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Kosmos
Astronomia Astrofizyka
Inne

Kultura
Sztuka dawna i współczesna, muzea i kolekcje

Metoda
Metodologia nauk, Matematyka, Filozofia, Miary i wagi, Pomiary

Materia
Substancje, reakcje, energia
Fizyka, chemia i inżynieria materiałowa

Człowiek
Antropologia kulturowa Socjologia Psychologia Zdrowie i medycyna

Wizje
Przewidywania Kosmologia Religie Ideologia Polityka

Ziemia
Geologia, geofizyka, geochemia, środowisko przyrodnicze

Życie
Biologia, biologia molekularna i genetyka

Cyberprzestrzeń
Technologia cyberprzestrzeni, cyberkultura, media i komunikacja

Działalność
Wiadomości | Gospodarka, biznes, zarządzanie, ekonomia

Technologie
Budownictwo, energetyka, transport, wytwarzanie, technologie informacyjne

Demographic Research

  • OBJECTIVEThe paper explores the population effects of male preference stopping rules and of alternative combinations of fertility rates and male-biased birth sex ratios.METHODSThe ‘laboratory’ is a closed, stable population with five age groups and a dynamic process represented by a compact Leslie matrix. The new element is sex-selective abortion. We consider nine stopping rules, one with no male preference, two with male preference but no abortion, and six with male preference and the availability of abortion to achieve a desired number of male births. We calculate the probability distribution over the number of births and number of male births for each rule and work out the effects at the population level if the rule is adopted by all women bearing children. We then assess the impact of alternative combinations of fertility rates and male-biased sex ratios on the population.RESULTSIn the absence of sex-selective abortion, stopping rules generally have no effect on the male/female birth proportions in the population, although they can alter the fertility rate, age distribution, and rate of growth. When sex-selective abortion is introduced the effect on male/female proportions may be considerable, and other effects may also be quite different. The contribution of this paper is the quantification of effects that might have been predictable in general but which require model-based calculations to see how large they can be. As the paper shows, they can in fact be very large: a population in which sex-selective abortion is widely practised can look quite different from what it would otherwise be.

    http://www.demographic-research.org/volumes/vol31/25/#ref=rss 2014/10/02 - 10:40
  • BACKGROUNDRacial inequality in the U.S. is typically described in terms of stark categorical difference, as compared to the more gradational stratification based on skin color often said to prevail in parts of Latin America. However, nationally representative data with both types of measures have not been available to explicitly test this contrast.OBJECTIVEWe use novel, recently released data from the U.S. and 18 Latin American countries to describe household income inequality across the region by perceived skin color and racial self-identification, and examine which measure better captures racial disparities in each national context.RESULTSWe document color and racial hierarchies across the Americas, revealing some unexpected patterns. White advantage and indigenous disadvantage are fairly consistent features, whereas blacks at times have higher mean incomes than other racial populations. Income inequality can best be understood in some countries using racial categories alone, in others using skin color; in a few countries, including the U.S., a combination of skin color and self-identified race best explains income variation.CONCLUSIONSThese results complicate theoretical debates about U.S. racial exceptionalism and methodological debates about how best to measure race. Rather than supporting one measure over another, our cross-national analysis underscores race‟s multidimensionality. The variation in patterns of inequality also defies common comparisons between the U.S. on the one hand and a singular Latin America on the other.

    http://www.demographic-research.org/volumes/vol31/24/#ref=rss 2014/09/20 - 19:01
  • BACKGROUNDRelatively little research has been conducted on how economic recessions impact fertility intentions. In particular, uncertainty in reproductive intentions has not been examined in relation to economic shocks.OBJECTIVEThe purpose of this paper is to estimate the impact of individuals' perception of negative changes in both their own and their country's economic performance on reproductive intentions in Europe during the time of the 'Great Recession' (2006-2011). Crucially, we examine both intentions and stated certainty of meeting these intentions.METHODSUsing the 2011 Eurobarometer survey for 27 European countries, fertility intentions and reproductive uncertainty are regressed on individuals' perceptions of past trends in country's economic situation, household's financial situation, and personal job situation. Multilevel ordinal regressions models are run separately for people at parities zero and one as well as controlling for a set of socio-demographic variables.RESULTSA worsening in the households' financial situation, as perceived in the years of the economic crisis, does not affect people's fertility intentions but rather the certainty of meeting these intentions. This relationship holds true at the individual-level for childless people. The more negative the individual's assessment of the household's financial situation, the higher the reproductive uncertainty. While this works exclusively at the country-level for people at parity one, the higher the share of people‟s pessimism on households' financial situation in the country the more insecure individuals of such a country are about having additional children.CONCLUSIONSThe empirical evidence suggests that individuals' uncertainty about realising their fertility intentions has risen in Europe and is positively linked to people's perceived household financial difficulties. If European economies continue to fare poorly, fertility intentions could eventually start to decline in response to such difficulties.

