• Title/Summary/Keyword: proxy variables

Search Result 125, Processing Time 0.023 seconds

Analysis of Climate Characteristics Observed over the Korean Peninsula for the Estimation of Climate Change Vulnerability Index (기후변화 취약성 지수 산출을 위한 한반도 관측 기후 특성 분석)

  • Nam, Ki-Pyo;Kang, Jeong-Eon;Kim, Cheol-Hee
    • Journal of Environmental Impact Assessment
    • /
    • v.20 no.6
    • /
    • pp.891-905
    • /
    • 2011
  • Climate vulnerability index is usually defined as a function of the climate exposure, sensitivity, and adaptive capacity, which requires adequate selection of proxy variables of each variable. We selected and used 9 proxy variables related to climate exposure in the literature, and diagnosed the adequacy of them for application in Korean peninsula. The selected proxy variables are: four variables from temperature, three from precipitation, one from wind speed, and one from relative humidity. We collected climate data over both previous year (1981~2010) and future climate scenario (A1B scenario of IPCC SERES) for 2020, 2050, and 2100. We introduced the spatial and temporal diagnostic statistical parameters, and evaluated both spatial and time variabilities in the relative scale. Of 9 proxy variables, effective humidity indicated the most sensitive to climate change temporally with the biggest spatial variability, implying a good proxy variable in diagnostics of climate change vulnerability in Korea. The second most sensitive variable is the frequency of strong wind speed with a decreasing trend, suggesting that it should be used carefully or may not be of broad utility as a proxy variable in Korea. The A1B scenario of future climate in 2020, 2050 and 2100 matches well with the extension of linear trend of observed variables during 1981~2010, indicating that, except for strong wind speed, the selected proxy variables can be effectively used in calculating the vulnerability index for both past and future climate over Korea. Other local variabilities for the past and future climate in association with climate exposure variables are also discussed here.

Vulnerability Assessment of Water Quality and Aquatic Ecosystem to Climate Change in Korea using Proxy Variables (대리변수를 이용한 한반도 수질 및 수생태계 부문의 기후변화 취약성 평가)

  • Lee, Keon Haeng;Chung, Eu Gene;Kim, Kyunghyun;Yu, Jeong Ah;Lee, Eun Jeong
    • Journal of Korean Society on Water Environment
    • /
    • v.28 no.3
    • /
    • pp.444-452
    • /
    • 2012
  • This study aims at assessing vulnerability of water quality and aquatic ecosystem to climate change by using proxy variables. Vulnerability to climate change is defined as a function of exposure to climate, sensitivity, and adaptive capacity. Detailed proxy variables were selected considering availability and then standardized by re-scaling concept. After adequate weights were assigned to standardized proxy variables by Delphi technique, vulnerability index was calculated. As results, vulnerability of adjacent regions to coastal areas include water quality and aquatic ecosystem is relatively higher than that of inland areas, and especially adjacent region to the western and southeast seas, and Jeju show high vulnerabilities. Vulnerability in the future was performed based on A1B scenario (IPCC, 2000). Temporally, the increase of vulnerability from 2050s to 2100s may be larger than the increase from 2000s to 2050s. Because vulnerability index was estimated through the relationship among various proxy variables, it is important to consider characteristics of local region with measurements and policies for reduction of sensitivity and enhancement of adaptive capacity on climate change. This study is expected to be useful in planning adaptation measures and selecting priority to the policy on climate change.

A Study on the Vulnerability Assessment for Agricultural Infrastructure using Principal Component Analysis (주성분 분석을 이용한 농업생산기반의 재해 취약성 평가에 관한 연구)

  • Kim, Sung Jae;Kim, Sung Min;Kim, Sang Min
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.55 no.1
    • /
    • pp.31-38
    • /
    • 2013
  • The purpose of this study was to evaluate climate change vulnerability over the agricultural infrastructure in terms of flood and drought using principal component analysis. Vulnerability was assessed using vulnerability resilience index (VRI) which combines climate exposure, sensitivity, and adaptive capacity. Ten flood proxy variables and six drought proxy variables for the vulnerability assessment were selected by opinions of researchers and experts. The statistical data on 16 proxy variables for the local governments (Si, Do) were collected. To identify major variables and to explain the trend in whole data set, principal component analysis (PCA) was conducted. The result of PCA showed that the first 3 principal components explained approximately 83 % and 89 % of the total variance for the flood and drought, respectively. VRI assessment for the local governments based on the PCA results indicated that provinces where having the relatively large cultivation areas were categorized as vulnerable to climate change.

Non-Controlling Interests and Proxy of Real Activities Manipulation in Stakeholder-Oriented Corporate Governance

  • FUJITA, Kento;YAMADA, Akihiro
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.9 no.10
    • /
    • pp.105-113
    • /
    • 2022
  • The purpose of this paper is to analyze the relationship between the ratio of non-controlling shareholder interests (minority equity ratio, MER) and the measurement error in real activities manipulation (RM) proxy for Japanese firms. Many Japanese firms have practiced stakeholder-oriented corporate governance systems. Previous studies suggest that the higher the MER, the more Japanese businesses tend to employ management techniques for the group's sales growth while also reallocating resources inside the group to reduce principal-principal conflicts. Such differences in management strategies by firms could lead to measurement error in the RM proxy. The analysis uses 16,450 firm-years listed on the Tokyo Stock Exchange. The results of our analysis show that there is a positive relationship between MER and the RM proxy, and high persistence of RM proxies, suggesting that the RM proxies may contain measurement error. We also find that MER is correlated with variables associated with management strategy and that controlling for these variables can reduce the measurement error of RM proxy in firms with large MER. This study extends previous research on measurement error in RM proxy by relating them to ownership structure and corporate governance. This paper would contribute to researchers examining issues related to RM.

