The frequency of visiting a doctor: Is the decision to go independent of the frequency?

In his analysis of the effects of the reform of the German healthcare system, Winkelmann (Journal of Applied Econometrics 2004; 19 : 455–472) investigates the number of doctor visits. He makes a distinction between the decision to go to a physician and the number of times the physician is visited in the observed time period. Winkelmann finds that there is no correlation between both decisions. This result appears to be far from straightforward since the primary driving force in both decisions will be the health of the patient. From this perspective a significant correlation is expected. In this paper, I first replicate part of Winkelmann's research. I then set out to analyse whether the zero correlation is actually true or comes from the way the relation between both decisions is modelled. My empirical analysis confirms the latter, but nevertheless also corroborates Winkelmann's main conclusions on the relevance of the explanatory variables used in his investigation. Copyright © 2011 John Wiley & Sons, Ltd.     

SEMI-PARAMETRIC ESTIMATION OF HURDLE REGRESSION MODELS WITH AN APPLICATION TO MEDICAID UTILIZATION

This paper develops a semi-parametric estimation method for hurdle (two-part) count regression models. The approach in each stage is based on Laguerre series expansion for the unknown density of the unobserved heterogeneity. The semi-parametric hurdle model nests Poisson and negative binomial hurdle models, which have been used in recent applied literature. The empirical part of the paper evaluates the impact of managed care programmes for Medicaid eligibles on utilization of health-care services using a key utilization variable, the number of doctor and health centre visits. Health status measures and age seem to be more important in determining health-care utilization than other socio-economic and enrollment variables. The semi-parametric approach is particularly useful for the analysis of overdispersed individual level data characterized by a large proportion of non-users, and highly skewed distribution of counts for users. © 1997 John Wiley & Sons, Ltd.     

Estimation in a generalization of bivariate probit models with dummy endogenous regressors

The purpose of this paper is to provide guidelines for empirical researchers who use a class of bivariate threshold crossing models with dummy endogenous variables. A common practice employed by the researchers is the specification of the joint distribution of unobservables as a bivariate normal distribution, which results in a bivariate probit model. To address the problem of misspecification in this practice, we propose an easy‐to‐implement semiparametric estimation framework with parametric copula and nonparametric marginal distributions. We establish asymptotic theory, including root‐n normality, for the sieve maximum likelihood estimators that can be used to conduct inference on the individual structural parameters and the average treatment effect (ATE). In order to show the practical relevance of the proposed framework, we conduct a sensitivity analysis via extensive Monte Carlo simulation exercises. The results suggest that estimates of the parameters, especially the ATE, are sensitive to parametric specification, while semiparametric estimation exhibits robustness to underlying data‐generating processes. We then provide an empirical illustration where we estimate the effect of health insurance on doctor visits. In this paper, we also show that the absence of excluded instruments may result in identification failure, in contrast to what some practitioners believe.     

Repeat tourism in Uruguay: modelling truncated distributions of count data

This paper studies the determinants of repeat visiting in Uruguay, where loyal visitors are a relevant part of the total. From a statistical point of view, the number of times a visitor has been to a place constitutes count data. In this regard available information on Uruguay presents relevant limitations. Count data is in fact reported only for those who visited the country up to five times, whereas records about the most frequent visitors are collapsed into one residual category. This implies that the classic models for count data such as Poisson or negative binomial cannot be put into consideration. The paper suggests instead modelling the available part of the empirical distribution through quantile count data regression. It is a model based on measures of location rather than mean values, which allows estimating tourists’ behaviour as the number of visits increases. A set of explanatory variables related to budgetary constraints, socioeconomic, trip-related and psychographic characteristics are taken as regressors to the considered count data.     

Work absences and doctor visits during an illness episode: The differential role of preferences,production, and policies among men and women

This paper analyzes the absenteeism and medical care consumption behavior of employed men and women during an episode of acute illness. An individual’s daily optimization decisions are modeled in a dynamic framework to evaluate the role of (1) preferences for absences and treatment, (2) effectiveness of these inputs on recovery, and (3) economic incentives in determining the number and timing of absences and doctor visits and the duration of illness. In general, men appear to be more responsive than women to changes in sick leave and health insurance mainly due to differences in preferences.     