    http://www.demographic-research.org/volumes/vol31/23/#ref=rss 2014/09/20 - 19:01
  • BACKGROUNDSurvival models accounting for unobserved heterogeneity (frailty models) play an important role in mortality research, yet there is no article that concisely summarizes useful relationships.OBJECTIVEWe present a list of important mathematical relationships that govern populations in which individuals differ from each other in unobserved ways. For some relationships we present proofs that, albeit formal, tend to be simple and intuitive.METHODSWe organize the article in a progression, starting with general relationships and then turning to models with stronger and stronger assumptions.RESULTSWe start with the general case, in which we do not assume any structure of the underlying baseline hazard, the frailty distribution, or their link to one another. Then we sequentially assume, first, a relative-risk model; second, a gamma distribution for frailty; and, finally, a Gompertz and Gompertz-Makeham specification for baseline mortality.COMMENTSThe article might serve as a handy overall reference to frailty models, especially for mortality research.

    http://www.demographic-research.org/volumes/vol31/22/#ref=rss 2014/09/20 - 19:01
  • BACKGROUNDThe majority of crime is committed by young men, and young men comprise the majority of the military-base population. The confluence of these two empirical regularities invites a scientific look at the contribution of a military base to criminal activity in ist geographic periphery.OBJECTIVEWe estimate the impact on criminal activity of the massive base realignments and closures that occurred in Germany for the period 2003-2007. In particular, we examine breaking and entering, automobile-related crime, violent crime, and drug-related crime.METHODSWe use a fixed-effect model to account for time-invariant unobservables in a panel of 298 military bases. We also take advantage of geographic information system software to mitigate issues arising from the spatial nature of the dataset.RESULTSThe estimates indicate that the base realignments and closures did not have a significant impact on criminal activity surrounding the base. Traditional correlates of crime remain statistically significant in our specifications.CONCLUSIONSAlthough crime is largely committed by young men, we find that the closure of military bases, which are staffed primarily by young men, does not have an impact on criminal activity. For matters of regional policy, we find that arguments pertaining to criminal activity generated by military bases are not supported by the data.COMMENTSEconomic well-being, as measured by real GNP and relative disposable income, is negatively associated with crime. Higher unemployment has a positive association. Regions with higher share of foreigners also have higher crime levels.

    http://www.demographic-research.org/volumes/vol31/21/#ref=rss 2014/09/20 - 19:01
  • BACKGROUNDRacial and ethnic diversity continues to grow in communities across the United States, raising questions about the extent to which different ethnic groups will become residentially integrated.OBJECTIVEWhile a number of studies have examined the residential patterns of pan-ethnic groups, our goal is to examine the segregation of several Asian and Hispanic ethnic groups - Cubans, Dominicans, Mexicans, Puerto Ricans, Salvadorans, Asian Indians, Chinese, Filipinos, Japanese, Koreans, and Vietnamese. We gauge the segregation of each group from several alternative reference groups using two measures over the 1980 to 2010 period.RESULTSWe find that the dissimilarity of Hispanics and Asians from other groups generally held steady or declined, though, because most Hispanic and Asian groups are growing, interaction with Whites also often declined. Our analyses also indicate that pan-ethnic segregation indexes do not always capture the experience of specific groups. Among Hispanics, Mexicans are typically less residentially segregated (as measured using the dissimilarity index) from Whites, Blacks, Asians, and other Hispanics than are other Hispanic-origin groups. Among Asian ethnic groups, Japanese and Filipinos tend to have lower levels of dissimilarity from Whites, Blacks, and Hispanics than other Asian groups. Examining different dimensions of segregation also indicates that dissimilarity scores alone often do not capture to what extent various ethnic groups are actually sharing neighborhoods with each other. Finally, color lines vary across groups in some important ways, even as the dominant trend has been toward reduced racial and ethnic residential segregation over time.CONCLUSIONSThe overarching trend is that ethnic groups are becoming more residentially integrated, suggestive of assimilation, though there is significant variation across ethnic groups.

