A duration model based on the time on Unemployment Insurance (UI) benefits instead of a model based on the time till re-employment is more relevant from a cost-benefit perspective. The contribution of this paper is to extend the standard... more
A duration model based on the time on Unemployment Insurance (UI) benefits instead of a model based on the time till re-employment is more relevant from a cost-benefit perspective. The contribution of this paper is to extend the standard (mixed) Proportional Hazard model to account for an upper bound on the duration. We use a modified mover-stayer model to this end and discuss the interpretation of the parameters. In an empirical application we compare the method with the standard analysis of unemployment duration. We also derive the expected UI-benefit costs implied by the model for some typical unemployed individuals.
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An issue hardly ever mentioned in the analysis of labour market transitions is that for some individuals labour market transitions occur at a very low rate. Therefore, these individuals might stay on disability benefits or in domestic... more
An issue hardly ever mentioned in the analysis of labour market transitions is that for some individuals labour market transitions occur at a very low rate. Therefore, these individuals might stay on disability benefits or in domestic care till they reach the retirement age of 65. This implies that the duration on disability and of non-participating women has a upper bound of the time till retirement. Despite the growing availability of panel data on labour market transitions many household surveys are still based on stock based sampling. In this paper estimation of a duration model in which a positive fraction of individuals reaches a maximum duration is derived for stock sampled data. A mixed proportional hazard model with a piecewise constant baseline hazard leads to a relatively simple closed-form expression in the log likelihood. Discrete unobserved heterogeneity is assumed. Non-constant entry rates into the labour market state are allowed for by assuming a yearly fluctuating r...
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We investigate the causal impact of education on life-expectancy using data for England and Wales from the Health and Lifestyles Survey and how that impact is mediated through changes in health behaviour (smoking, exercise, having... more
We investigate the causal impact of education on life-expectancy using data for England and Wales from the Health and Lifestyles Survey and how that impact is mediated through changes in health behaviour (smoking, exercise, having breakfast). For identification of the educational gain in mortality we employ a Regression Discontinuity Design implied by an increase in the minimum school leaving age in 1947 (from 14 to 15) together with a principal stratification method for the mortality hazard rate. This method allows us to derive the direct and indirect (through one or more mediators) effect of education on the implied life-expectancy. Basic maximum likelihood estimation of a standard Gompertz hazard model for the mortality rate suggests that staying in school beyond age 15 years significantly increases life-expectancy by more than 14 years, with large indirect effects running through smoking and exercise. In contrast, estimates from the principal strata method indicate that the educ...
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In this paper, we study the long-term causal effects of the DutchFamine on labor market and healthbehavior later in life (55-70). To acknowledge the dynamic nature oflabor market changes we focus onthe impact of the famine on the timing... more
In this paper, we study the long-term causal effects of the DutchFamine on labor market and healthbehavior later in life (55-70). To acknowledge the dynamic nature oflabor market changes we focus onthe impact of the famine on the timing of becoming disabled or retired.To acknowledge the dynamicnature of health behavior, medication use and health expenditures, we focus on the impact of thefamine on the changes over time of medication use and health expenditures, both categorized. In allanalyses we use a non-linear Difference-in-difference approach to identify the the causal impact offamine exposure in utero on later life outcomes.We account for selective fertility, by restricting our analysis to those conceived before the famine,and for selective survival using either an inverse propensity weighting method or a Copula approach.For the empirical analysis we used data of military recruits born around the Dutch famine (1944-1947) linked to the Dutch mortality register (deaths trough 201...
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Background In 1976, researchers reported that young men are more likely to be obese after famine exposure in utero. The findings were based on examinations at military induction of men in the Netherlands who had been exposed to the Dutch... more
Background In 1976, researchers reported that young men are more likely to be obese after famine exposure in utero. The findings were based on examinations at military induction of men in the Netherlands who had been exposed to the Dutch famine of 1944-1945. We had the opportunity to re-examine the relation between prenatal famine exposure and height and weight at age 18-19 with current definitions for being overweight or obese and with modern analytic methods. Methods and findings We used height and weight information from 408,015 men in the Netherlands born between 1943-1947 and examined for military service at age 18-19. This group includes men with and without prenatal exposure to the Dutch famine of 1944-1945. We found that the odds for being overweight at age 18 were significantly elevated (OR=1.56; CI 1.23 to 1.97) among sons of manual workers born in the famine cities. Contrary to findings in the 1976 publication, no increase was seen among sons of non-manual workers born in...
