• Korean Journal of Breeding Science
• /
• v.41 no.3
• /
• pp.220-227
• /
• 2009

This study was conducted to select superior families based on the open-pollinated (OP) progeny tests of P. densiflora. A total of 232 OP families were analyzed for relative height growth. The OP progeny test trials were established at 1 to 4 sites from 1975 to 1987. To minimize temporal and spatial variation, we applied the standardization method for family selection. In each progeny test, superior and inferior families were selected at ages of 10, 20 and 30. Relative height growth rate (RHGR), growth speed at a given time unit, was comparatively high at age of 10 with range from 0.1 to 0.6 and showed a large variation among families. However, after age 15, the RHGR was low (average 0.04) and also the variation was not significantly different among families. To reduce selection errors due to age differences (from age 23 to 35) of tests, we made the family selection after age 15 when the values of RHGR were stable. Height growth at each age was transformed to be height growth at age 35 based on the RHGR. As the results, family CB2, CB3, KW99 and KW2 were selected as superior families and KW158, KW22, KB40 and GG1 were considered as inferior ones, respectively. Rank correlations (r) between test ages and selection age 35 were high and statistically significant; r = 0.881 between age 30 and 35, 0.653 between age 20 and 35, and -0.222 between age 10 and 35.

• Korea journal of population studies
• /
• v.29 no.3
• /
• pp.159-188
• /
• 2006

This study attempts to create a longitudinal dataset by linking tdata on the identical individuals across the monthly sample household management lists of the Economically Active Population Survey(EAPS) and the Household Income and Expenditure Survey(HIES). Using the data constructed through such process, the study also tryies to analyze the duration of longitudinal responses and the characteristics of nonrespondents. Between 1998 and 2002, longitudinal response rates had declined to 46% of total EAPS and 34% of total HIES. The fact that nonresponse was not a random phenomenon leads to concerns about the representativeness of the remaining sample. Using Cox's proportional hazard model the study revealed that the duration of longitudinal responses is affected by the ownership of house and the age of the respondent.

• The Journal of the Korea Contents Association
• /
• v.17 no.9
• /
• pp.396-405
• /
• 2017

Main purpose of this study is to analyze determinants of household debt among middle and old individuals aged between 32 and 76 that include Korean baby-boomers(born between 1955 and 1963), using a HAPC (Hierarchical Age-Period-Cohort) model and Korean Welfare Panel Study 2006-2016. This study includes 86,056 individuals. Research findings indicate that aging and period effects have statistically significant relationships with household debt levels, however, cohort effects including a baby-boomer generation do not. While household debt increases by 3,530,000 Korean won as age increases by one year, the rate of increase in household debt reduces as individual ages. In addition, employment and health status at the individual level have significant effects on household debt levels. The unemployed are more likely than the employed to have high household debt levels while unhealthy people tend than healthy people to have high household debt levels.

• Journal of Consumption Culture
• /
• v.15 no.2
• /
• pp.213-247
• /
• 2012

The purpose of this study was to analyze the economic structures of low-income households, and to provide the policy suggestions for their economic well-being. The data for this study was from the 2009 year of the Korea Welfare Panel Survey (KOWEPS). The results are as follows: As for income structure, the low-income households had lower amounts in earned income, business and side-work income, and property income, but a higher amount in transfer income. They had a lower amount in private transfer income, but a higher amount in public transfer income. They had the highest rate of transfer income, showing that the rate of public transfer income was higher than that of private transfer income, and the government assistance was the highest rate in public transfer income. The households in extreme poverty had the lowest amounts in earned income, financial income, private transfer income, but the highest amount in public transfer income. The households in poverty had the lowest amount in transfer income. The households in extreme poverty, poverty and near poverty showed the highest rate in transfer income. As for asset structure, the low-income households had a lower amount in every type of assets. They showed the highest rate in total debt, and had a higher rate in housing asset, but lower rates in real-estate asset, financial asset and other asset. The households in extreme poverty had a lower amount in every type of assets than the households in near poverty. Three types of the low-income households showed the highest rate in housing asset, but the households in extreme poverty was the highest among them. As for expenditure structure, the low-income households had lower amounts in all of the expenditure items. They showed the highest rate in food expenditure, the second highest in other consumption expenditure. The households in extreme poverty showed lower amounts in almost all of the expenditure items than the households in near poverty, but the households in extreme poverty showed a higher amount in monthly rent than the households in neat poverty. Three types of the low-income households showed the highest rate in food expenditure. The expenditure rates of food, monthly rent and light·heat·water for households in extreme poverty were higher than those for the households in near poverty.