    http://www.demographic-research.org/volumes/vol31/20/#ref=rss 2014/09/03 - 19:07
  • BACKGROUNDThe gamma-Gompertz model is a fixed frailty model in which baseline mortality increases exponentially with age, frailty has a proportional effect on mortality, and frailty at birth follows a gamma distribution. Mortality selects against the more frail, so the marginal mortality rate decelerates, eventually reaching an asymptote. The gamma-Gompertz is one of a wider class of frailty models, characterized by the choice of baseline mortality, effects of frailty, distributions of frailty, and assumptions about the dynamics of frailty.OBJECTIVETo develop a matrix model to compute all the statistical properties of longevity from the gamma-Gompertz and related models.METHODSI use the vec-permutation matrix formulation to develop a model in which individuals are jointly classified by age and frailty. The matrix is used to project the age and frailty dynamics of a cohort and the fundamental matrix is used to obtain the statistics of longevity.RESULTSThe model permits calculation of the mean, variance, coefficient of variation, skewness and all moments of longevity, the marginal mortality and survivorship functions, the dynamics of the frailty distribution, and other quantities. The matrix formulation extends naturally to other frailty models. I apply the analysis to the gamma-Gompertz model (for humans and laboratory animals), the gamma-Makeham model, and the gamma-Siler model, and to a hypothetical dynamic frailty model characterized by diffusion of frailty with reflecting boundaries. The matrix model permits partitioning the variance in longevity into components due to heterogeneity and to individual stochasticity. In several published human data sets, heterogeneity accounts for less than 10% of the variance in longevity. In laboratory populations of five invertebrate animal species, heterogeneity accounts for 46% to 83% of the total variance in longevity.

    http://www.demographic-research.org/volumes/vol31/19/#ref=rss 2014/09/03 - 19:07
  • BACKGROUNDMost research on women’s labor force return after childbirth concentrates on industrialized countries in the West; the link between economic swings and mothers’ work-return behavior is rarely addressed. This study closes these gaps by focusing on South Korea, a developed society in East Asia that has in recent decades witnessed increases in female labor force participation and dramatic economic ups and downs. This is the first relevant study on South Korea.OBJECTIVEThis study examines how women’s labor force return after childbirth (with and without career interruption) and their career prospects upon work return varied before, during, and after the Asian financial crisis in South Korea.METHODSLogistic and hazard regression models were applied to the Korea Labor and Income Panel Study (KLIPS waves 1-10).RESULTSThe study reveals an increase in women’s immediate work return after childbirth without career interruption since the 1980s. The Asian financial crisis boosted this immediate return pattern. The implementation of job-protected maternity leave further contributed to this pattern. Women who underwent career interruption at first birth were also more likely to re-enter the labor market during and after the crisis than before. Downward occupational moves were especially common during the period of financial crisis.CONCLUSIONSThe results suggest that the Asian financial crisis triggered a noticeable change in women’s post-birth work-return behavior. The economic volatility pushed mothers to hold onto their role in the labor force more strongly than before.

    http://www.demographic-research.org/volumes/vol31/18/#ref=rss 2014/08/30 - 19:37
  • BACKGROUNDRapid population aging and increasing racial/ethnic and immigrant/native diversity make a broad documentation of U.S. health patterns during both mid- and late life particularly important.OBJECTIVEWe aim to better understand age- and gender-specific racial/ethnic and nativity differences in physical functioning and disability among adults aged 50 and above.METHODSWe aggregate 14 years of data from the National Health Interview Survey and calculate age- and gender-specific proportions of physical functioning and two types of disability for each population subgroup.RESULTSMiddle-aged foreign-born individuals in nearly every subgroup exhibit lower proportions of functional limitations and disability than U.S.-born whites. This pattern of immigrant advantage is generally reversed in later life. Moreover, most U.S.-born minority groups have significantly higher levels of functional limitations and disability than U.S.-born whites in both mid- and late life.CONCLUSIONSHigher levels of functional limitations and disability among U.S.-born minority groups and immigrant populations in older adulthood pose serious challenges for health providers and policymakers in a rapidly diversifying and aging population.