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Large differences in mortality rates across those with different levels of education are a well-established fact. This association between mortality and education may partly be explained by confounding factors, including intelligence.... more
Large differences in mortality rates across those with different levels of education are a well-established fact. This association between mortality and education may partly be explained by confounding factors, including intelligence. Intelligence may also be affected by education so that it becomes a mediating factor in the causal chain. In this paper we estimate the impact of education on mortality using inverse probability weighted (IPW) estimator, using either intelligence as a selection variable or as a mediating variable. We develop an IPW estimator to analyse the mediating effect in the context of survival models. Our estimates are based on administrative data, on men born in 1944-1947 who were examined for military service in the Netherlands between 1961-1965, linked to national death records. For these men we distinguish four education levels and we make pairwise comparisons. From the empirical analyses we conclude that the mortality differences observed by education are on...
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Background Weight for height has been used in the past as an indicator of obesity to report that prenatal exposure to the Dutch famine of 1944–1945 determined subsequent obesity. Further evaluation is needed as unresolved questions remain... more
Background Weight for height has been used in the past as an indicator of obesity to report that prenatal exposure to the Dutch famine of 1944–1945 determined subsequent obesity. Further evaluation is needed as unresolved questions remain about the possible impact of social class differences in fertility decline during the famine and because being overweight is now defined by a Body Mass Index (BMI: kg/m2) from 25 to <30 and obesity by a BMI of 30 or more. Methods We studied heights and weights of 371,100 men in the Netherlands born between 1943 and 1947 and examined for military service at age 19. This group includes men with and without prenatal exposure to the Dutch famine. Results There was a 1.3-fold increase in the risk of being overweight or obese in young adults at age 19 after prenatal famine exposure in early gestation. The increase was only seen in sons of manual workers born in the large cities of Western Netherlands and not among those born in smaller cities or rural...
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Mental disorders have a large impact on invalidity and mortality. Poor mental health is associated with low education, which is also associated with poor health and higher mortality. The association between mental health and mortality... more
Mental disorders have a large impact on invalidity and mortality. Poor mental health is associated with low education, which is also associated with poor health and higher mortality. The association between mental health and mortality may, therefore, be partly explained by the increased incidence of mental problems of the low educated. An important issue is that mental health problems, education attainment and mortality may all depend on the same observed and unobserved individual factors. We account for both the selective incidence of mental health problems and selective educational attainment by using a correlated multistate model for the mental health (hospitalization) process (both admittance an discharge) and mortality with a re-weighting technique (inverse propensity weighting) based on the probability to attain higher education. We use Swedish Military Conscription Data (1951-1960), linked to the administrative Swedish death and National Hospital Discharge registers. We estim...
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To examine if, over a period of centuries, the Dutch medical establishment enjoyed a survival advantage over a population group with a comparable social background and level of education. Retrospective database research. We used documents... more
To examine if, over a period of centuries, the Dutch medical establishment enjoyed a survival advantage over a population group with a comparable social background and level of education. Retrospective database research. We used documents which provided data on the births and deaths of 15,649 male and 659 female medical professionals and of 15,304 male clergy. We calculated the remaining life expectancy at the age of 25 of those generations born between the middle of the 16th century and the beginning of the 20th century. We applied event history analysis to estimate remaining life expectancy, dependently of survival at the age of 25. In doing this we applied Gompertz distribution and made a maximum likelihood estimation. From the middle of the 16th century onwards, the development of the life expectancy of medical professionals and clergy was comparable; it was characterised by a continuing increase in remaining life expectancy which was only interrupted in those generations who we...