• 한국노년학
• /
• v.36 no.3
• /
• pp.809-826
• /
• 2016

This study analyzed private pension dependency of Korea and U.S. households using the most recent dataset of two countries. For this purpose, 2013 Korean Retirement and Income Study(KReIS) of national pension research institute in Korea and 2013 SCF(Survey of Consumer Finances) of FRB in U.S. were used. The private pension dependency was defined as the proportion of private pension wealth among total financial wealth in each household and tobit model was used to investigate determinants of private pension dependency of the two countries. After controlling for other factors, household income and net worth, age, educational attainment, and health status of householder were crucial determinants of private pension dependency for both countries. Householder's age, educational attainment, and health tend to increase the private pension dependency in Korea and U.S. However, household income and net worth affected the private pension dependency opposite direction. The private pension dependency increased with high level of income and net worth in Korea, while it decreased with high level of income and net worth in U.S. Results of this study provide useful implications for future pension system and policy in Korea.

• KDI Journal of Economic Policy
• /
• v.32 no.1
• /
• pp.51-68
• /
• 2010

We use data from the Indonesian Family Life Survey (IFLS) to examine the relationship between child health and household economic resources, and find that economic resources as measured by equivalized expenditure have a statistically significant positive effect on child health and protect children from acute health conditions. We make additional use of the data (where extensive data on children's nutrition, household sanitation, the utilization of medical care, and family health status are available) to assess the mechanisms through which economic resources may affect child health. We find evidence that economic resources have a sizable and significant effect on these potential intermediary factors, and that they, particularly household sanitation, partly explain the protective role of economic resources in child health.

• KDI Journal of Economic Policy
• /
• v.10 no.2
• /
• pp.3-26
• /
• 1988

본(本) 연구(硏究)의 목적(目的)은 우리나라의 1963~86년도 자료를 사용하여 소비(消費) 및 가계저축함수(家計貯蓄函數)를 추정함으로써 가계(家計), 기업(企業), 정부저축(政府貯蓄) 등 세 부문의 저축(貯蓄) 사이에 어떠한 관계, 즉 어느 정도의 대체관계(代替關係)가 있는가를 판별하고 정부저축(政府貯蓄)과 정부재정지출(政府財政支出) 등의 변수(變數)로 표시되는 재정정책(財政政策)의 구축효과(驅逐效果)와 이에 따른 재정정책(財政政策)의 유효성(有效性) 혹은 무력성(無力性) 문제(問題)를 분석하고자 함에 있다. 본(本) 연구(硏究)의 분석결과에 의하면 기업저축(企業貯蓄)과 정부저축(政府貯蓄)은 가계저축(家計貯蓄)과 대체관계(代替關係)가 아닌 보완관계(補完關係)를 갖는 것으로 나타난다. 이는 일국전체(一國全體)의 자본형성(資本形成)에 있어서 기업(企業) 및 정부저축(政府貯蓄)이 매우 중요한 정책변수(政策變數)임을 시사하는 것으로 가계저축율(家計貯蓄率), 나아가 국내저축율(國內貯蓄率)의 제고(提高) 및 유지(維持)를 위해 기업저축증대(企業貯蓄增大)를 위한 제반유인정책(諸般誘因政策)을 꾸준히 강화하고 정부저축증대(政府貯蓄增大)를 위한 효율적이고 건전한 재정운용(財政運用)이 지속되어야 할 것이다. 한편 정부재정지출(政府財政支出)은 적자(赤字)에 의하는 조세(租稅)에 의하든 민간소비(民間消費)를 큰 폭으로 증가시키는 것으로 나타나 가계(家計)의 초합리성가설(初合理性假說)이나 완전(完全)한 선견가설(先見假說)이 상정하는 바와 같이 재정정책(財政政策)의 완전(完全)한 구축효과(驅逐效果)가 나타남에 따른 재정정책(財政政策)의 무력성(無力性) 결과(結果)와 대조적으로 우리나라의 재정정책(財政政策)이 그동안 경제안정(經濟安定)을 위한 강력한 정책수단(政策手段)으로서의 역할을 수행해 왔음을 보여주고 있다.