Multiple Visits and Data Quality in Household Surveys

In order to increase data quality some household surveys visit the respondent households several times to estimate one measure of consumption. For example, in Ghanaian Living Standards Measurement surveys, households are visited up to 10 times over a period of 1 month. I find strong evidence for conditioning effects as a result of this approach: In the Ghanaian data the estimated level of consumption is a function of the number of prior visits, with consumption being highest in the earlier survey visits. Telescoping (perceiving events as being more recent than they are) or seasonality (first‐of‐the‐month effects) cannot explain the observed pattern. To study whether earlier or later survey visits are of higher quality, I employ a strategy based on Benford's law. Results suggest that the consumption data from earlier survey visits are of higher quality than data from later visits. The findings have implications for the value of additional visits in household surveys, and also shed light on possible measurement problems in high‐frequency panels. They add to a recent literature on measurement errors in consumption surveys (Beegle et al., 2012 , Gibson et al., 2015 ), and complement findings by Zwane et al. ( 2011 ) regarding the effect of surveys on subsequent behaviour.     

Incentive effects in the demand for health care: a bivariate panel count data estimation

This paper contributes in three dimensions to the literature on health care demand. First, it features the first application of a bivariate random effects estimator in a count data setting, to permit the efficient estimation of this type of model with panel data. Second, it provides an innovative test of adverse selection and confirms that high‐risk individuals are more likely to acquire supplemental add‐on insurance. Third, the estimations yield that in accordance with the theory of moral hazard, we observe a much lower frequency of doctor visits among the self‐employed, and among mothers of small children. Copyright © 2002 John Wiley & Sons, Ltd.     

Validity of Medicaid household respondent reporting of ambulatory visits for mental disorders.

Comparison with administrative records or "best estimate file" enables an evaluation of the accuracy of household reports of mental health use in the four-State Medicaid Household Survey conducted as part of the National Medical Care Utilization and Expenditure Survey. Underreporting of probability of ambulatory mental health use ranged from 14 to 24% compared to 5 to 7% for ambulatory health visits; household estimates of number of mental health visits seemed to be more accurate than administrative records. Household reporting of provider type seemed to be very accurate for psychiatrist visits, but there seemed to be a tendency to report psychologist visits as psychiatrist visits.     

The German model in danger

The German high‐skills/high value‐added economy has long been the Mecca for supporters of the European social model. So long as Model Deutschland was thriving the notion of Social Europe was a plausible political project. But Germany is facing a range of economic problems—the aftershock of reunification, high unemployment and internal and external pressures to reform its stakeholder system of economic organisation. Some of these developments strike at core assumptions of the German model. This article reviews the extent to which the German model is in danger and teases out the implications for the wider European economy.     

德国职业教育对中国职业教育改革的启示

我国已经将职业教育改革提高到战略的高度,并取得了一定的成果,但仍需进一步深化。德国职业教育的成功得到广泛认可,根据国情,将德国职业教育引进来,中国化,是非常有益的。本文从四个方面对德国职业教育介绍,结合我国现阶段职业教育的情况,提出了职业教育改革应从改变教育理念,组建优秀的教师团队,形成符合自身的、系统的教学方法,改革现行的考核制度等方面着手。对中国职业教育改革有启示作用和借鉴意义。     

Selection correction and sensitivity analysis for ordered treatment effect on count response

In estimating the effect of an ordered treatment τ on a count response y with an observational data where τ is self‐selected (not randomized), observed variables x and unobserved variables ε can be unbalanced across the control group (τ = 0) and the treatment groups (τ = 1, …, J). While the imbalance in x causes ‘overt bias’ which can be removed by controlling for x, the imbalance in ε causes ‘covert (hidden or selection) bias’ which cannot be easily removed. This paper makes three contributions. First, a proper counter‐factual causal framework for ordered treatment effect on count response is set up. Second, with no plausible instrument available for τ, a selection correction approach is proposed for the hidden bias. Third, a nonparametric sensitivity analysis is proposed where the treatment effect is nonparametrically estimated under no hidden bias first, and then a sensitivity analysis is conducted to see how sensitive the nonparametric estimate is to the assumption of no hidden bias. The analytic framework is applied to data from the Health and Retirement Study: the treatment is ordered exercise levels in five categories and the response is doctor office visits per year. The selection correction approach yields very large effects, which are however ruled out by the nonparametric sensitivity analysis. This finding suggests a good deal of caution in using selection correction approaches. Copyright © 2004 John Wiley & Sons, Ltd.     