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A negative educational gradient has been found for many causes of death. This association may be partly explained by confounding factors that affect both educational attainment and mortality. We correct the cause-specific educational... more
A negative educational gradient has been found for many causes of death. This association may be partly explained by confounding factors that affect both educational attainment and mortality. We correct the cause-specific educational gradient for observed individual background and unobserved family factors using an innovative method based on months lost due to a specific cause of death re-weighted by the probability of attaining a higher educational level. We use data on men with brothers from the Swedish Military Conscription Registry (1951-1983), linked to administrative registers. This dataset of some 700,000 men allows us to distinguish between five education levels and many causes of death. The empirical results reveal that raising the educational level from primary to tertiary would result in an additional 20 months of survival between ages 18 and 63. This improvement in mortality is mainly attributable to fewer deaths from external causes. The highly educated gain more than n...
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Research Interests: Demography and Population
ABSTRACT In hedendaagse discussies over immigratie wordt er meestal van uit-gegaan dat immigranten permanent in Nederland zullen blijven. Dat was immers ook grotendeels het geval voor de gastarbeiders uit de jaren zestig van de vorige... more
ABSTRACT In hedendaagse discussies over immigratie wordt er meestal van uit-gegaan dat immigranten permanent in Nederland zullen blijven. Dat was immers ook grotendeels het geval voor de gastarbeiders uit de jaren zestig van de vorige eeuw. De recent gearriveerde migranten zijn echter steeds minder geneigd om zich hier permanent te vestigen. Een groot deel van hen, meer dan 40%, verblijft maar kort in Nederland (Bijwaard 2005, 2010). Het is de vraag hoe deze ontwikkeling moet worden beoordeeld nu arbeidskrachten in de toekomst schaarser zul-len worden als gevolg van vergrijzing. Er zal vooral behoefte zijn aan kennismigratie, de arbeidsmigratie van hoogopgeleiden. Als deze migranten echter slechts voor korte tijd in ons land verblijven, zal hun (potentiële) bijdrage aan de Nederlandse economie beperkt blijven. Voor de bepaling van de economische bijdrage van migranten is het van groot belang om te weten welke migranten eerder vertrekken: de succesvolle migranten die een hoog inkomen genieten of de minder succesvolle, werkloze, migranten. In dit artikel zet ik op basis van recent onderzoek uiteen welke invloed arbeidsmarktsucces heeft op de verblijfsduur van de migranten. Er wordt daarbij onderscheid gemaakt naar geboorteland en andere achtergrondkenmerken van de migranten. Voor de in dit artikel vermelde onderzoeken is gebruikgemaakt van een uniek databestand dat, in samenwerking met het Centraal Bureau voor de Statistiek (CBS), is samengesteld op basis van administratieve gegevens. De informatie over migranten komt uit het Centraal Register Vreemdelingen (CRV) van de Immigratie-en Naturalisatiedienst (IND) en de Gemeentelijke Basisadministratie Persoonsgegevens (GBA) en betreft uitsluitend officiële, * Dr. Govert Bijwaard is onderzoeker bij het Nederlands Interdisciplinair Demografisch Instituut (NIDI). De auteur dankt het NORFACE research programme on Migration in Europe voor de financiële ondersteuning en is het CBS, in het bijzonder Ruben van Gaalen en Han Nicolaas, erkentelijk voor de hulp bij het verzamelen van de gegevens.