• The Korean Journal of Applied Statistics
• /
• v.35 no.4
• /
• pp.553-568
• /
• 2022

The Household Income and Expenditure Survey is a representative survey of Statistics Korea, which aims to measure and analyze national income and consumption levels and their changes by understanding the current state of household balances. Recently, the disconnection problem in these time series caused by the large-scale reorganization of the survey methods in 2017 and 2019 has become an issue. In this study, we model the characteristics of the time series in the Household Income and Expenditure Survey up to 2016, and use the modeling to compute forecasts for linking the expenditures in 2017 and 2018. In order to evenly reflect the characteristics across all expenditure item series and to reduce the impact of a specific forecast model, we synthesize a total of 8 models such as regression models, time series models, and machine learning techniques. In particular, the noteworthy aspect of this study is that it improves the forecast by using the optimal combination technique that can exactly reflect the hierarchical structure of the Household Income and Expenditure Survey without loss of information as in the top-down or bottom-up methods. As a result of applying the proposed method to forecast expenditure series from 2017 to 2019, it contributed to the recovery of time series linkage and improved the forecast. In addition, it was confirmed that the hierarchical time series forecasts by the optimal combination method make linkage results closer to the actual survey series.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.7
• /
• pp.183-190
• /
• 2011

Loan amount of housing mortgage is composed of various factors. This study paper studies focuses on estimating the determinants of a loan amount of housing mortgage. The region for analysis consist of seven groups, that is, metropolitan city (such as Busan, Daegu, Incheon, Gwangiu, Daejeon, Ulsan.) and Seoul. Analyzing period be formed over a 45 time points(2007. 01.~ 2010. 09). In this paper the dependent variable setting up loan amount of housing mortgage, explanatory(independent) variables are composed of the consumer price index, unemployment rate, average monthly household income per household, expenditure rate of health care, composite stock price index and overdue rate of household loans for commercial bank. In looking at the factors which determine loan amount of housing mortgage, evidence was produced supporting the hypothesis that there is a significant positive relationship between the consumer price index and unemployment rate. The study also produced evidence supporting the view that there is a significant negative relationship between expenditure rate of health care. The study found that average monthly household income per household, expenditure, composite stock price index and overdue rate of household loans for commercial bank were not significant variables. The implications of these findings are discussed for further research.

• KDI Journal of Economic Policy
• /
• v.28 no.2
• /
• pp.1-49
• /
• 2006

Considering the fact that households' demographic characteristics affect consumption decision, it is conjectured that rapid demographic changes would lead to a substantial change in the composition of private consumption expenditure. This paper estimates the demand functions of various consumption items by applying the Quadratic Almost Ideal Demand System(QUAIDS) model to Household Income and Expenditure Survey data, and then provides a long-term forecast of the composition of household consumption expenditure for 2005-2020. The paper shows that Korea's consumption expenditure will maintain the recent years' rapid change, of which a considerable portion is due to rapid demographic changes. Results of the paper can be utilized in forecasting the change in the industrial structure of the economy, as well as in firms' investment planning.