Elevated red cell distribution width is associated with advanced fibrosis in NAFLD

Background/AimsThe red-blood-cell distribution width (RDW) is a newly recognized risk marker in patients with cardiovascular disease, but its role in nonalcoholic fatty liver disease (NAFLD) has not been well defined. The aim of the present study was to determine the association between RDW values and the level of fibrosis in NAFLD according to BARD and FIB-4 scores.MethodsThis study included 24,547 subjects who had been diagnosed with NAFLD based on abdominal ultrasonography and questionnaires about alcohol consumption. The degree of liver fibrosis was determined according to BARD and FIB-4 scores. The association between RDW values and the degree of fibrosis in NAFLD was analyzed retrospectively.ResultsAfter adjusting for age, hemoglobin level, mean corpuscular volume, history of hypertension, history of diabetes, and high-sensitivity C-reactive protein, the RDW values were 12.61±0.41% (mean±SD), 12.70±0.70%, 12.77±0.62%, 12.87±0.82%, and 13.25±0.90% for those with BARD scores of 0, 1, 2, 3, and 4, respectively, and 12.71±0.72%, 12.79±0.66%, and 13.23±1.52% for those with FIB-4 scores of <1.30, 1.31-2.66, and ≥2.67, respectively (P<0.05). The prevalence of advanced fibrosis (BARD score of 24 and FIB-4 score of ≥1.3) increased with the RDW [BARD score: 51.1% in quartile 1 (Q1) vs. 63.6% in Q4; FIB-4 score: 6.9% in Q1 vs. 10.5% in Q4; P<0.001]. After adjustments, the odds ratio of having advanced fibrosis for those in Q4 compared to Q1 were 1.76 (95%CI=1.55-2.00, P<0.001) relative to BARD score and 1.69 (95%CI=1.52-1.98, P<0.001) relative to FIB-4 score.ConclusionsElevated RDW is independently associated with advanced fibrosis in NAFLD

Essays in semiparametric and nonparametric estimation with application to growth accounting

This dissertation develops efficient semiparametric estimation of parameters and expectations in dynamic nonlinear systems and analyzes the role of environmental factors in productivity growth accounting. The first essay considers the estimation of a general class of dynamic nonlinear systems. The semiparametric efficiency bound and efficient score are established for the problems. Using an M-estimator based on the efficient score, the feasible form of the semiparametric efficient estimators is worked out for several explicit assumptions regarding the degree of dependence between the predetermined variables and the disturbances of the model. Using this result, the second essay develops semiparametric estimation of the expectation of known functions of observable variables and unknown parameters in the class of dynamic nonlinear models. The semiparametric efficiency bound for this problem is established and an estimator that achieves the bound is worked out for two explicit assumptions. For the assumption of independence, the residual-based predictors proposed by Brown and Mariano (1989) are shown to be semiparametric efficient. Under unconditional mean zero assumption, I proposed an improved heteroskedastic autocorrelation consistent estimator. The third essay explores the directional distance function method to analyze productivity growth. The method explicitly evaluates the role of undesirable outputs of the economy, such as carbon dioxide and other green-house gases, have on the frontier production process which we specify as a piecewise linear and convex boundary function. We decompose productivity growth into efficiency change (catching up) and technology change (innovation). We test the statistical significance of the estimates using recently developed bootstrap method. We also explore implications for growth of total factor productivity in the OECD and Asia economies

Fight against underground economy

노트 : This paper is prepared for KWE 12th conference at Tehran (Isfahan) from June 25 to June 27, 2013. The paper is the summary of the research sponsored by KDI(2010). 페이지

(2010) 경제발전경험모듈화사업: 조세정책

The Korean government has been striving to enhance transparency in all commercial transactions with the objective of achieving equity within the context of taxation. One of the keys to accomplishing such an objective is the use of an income tax deduction scheme calculated using receipts from credit card and cash transactions. Under this scheme, if a taxpayer made a payment via credit card and/or cash, that individual would be entitled to a tax deduction of a prescribed percentage of the purchased amount from their taxable income base. This scheme aims to encourage the taxpayers to actively use credit cards and cash receipts, which allow the disclosure of their transaction history to a third party, in the course of their economic activities. The ultimate goal of this scheme is to enhance transparency of income derived by businesses which provide a product or service directly to the end users. The government has been making great efforts to attain success in the operation of the credit card and cash receipts income deduction scheme, which focuses on two major strategies. Firstly, this scheme strives to establish a solid foundation supportive of the active use of credit cards and cash receipts. Even prior to the introduction of the scheme, the government devoted its energies to encourage the users to actively participate. At the launch of the scheme, the government made the scheme mandatory for the businesses of a prescribed size while pursuing the acceptance from the public with tax-based policies and various sub-mechanisms to suit different types of businesses. The outcomes of these two strategies provided the basis for other businesses to adopt the use of receipts for both the credit card and cash in the commercial transactions. The other strategy concerns with the enhancement of the public’s acceptance of the scheme by combining various policies and strategies related thereto. In addition to the incentives provided to the buyers, tax reduction was offered to the suppliers to offset the increased transaction costs and tax burden. The lottery programs simultaneously operated for those who find it difficult to meet the minimum consumption requirement (i.e. at least 10% of their total salary), preset on the expense point of view, promoted more participation in general. In addition, to prevent intentional avoidance of the scheme, the government has implemented various administrative sanctions to strengthen compliance by taxpayers including the ‘additional tax penalty program’ and the ‘reporter rewards program’. Therefore, so as to newly introduce this income deduction scheme, taking into account the two aforementioned factors, it is necessary to expand the infrastructure required in utilizing the major payment methods both before and after the implementation. In addition, appropriate economic incentives for both transaction parties in conjunction with administrative sanctions against the violators are also required. Another consideration in introducing the scheme relates to the opportunity to create supplementary schemes to enable more taxpayers to use the scheme.Chapter 01 The Credit Card and Cash Receipts Income Deduction Scheme Summary 14 1. Background of the Scheme 15 2. Description of the Scheme 19 3. Scheme Promotion Procedures 49 4. Evaluations 53 5. Policy Recommendations 59 References 61 Chapter 02 Experience of Earmarked Taxation for Development Resource Summary 64 1. Background for Introduction 65 2. Details 79 3. Implementation Methods 102 4. Assessment and Implications 105 References 11

Distributional effect of taxes and benefits in Korea

A Simulation model has been developed in Korea, named Korea Institute of Public Finance Simulation Model (KIPFSIM), which aims to estimate the effects of taxes and transfers in Korea. The current version of KIPFSIM adopts a statice approach combined with a zero-elasticity assumption that there will be no change in labor supply and consumption decisions even after changes in taxes and transfers. KIPFSIM uses a representative sample from the House-hold Income and Expenditure Survey, compiled and released by the Statistical Office of Korea. Using KIPFSIM, we hypothetical changes in taxes and transfers, which is set to be enacted in 2009 and 2010. We found that the benefit of the income tax cut is concentrated mostly on high-income taxpayers in terms of absolute value, but more on middle-income taxpayers in terms of percentage of the tax burden. Therefore, the new income tax law is considered to strengthen the progressive nature of the tax code and to lower tax burdens and tax revenue. We also found that after-income-tax income inequality, as measured by Gini coefficeint, was slightly worsened, primarily due to the decrease in income tax revenue, whice helps equalize income distribution