    http://www.demographic-research.org/volumes/vol31/17/#ref=rss 2014/08/26 - 16:30
  • BACKGROUNDIn longitudinal research the loss of sample members between waves is a possible source of bias. It is therefore crucial to analyse attrition.OBJECTIVEThis paper analyses attrition in a longitudinal study on family and fertility, by distinguishing between attrition due to non-contact and attrition due to non-cooperation.METHODSBased on the first two waves of the Austrian Generations and Gender Survey, the two components of attrition are studied separately by using bivariate as well as multivariate methods. Moreover, overall dropout – the combination of both components – is analysed. Apart from various socio-economic characteristics and data collection information, the study focuses on fertility-relevant variables such as fecundity, fertility intentions, sexual orientation, and traditional attitudes.RESULTSFecundity, fertility intentions, and homosexual relationships are associated with higher attrition due to non-cooperation in bivariate analyses, but have no explanatory power in the multivariate model. Pregnancy and traditional attitudes towards marriage are associated with significantly lower attrition due to non-cooperation in the multivariate context. Overall dropout is significantly lower only among persons with traditional attitudes towards marriage, although small in size and statistical significance. Moreover, various individual and regional characteristics are significantly associated with dropout, with differences between attrition due to non-contact and attrition due to non-cooperation.CONCLUSIONSDetailed insights into attrition are not only important when using longitudinal data and interpreting results, but also for the design of future data collections. The Austrian GGS panel has a relatively low dropout (22%) and is affected by a small bias towards familyoriented persons as well as less-educated respondents and persons with migration backgrounds, but the data can be used without concern about selectivity.

    http://www.demographic-research.org/volumes/vol31/16/#ref=rss 2014/08/22 - 10:51
  • BACKGROUNDDuring recent decades women have made considerable advances in education and the labor market, even in fast-track professions such as law, medicine, and academia. While women have entered high-status professions, the career paths of some jobs have changed little and are still inflexible, which implies that professional gains may be offset by familial losses.OBJECTIVEWe investigate continued childbearing, focusing on the relationship between occupation and second and third births, among highly educated men and women in three high-status professions.METHODSWe analyze the determinants of having a second or a third birth using longitudinal data from population registers in Sweden, 1991-2009. We use descriptive statistics and logistic models.RESULTSNet of demographic and socioeconomic controls, medical doctors are more likely to continue childbearing than lawyers and academics, irrespective of parity and gender. The patterns that emerge are independent of income. Public sector work is conducive to continued childbearing, especially for women.CONCLUSIONSAlthough there are more opportunities to combine career and family in Sweden than in many other countries, this does not hold equally for all. The results indicate that working conditions and career structures contribute to making it easier for some groups than others to combine a professional career and children. Patterns that emerge reflect that women and men are not equally sensitive to career structures that imply a tradeoff between career and children at an early stage of the career. This puts policies promoting work and family for all into perspective.

    http://www.demographic-research.org/volumes/vol31/15/#ref=rss 2014/08/08 - 16:31
  • BACKGROUNDThe growing interest in pathways, the increased availability of life-history data, innovations in statistical and demographic techniques, and advances in software technology have stimulated the development of software packages for multistate modeling of life histories.OBJECTIVEIn the paper we list and briefly discuss several software packages for multistate analysis of life-history data. The packages cover the estimation of multistate models (transition rates and transition probabilities), multistate life tables, multistate population projections, and microsimulation.METHODSBrief description of software packages in a historical and comparative perspective.RESULTSDuring the past 10 years the advances in multistate modeling software have been impressive. New computational tools accompany the development of new methods in statistics and demography. The statistical theory of counting processes is the preferred method for the estimation of multistate models and R is the preferred programming platform.CONCLUSIONSInnovations in method, data, and computer technology have removed the traditional barriers to multistate modeling of life histories and the computation of informative lifecourse indicators. The challenge ahead of us is to model and predict individual life histories.