상태공간모형을 이용한 이자율 확률과정의 추정

  • 전덕빈;정우철
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 2003.11a
    • /
    • pp.11-14
    • /
    • 2003
  • The dynamics of unobservable short rate are frequently estimated directly by using a proxy. We estimate the biases resulting from this practice ("proxy problem"). To solve this problem, State-Space models have been proposed by many researchers. State-Space models have been used to estimate the unobservable variables from the observable variables in econometrics. However, applications of State-Space models often result in a misleading interpretation of the underlying processes especially when the absorbability of the State-Space model and the assumption of noise processes in the state vector are not properly considered. In this study, we propose the exact State-Space model that properly considers the faults of previous researchers to solve the proxy problem.

  • PDF

Effects of Poverty Status on Socio-Emotional Development in Childhood : Focused on Comparing the Effects of Proxy Variables and Poverty-Co-Factors (빈곤지위가 아동의 사회·정서발달에 미치는 영향 :빈곤대리변수와 빈곤동반 위험요소와의 비교를 중심으로)

  • Park, Hyun-sun
    • Journal of the Korean Society of Child Welfare
    • /
    • no.26
    • /
    • pp.113-137
    • /
    • 2008
  • Present study investigated the effects of poverty and poverty-co-factors in childhood. The effect of poverty status was measured by needs-income ratio. It compared its effect on children's socio-emotional development with that of poverty proxy variables such as recipient of public assistance, financial stress, subjective perception about social class, residence in public housing. It also examined the effects of poverty-co-factors after poverty status were controlled. Results show that poverty status has a more consistent negative relationship with socio-emotional development than other proxy variables. However, the relationship between them disappeared after poverty-co-factors were controlled. Findings from the present study suggest that targeted efforts for decreasing poverty-co-factor risks should be made along with financial support.

Stock Price Predictability of Financial Ratios and Macroeconomic Variables: A Regulatory Perspective

  • Kwag, Seung Woog;Kim, Yong Seog
    • Industrial Engineering and Management Systems
    • /
    • v.12 no.4
    • /
    • pp.406-415
    • /
    • 2013
  • The present study examines a set of financial ratios in predicting the up or down movements of stock prices in the context of a securities law, the Sarbanes-Oxley Act of 2002 (SOA), controlling for macroeconomic variables. Using the logistic regression with proxy betas to alleviate the incompatibility problem between the firm-specific financial ratios and macroeconomic indicators, we report evidence that financial ratios are meaningful predictors of stock price changes, which subdue the influence of macroeconomic indicators on stock returns, and more importantly that the SOA truly improves the stock price predictability of financial ratios for the markup sample. The empirical results further suggest that industry and time effects exist and that for the markdown sample the SOA actually deteriorates the predictive power of financial ratios.

A Simultaneous Analysis on the Relationship Between Household Productivity and Market Productivity (가정생산성과 시장생산성의 관계분석을 통한 경제위기 대응력 증진을 위한 연구)

  • 정순희;최혜경
    • Journal of Families and Better Life
    • /
    • v.18 no.2
    • /
    • pp.45-60
    • /
    • 2000
  • The purpose of this study was to examine the relationship between household productivity and market productivity of the married men in their early adulthood. Proxy variables of the household productivity were housework time, family cohesion·adaptability and family economic resource. Also proxy variables of the market productivity were job performance, job satisfaction and wage. The main result were as follows: First, men's housework time is insignificantly related to men's job performance, job satisfaction, and wage. But men's housework time is reduced as men's wage. Second, family cohesion·adaptability is significantly and positively related to the married men's job performance. The married men's job performance is significantly and positively related to the family cohesion·adaptability.

  • PDF

Priority survey between indicators and analytic hierarchy process analysis for green chemistry technology assessment

  • Kim, Sungjune;Hong, Seokpyo;Ahn, Kilsoo;Gong, Sungyong
    • Environmental Analysis Health and Toxicology
    • /
    • v.30 no.sup
    • /
    • pp.3.1-3.11
    • /
    • 2015
  • Objectives This study presents the indicators and proxy variables for the quantitative assessment of green chemistry technologies and evaluates the relative importance of each assessment element by consulting experts from the fields of ecology, chemistry, safety, and public health. Methods The results collected were subjected to an analytic hierarchy process to obtain the weights of the indicators and the proxy variables. Results These weights may prove useful in avoiding having to resort to qualitative means in absence of weights between indicators when integrating the results of quantitative assessment by indicator. Conclusions This study points to the limitations of current quantitative assessment techniques for green chemistry technologies and seeks to present the future direction for quantitative assessment of green chemistry technologies.

Determinants of Rural Tourism Demand (농촌관광수요의 결정요인)

  • Eun-Ho Son;Jung-Dae Goo
    • Journal of Agricultural Extension & Community Development
    • /
    • v.30 no.1
    • /
    • pp.43-52
    • /
    • 2023
  • This study aims to examine the effects of GDP as a proxy variable of income, consumer price index as a proxy variable of price, and foot-and-mouth disease and avian influenza as derby variables on rural tourism demand. The independent variables in this research were gross domestic product(GDP), consumer price index(CPI), and dummy variable(DM) such as food & mouth disease & highly pathogenic avian influenza. Results showed that GDP affected tourism demand positively whereas DM influenced negatively. The study suggested that it was important for policy-mconsider GDP and DM when making decision on strategic tourism management. In conclusion, first, gross domestic product was found to have a statistically significant effect on rural tourism demand. Second, avian influenza was found to have a statistically negative effect on rural tourism demand. The results of this study can be used to establish a reasonable rural tourism policy in the future economic dimension.