bae;Kim Dong-Hwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.6 no.5
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    • pp.384-390
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    • 2005
  • The purpose of this study is to test empirically the effects of Entry Barriers for the stock prices of Venture Business using the Ohlson Model which is modifying and extending in terms of growth and the potential growth energy. Because the traditional Ohlson model(1995) on which the firm's value is determined only based on abnormal earnings and book value have numerous limitations when we evaluate the value of venture Businesses with high technology and new emerging market. In order to overcome these limitations, We can introduce items of net sales growth ratios and industrial property-to-net asset ratios into as proxy variables of the growth and potential growth energy. In the process of analyzing these research tests, we have set three kinds of hypotheses and tested then empirically compared with KOSDAQ ordinary listing business and KOSDAQ venture businesses between long-term analysis and short-term analysis. According to the degree of concentration reflecting HHI index, our empirical research were performed in depth. Therefore, the results of this study show us that all three kinds of Hypotheses are accepted.

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A Methodology for Finding the Convergence Research Area by Measuring Convergence Index in Government Research Institutes (융합지수 측정을 통한 출연연 융합연구영역 발굴모형 연구)

  • Coh, Byoung-Youl;Kim, So-Young;Lee, Jae-Min
    • Journal of Korea Technology Innovation Society
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    • v.22 no.3
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    • pp.446-474
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    • 2019
  • In conjunction with securing R&D competitiveness through technology convergence, there is a growing interest in the strategy to derive innovation based on the measurement of convergence. In this paper, we present a data-based model that suggests convergence strategies for the research projects of government research institutes (GRIs) in Korea. The convergence characteristics of the research projects are represented by inherent attributes of technology and behavioral attributes of actors. The measuring process of the proxy variables (Rao-Stirling and Herfindahl-Hirschman Indices) for each attributes are proposed. These two indices are used to construct the convergence diagram, through which the research projects of GRIs are distributed into four areas: AllianceIntra, Alliance-Inter, Competition, Mission-Oriented. Based on the convergence diagram proposed in this study the convergence index is measured to derive 30 convergence research areas of GRIs. As a result, we expect to provide appropriate guidelines for setting the policy direction of the convergence research projects.

Psychometrics of a Korean intergenerational psychological ambivalence scale for young adult children (한국판 세대 간 심리적 양가성 척도 타당화: 청년자녀를 중심으로)

  • Lee, Jeenkyoung;Lee, Jaerim
    • Journal of Family Relations
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    • v.23 no.3
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    • pp.105-130
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    • 2018
  • Objective: In this study, we examined the psychometric properties of the Korean Intergenerational Psychological Ambivalence Scale (KIPAS) for young adult children. Method: Data came from 1,140 Korean young adults aged 19-34, who were never married and had at least one living parent. We translated the individual-subjective dimension of Zygowicz's (2006) Intergenerational Ambivalence Scale from English to Korean. The individual-subjective dimension had eight items that directly measured intergenerational psychological ambivalence (D-KIPAS) and 10 items that indirectly measured intergenerational psychological ambivalence (I-KIPAS). Results: The D-KIPAS and I-KIPAS items showed good internal consistency both for the mother and the father. Confirmatory factor analysis showed that D-KIPAS items loaded on one factor after controlling for method effects, which allowed error variances among the four non-reversed items to covary. Both the positive and negative items of I-KIPAS had good reliability and loaded on the same factor. The mean score of D-KIPAS and the calculated score of I-KIPAS were significantly but moderately correlated, which indicates that the D-KIPAS and I-KIPAS assess correlated but distinct aspects of intergenerational ambivalence. Correlations among D-KIPAS, I-KIPAS, and the proxy variables of intergenerational solidarity and conflict supported the discriminant validity of the KIPAS. Conclusion: The results of this study suggest that both D-KIPAS and I-KIPAS are reliable and valid tools to measure intergenerational psychological ambivalence among Korean young adults.