In this paper, we analyze the demographic factors that influence the migration dynamics of recent immigrants to The Netherlands. We show how we can allow for both permanent and temporary migrants. Results disclose differences among... more
In this paper, we analyze the demographic factors that influence the migration dynamics of recent immigrants to The Netherlands. We show how we can allow for both permanent and temporary migrants. Results disclose differences among migrants by migration motive and by country of origin and lend support to our analytical framework. Combining both models, for departure and returning to The
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Theory predicts that dismissing the 1 and 2 euro cent coins from the denominational range of the euro facilitates payment efficiency. To examine whether this theory holds true in practice, data were collected for the Netherlands before... more
Theory predicts that dismissing the 1 and 2 euro cent coins from the denominational range of the euro facilitates payment efficiency. To examine whether this theory holds true in practice, data were collected for the Netherlands before and after September 2004, which marks the day that retail stores were allowed to round all amounts at 5 euro cents. The data
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Research Interests: Intelligence and Health
We investigated the role that urbanization and plague may have played in changes in life expectancy amongst artists in the Low Countries who were born between 1450 and 1909. Artists can be considered to be representative of a middle-class... more
We investigated the role that urbanization and plague may have played in changes in life expectancy amongst artists in the Low Countries who were born between 1450 and 1909. Artists can be considered to be representative of a middle-class population living mostly in urban areas. The dataset was constructed using biographical information collected by the Rijksbureau voor Kunsthistorische Documentatie in The Hague, the Netherlands. As early as the beginning of the sixteenth century, life expectancy at age 20 amongst the artists had reached 40 years. After a substantial decline in the late sixteenth and the early seventeenth centuries, when plague hit the region, life expectancy at age 20 began to rise again, and this upward trend accelerated after 1850. The life expectancy of female artists commonly exceeded that of males, and sculptors had better survival prospects than painters. In comparison with elite groups in the Low Countries and elsewhere in Europe, life expectancy amongst the artists was rather high.
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Many studies show large differences in life expectancy across the range of education, intelligence, and socio-economic status. As educational attainment, intelligence, and socio-economic status are highly interrelated, appropriate methods... more
Many studies show large differences in life expectancy across the range of education, intelligence, and socio-economic status. As educational attainment, intelligence, and socio-economic status are highly interrelated, appropriate methods are required to disentangle their separate effects. The aim of this paper is to present a novel method to estimate gains in life expectancy specifically associated with increased education. Our analysis is based on a structural model in which education level, IQ at age 18 and mortality all depend on (latent) intelligence. The model allows for (selective) educational choices based on observed factors and on an unobserved factor capturing intelligence. Our estimates are based on information from health examinations of military conscripts born in 1944-1947 in The Netherlands and their vital status through age 66 (n = 39,798). Our empirical results show that men with higher education have lower mortality. Using structural models to account for educatio...
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Many migrants have non-labour motives to migrate and they differ substantially in their migration behaviour. Family migrants main migration motive is to join their future spouse. Thus, when their relation breaks down this influences their... more
Many migrants have non-labour motives to migrate and they differ substantially in their migration behaviour. Family migrants main migration motive is to join their future spouse. Thus, when their relation breaks down this influences their return decision. Using administrative panel data on the entire population of recent family immigrants to The Netherlands, we estimate the effect of a divorce on the hazard of leaving The Netherlands using the "timing-of-events" model. The model allows for correlated unobserved heterogeneity across the migration and the divorce processes. The family migrants are divided into three groups based on the Human Development Index (HDI) of their country of birth. We find that divorce has a large impact on the return of family migrants from less developed countries and less on the return of family migrants from developed countries. Young migrants with low income are influenced most by a divorce. We find some evidence of marriage for convenience fo...
Theory predicts that dismissing the 1 and 2 euro cent coins from the denominational range of the euro leads to more payment efficiency. To examine whether this theory holds true in practice, we collected data for the Netherlands before... more
Theory predicts that dismissing the 1 and 2 euro cent coins from the denominational range of the euro leads to more payment efficiency. To examine whether this theory holds true in practice, we collected data for the Netherlands before and after September 1 2004, which marks the day that retail stores were allowed to round all amounts at 5 euro cents. The data consist of wallet contents for three cross sections of individuals. We propose a multivariate Poisson- log Normal model to analyze these data. We find that rounding leads to less 1 and 2 cent coins in wallets, but that still other coins are over or underrepresented, thereby suggesting that the euro range does not yet lead to fully efficient payment behavior.