    http://www.demographic-research.org/volumes/vol31/14/#ref=rss 2014/08/08 - 16:31
  • BACKGROUNDIn Spain, foreign-born women are disproportionately employed in housework or care work, and quantitative research has shown that female migrants are disadvantaged relative to male migrants in the occupational status of their first job in Spain. However, the process that created this female penalty has not yet been explored.OBJECTIVEIn this paper, we focus on female occupational mobility at migration and during settlement in Spain. First, we compare female and male labour mobility at migration. Second, we identify the main socio-demographic factors which increase the likelihood that the first job a foreign-born woman holds in Spain will be as a cleaner or a domestic worker. Third, we investigate female labour mobility from the time of migration, particularly trajectories that lead away from the cleaning and domestic occupations, and consider the importance of the assimilation process in occupational mobility.METHODSWe apply quantitative methods to Spain’s 2007 National Immigrant Survey (Encuesta Nacional de Inmigrantes), using descriptive (mobility matrixes) and simple and multinomial logistic regression analyses. We include the main socio-demographic, family, and migratory characteristics of immigrants in the explanatory models.RESULTSThe results of our analysis revealed that female migrants to Spain are more likely than their male counterparts to experience occupational downgrading at the time of migration, and that 41.6% of women work in domestic services in their first job in Spain. Finally, our results have demonstrated that, although occupational immobility is common among female migrants in Spain, movement out of domestic services is possible, especially for the most assimilated immigrant women.CONCLUSIONSThis paper contextualises female immigration in Spain, attributing the labour market choices made by female migrants to the externalisation of domestic and cleaning occupations in private households, and to the gender segmentation of the labour market.

    http://www.demographic-research.org/volumes/vol31/13/#ref=rss 2014/08/01 - 05:03
  • BACKGROUNDStudies on fertility in Poland focus on the turbulent transition period and its consequences. However, during state socialism significant societal and demographic changes took place.OBJECTIVEThis article studies the macro-level relationship between education and completed fertility of Polish women born between 1930 and 1959, and tries to assess how changes in women’s educational structure affected fertility.METHODSUsing data from the large-scale Fertility Survey 2002 that accompanied the Polish population census, I first look into fertility trends by education and five-year cohorts. Then, by applying Cho’s and Retherford’s decomposition analysis and direct standardisation, I assess the role of women’s educational expansion in fertility changes.RESULTSDespite profound structural changes and the ruling egalitarian ideology, the educational gradient in completed fertility remained strongly negative in all analysed cohorts. The observed decline in completed fertility from 2.51 in the 1930-34 cohort to 2.22 in the 1955-59 cohort can be explained by the expansion of female education. Had the educational structure not changed, the completed fertility of the youngest cohort would have been slightly higher than that of the oldest cohort.CONCLUSIONSUnder state socialism in Poland, better-educated women had on average fewer children than the less educated. The expansion of female education played an important role in fertility decline.

    http://www.demographic-research.org/volumes/vol31/12/#ref=rss 2014/08/01 - 05:03
  • BACKGROUNDThe paper is motivated by the need for improved social evaluation of prospective demographic change in order to better inform policies that are designed to reduce the very long-run costs of population ageing and to achieve sustainable economic development.OBJECTIVEWhat is the very long-run social value of a given demographic path? What is the value of changes in mortality, immigration, fertility, and labour force participation? How important are shorter-term demographic changes relative to very long-term effects in determining the social value of the demographic path?METHODSA new simulation method is applied for socially evaluating demographic paths, by separating a demographic path into a stable population component and a transition path component. Sensitivity analyses are conducted with respect to demographic assumptions, labour force participation assumptions, and consumption needs by age, returns to scale, and intergenerational value judgements.RESULTSThe application to Australia shows the considerable social cost, in terms of the loss of discounted consumption per capita, of improvements in mortality and gains from higher immigration and increased participation. The effect of fertility, however, is very sensitive to assumptions about the age-specific consumption needs of the population and social value judgements about intergenerational equity.CONCLUSIONSOur method socially evaluates the very long-run implications of specified constant fertility, mortality, and migration, giving consideration to both the transition path and the ultimate stable state. Mortality improvement is costly and higher immigration is beneficial. The impact of higher fertility is sensitive to assumptions about consumption needs and intergenerational equity.