The Effect of Firm's Internationalization on Accounting Earnings Persistence (기업의 국제화가 회계이익의 지속성에 미치는 효과 분석)

  • Choi, Yu-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.1
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    • pp.221-230
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    • 2021
  • In this study, a firm's internationalization level was measured as the ratio of foreign sales to total sales (FSTS) of individual firms. A demonstration was conducted with several control variables that affect the persistence of the firm's profits using the Sloan (1996) model as a proxy for its primary relationship between net profit and the next profit. An empirical analysis of the end-December settlement firms listed on the securities market from 2011 to 2016 was conducted using a fixed-effect model to confirm that the persistence of the firm's internationalization and accounting profits was positive at the 1% significant level, indicating that the persistence of the firm's profits also increased as the level of individual firm's internationalization increased. In addition, the firm size, financial soundness, cash accompanying, growth, and investment ability, consistent with forecasts, represented a statistically significant (+) relationship with globalization. These results suggest that firms can maintain and expand their value stably by securing new overseas markets and promoting growth by implementing internationalization strategies.

Mapping Poverty Distribution of Urban Area using VIIRS Nighttime Light Satellite Imageries in D.I Yogyakarta, Indonesia

  • KHAIRUNNISAH;Arie Wahyu WIJAYANTO;Setia, PRAMANA
    • Asian Journal of Business Environment
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    • v.13 no.2
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    • pp.9-20
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    • 2023
  • Purpose: This study aims to map the spatial distribution of poverty using nighttime light satellite images as a proxy indicator of economic activities and infrastructure distribution in D.I Yogyakarta, Indonesia. Research design, data, and methodology: This study uses official poverty statistics (National Socio-economic Survey (SUSENAS) and Poverty Database 2015) to compare satellite imagery's ability to identify poor urban areas in D.I Yogyakarta. National Socioeconomic Survey (SUSENAS), as poverty statistics at the macro level, uses expenditure to determine the poor in a region. Poverty Database 2015 (BDT 2015), as poverty statistics at the micro-level, uses asset ownership to determine the poor population in an area. Pearson correlation is used to identify the correlation among variables and construct a Support Vector Regression (SVR) model to estimate the poverty level at a granular level of 1 km x 1 km. Results: It is found that macro poverty level and moderate annual nighttime light intensity have a Pearson correlation of 74 percent. It is more significant than micro poverty, with the Pearson correlation being 49 percent in 2015. The SVR prediction model can achieve the root mean squared error (RMSE) of up to 8.48 percent on SUSENAS 2020 poverty data.Conclusion: Nighttime light satellite imagery data has potential benefits as alternative data to support regional poverty mapping, especially in urban areas. Using satellite imagery data is better at predicting regional poverty based on expenditure than asset ownership at the micro-level. Light intensity at night can better describe the use of electricity consumption for economic activities at night, which is captured in spending on electricity financing compared to asset ownership.

Foreign Equity Ownership and Investors' Heterogeneous Beliefs (외국인지분율과 투자자들 간의 상이한 믿음)

  • Byun, Sun-Young;Jung, Hyun-Uk
    • Korea Trade Review
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    • v.42 no.2
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    • pp.227-249
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    • 2017
  • This study investigates whether foreign equity ownership is associated with trading volume. This study establishes null hypothesis indicating that foreign equity ownership is not related to trading volume based on prior studies regarding foreign equity ownership. We measured trading volume as proxy of investors' heterogeneous beliefs. To exam The the hypothesis, we collected sample firms listed on the Korean Stock Exchange from the year of 2001 to the year of 2011 inclusively. Controlling for variables related with trading volume as reported in the previous studies, the regression coefficient for the foreign equity ownership showed statistically significant negative sign. These results indicate that the foreign equity ownership is negatively associated with investors' heterogeneous beliefs. This study contributes to extant literature on foreign equity ownership by providing evidence that foreign equity ownership affects investors' trading decisions. The results also help policy makers in their policy development.

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