Explaining differences in labour market transitions between panel and life-course data in West-Germany

Panel and life-course data are ideally suited to unravelling labour market dynamics, but their designs differ, with potential consequences for the estimated relationships. To gauge the extent to which these two data designs produce dissimilar transition rates and the causation thereof, we use the German Life History Study and the German Socio-Economic Panel. Life-course data in particular suffer from recall effects due to memory bias causing understated transition probabilities. Panel data suffer from seam effects due to spurious transitions between statuses recalled in activity calendars that generate heaps at particular time points and cause overstated transition probabilities. We combine the two datasets and estimate multilevel (multistate) discrete-time models for event history data to model transitions between labour market states taking these factors into account. Though we find much lower transition rates in the life-course study, confirming the results of Solga (Qual Quant 35:291–309, 2001) in this Journal for East-Germany, part of the difference can be explained by short spells recall bias. The estimated models on exit, re-entry and job mobility on the combined datasets show indeed a negative retrospective design effect. Another specification that includes the length of the recall period shows no significant decrease in the transition probabilities with increasing length, suggesting that the negative design effect is due to other design differences.     

Spell durations with long unemployment insurance periods

This paper uses data from a natural experiment to investigate the potential incentive effect of a fixed unemployment insurance period. We compare two large groups of Norwegian unemployed persons who registered as unemployed in 1990 and 1991. The last group was affected by a rule change that in practice extended the length of unemployment benefits to more than 3 years. Our data are taken from official records, and we construct unemployment durations by combining information from the unemployment registers with employers' records. We use a proportional hazard model with a flexible baseline. The results suggest that the main effect of benefits running out is to make people drop out of the unemployment register. We find neither clear evidence that the hazard into employment increased when the end of benefits approached in the pre-liberalisation group, nor that behaviour in this part of the spells changed after the reform. On the other hand, our results suggest that the reform had an all over negative effect on the employment hazard.     

关于德国铁路货运公司收购斯廷思股份公司(Stinnes AG)的思考

结合对德国铁路改革的考察，着重对德国铁路货运改革进行了分析，阐述了德国铁路货运向物流业转变的过程、意义等，由此提出了我国铁路货运向“中铁物流”转型的相关思路。     

The German model of industrial relations at the crossroads: past,present and future

This article examines the pressures for reform in the German model of industrial relations, with particular emphasis on the sectoral bargaining system. It assesses if, how and to what extent the German model with its proven track record should be reformed. The article advocates a reform path within the parameters of the excisting system in order to strike subtle balance between stability and change.     

德法模式政府会计改革动因的比较与启示

本文旨在通过对德法模式的政府会计改革动因进行研究,力图总结德法模式政府会计改革动因的基本脉络,希望对我国政府会计改革有所启示。通过分析,我们理清了德法模式政府会计改革动因的基本脉络,并归纳出具有代表性的具体改革动因。通过考察我国政府会计改革的潜在动因,我们认为我国进行政府会计改革是大势所趋的选择。     

Why are the unemployed in worse health? The causal effect of unemployment on health

We analyse the effect of unemployment on health using information from the German Socio-Economic Panel of the years 1991-2008. To establish a causal effect we rely on fixed-effects methods and plant closures as exogenous entries into unemployment. Although unemployment is negatively correlated with health, we do not find a negative effect of unemployment due to plant closure on health across several health measures (health satisfaction, mental health, and hospital visits). For this subgroup of the unemployed, unemployment does not seem to be harmful and selection effects of ill individuals into unemployment are likely to contribute to the observed overall correlation between poor health and unemployment.     

中国医疗卫生事业效益分析之系列研究——2000～2010年上海市医疗卫生机构效益分析

目的:研究中国最大城市之一的上海市医疗卫生行业投入与产出效益情况并找出影响因素并提出对策。方法:收集2000年-2010年相关数据,采用平均增长量、平均发展速度、平均增长速度计算出投入、产出指标值。结果:11年间上海市医疗卫生机构规模缩小。人员和病床规模扩大,但速度不及人口发展速度快,诊疗人数年均增长9.3%,医生人均每日担负诊疗人次年均增长速度达6.63%。人均住院费用年均增长6.04%,其中药费年均7.32%。结论:加大投入人力物力,合理医药改革,建立健全三级医疗体系,健全医疗保障制度,完善社会保障体系,保证医疗行业的公益性,充分发挥其社会职能。     

Henry George and Europe:

A bstract Henry George's Progress and Poverty was translated into German and published in Germany in 1881, a little more than a year after its publication in America But it was not through George's own words that his ideas first became known there Germany already had land reformers , organized in small societies They made his teachings known However, unlike the case in Britain, Germany's leftists did not welcome George's land reform ideas True, Karl Marx recognized and wrote about the role the land question played in the exploitation of labor and in his third volume of Capital took basic positions parallel to George's, it was published long after Progress and Poverty The hostility of Wilhelm Ltebknecbt toward land reform reflected the German public's disinterest in the land question and may explain why Marx concentrated on appealing to the urban industrial worker