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Due to the shipping industry's international legal framework and the existence of loopholes in the system, an estimated 5-10 percent of substandard ships exist which are more likely to have incidents with high economic cost. This... more
Due to the shipping industry's international legal framework and the existence of loopholes in the system, an estimated 5-10 percent of substandard ships exist which are more likely to have incidents with high economic cost. This article uses ship life cycles to provide insight into the effectiveness of inspections on prolonging ship lives. We account for fluctuations in the relevant economic environment and the (possible time-varying) ship particulars. We use a unique dataset containing information on the timing of accidents, inspections, ship particular changes of more than fifty thousand ships over a 29 year time period (1978-2007). The results of our duration analysis reveal that the shipping industry is a relative safe industry but there is a possible over-inspection of vessels. It also reveals the need to improve transparency related to class withdrawals and changes of classification of the vessel. Another interesting finding is that for the majority of ship types an incre...
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In this paper we analyze the demographic factors that influence the migration dynamics of recent immigrants to The Netherlands. We show how we can allow for both permanent and temporary migrants. Based on data from Statistics Netherlands... more
In this paper we analyze the demographic factors that influence the migration dynamics of recent immigrants to The Netherlands. We show how we can allow for both permanent and temporary migrants. Based on data from Statistics Netherlands we analyze both the departure and the return from abroad for recent non-Dutch immigrants to The Netherlands. Results disclose differences among migrants by
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This paper analyzes empirically whether and if so to what extent later entrants in the European mobile telephony industry have a disadvantage vis-à-vis incumbents and early mover entrants. To analyze this question a dynamic model of... more
This paper analyzes empirically whether and if so to what extent later entrants in the European mobile telephony industry have a disadvantage vis-à-vis incumbents and early mover entrants. To analyze this question a dynamic model of market share development and a series of static models are considered. There is clear evidence of early mover advantage, mainly caused by the influence
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In survival analysis a large literature using frailty models, or models with unobserved heterogeneity, exist. In the growing literate on multiple spell multiple states duration models, or multistate models, modeling this issue is only at... more
In survival analysis a large literature using frailty models, or models with unobserved heterogeneity, exist. In the growing literate on multiple spell multiple states duration models, or multistate models, modeling this issue is only at its infant phase. Ignoring unobserved heteogeneity can, however, produce incorrect results. This paper presents how unobserved heterogeneity can be incorporated into multistate models, with an emphasis on semi-Markov multistate models with a mixed proportional hazard structure. First, the aspects of frailty modeling in univariate (proportional hazard, Cox) duration models are addressed and some important models with unobserved heterogeneity are discussed. Second, the domain is extended to modeling of parallel/clustered multivariate duration data with unobserved heterogeneity. The implications of choosing shared or correlated unobserved heterogeneity is highlighted. The relevant differences with recurrent events data is covered next. They include the...
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The emergence of a transitional labor market offers new opportunities to workers, but at the same time bears the risk of (new) inequalities. This paper deals with unequal chances on the transitional labor market in the Netherlands, in... more
The emergence of a transitional labor market offers new opportunities to workers, but at the same time bears the risk of (new) inequalities. This paper deals with unequal chances on the transitional labor market in the Netherlands, in particular for workers from the four largest immigrant groups: Turks, Moroccans, Surinamese and Antilleans. The data used are from the SPVA, the
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Nutritional conditions in early life may affect adult health, but prior studies of mortality have been limited to small samples. We evaluated the relationship between pre-/perinatal famine exposure during the Dutch Hunger Winter of... more
Nutritional conditions in early life may affect adult health, but prior studies of mortality have been limited to small samples. We evaluated the relationship between pre-/perinatal famine exposure during the Dutch Hunger Winter of 1944-1945 and mortality through age 63 years among 41,096 men born in 1944-1947 and examined at age 18 years for universal military service in the Netherlands. Of these men, 22,952 had been born around the time of the Dutch famine in 6 affected cities; the remainder served as unexposed controls. Cox proportional hazards models were used to estimate hazard ratios for death from cancer, heart disease, other natural causes, and external causes. After 1,853,023 person-years of follow-up, we recorded 1,938 deaths from cancer, 1,040 from heart disease, 1,418 from other natural causes, and 523 from external causes. We found no increase in mortality from cancer or cardiovascular disease after prenatal famine exposure. However, there were increases in mortality fr...