    http://www.demographic-research.org/volumes/vol31/11/#ref=rss 2014/08/01 - 05:03
  • BACKGROUNDCross-national research suggests that married people have higher levels of well-being than cohabiting people. However, relationship quality has both positive and negative dimensions. Researchers have paid little attention to disagreements within cohabiting and married couples.OBJECTIVEThis study aims to improve our understanding of the meaning of cohabitation by examining disagreements within marital and cohabiting relationships. We examine variations in couples’ disagreements about housework, paid work and money by country and gender.METHODSThe data come from the 2004 European Social Survey. We selected respondents living in a heterosexual couple relationship and aged between 18 and 45. In total, the study makes use of data from 22 European countries and 9,657 people. Given that our dependent variable was dichotomous, we estimated multilevel logit models, with (1) disagree and (0) never disagree.RESULTSWe find that cohabitors had more disagreements about housework, the same disagreements about money, but fewer disagreements about paid work than did married people. These findings could not be explained by socio-economic or demographic measures, nor did we find gender or cross-country differences in the association between union status and conflict.CONCLUSIONSCohabiting couples have more disagreements about housework but fewer disagreements about paid work than married people. There are no gender or cross-country differences in these associations. The results provide further evidence that the meaning of cohabitation differs from that of marriage, and that this difference remains consistent across nations.

    http://www.demographic-research.org/volumes/vol31/10/#ref=rss 2014/07/23 - 11:16
  • BACKGROUNDFor the most part, demographers have relied on the ever-growing body of sample surveys collecting full birth history to derive total fertility estimates in less statistically developed countries. Yet alternative methods of fertility estimation can return very consistent total fertility estimates by using only basic demographic information.OBJECTIVEThis paper evaluates the consistency and sensitivity of the reverse survival method -- a fertility estimation method based on population data by age and sex collected in one census or a single-round survey.METHODSA simulated population was first projected over 15 years using a set of fertility and mortality age and sex patterns. The projected population was then reverse survived using the Excel template FE_reverse_4.xlsx, provided with Timæus and Moultrie (2012). Reverse survival fertility estimates were then compared for consistency to the total fertility rates used to project the population. The sensitivity was assessed by introducing a series of distortions in the projection of the population and comparing the difference implied in the resulting fertility estimates.RESULTSThe reverse survival method produces total fertility estimates that are very consistent and hardly affected by erroneous assumptions on the age distribution of fertility or by the use of incorrect mortality levels, trends, and age patterns. The quality of the age and sex population data that is ‘reverse survived’ determines the consistency of the estimates. The contribution of the method for the estimation of past and present trends in total fertility is illustrated through its application to the population data of five countries characterized by distinct fertility levels and data quality issues.CONCLUSIONSNotwithstanding its simplicity, the reverse survival method of fertility estimation has seldom been applied. The method can be applied to a large body of existing and easily available population data -- both contemporary and historical -- that so far has remained largely under-exploited, and contribute to the study of fertility levels and trends.

    http://www.demographic-research.org/volumes/vol31/9/#ref=rss 2014/07/16 - 10:58
  • BACKGROUNDWomen, who generally do more unpaid and less paid work than men, have greater incentives to stay in marriages than cohabiting unions, which generally carry fewer legal protections for individuals that wish to dissolve their relationship. The extent to which cohabitation is institutionalized, however, is a matter of policy and varies substantially by country. The gender gap in paid and unpaid work between married and cohabiting individuals should be larger in countries where cohabitation is less institutionalized and where those in cohabiting relationships have relatively fewer legal protections should the relationship dissolve, yet few studies have explored this variation.OBJECTIVEUsing time diary data from France, Italy, and the United States, we assess the time men and women devote to paid and unpaid work in cohabiting and married couples. These three countries provide a useful diversity in marital regimes for examining these expectations: France, where cohabitation is most “marriage like” and where partnerships can be registered and carry legal rights; the United States, where cohabitation is common but is short-lived and unstable and where legal protections vary across states; and Italy, where cohabitation is not common and where such unions are not legally acknowledged and less socially approved than in either France or the United States.RESULTSCohabitating men’s and women’s time allocated to market and nonmarket work is generally more similar than married men and women. Our expectations about country differences are only partially borne out by the findings. Greater gender differences in the time allocated to market and nonmarket work are found in Italy relative to either France or the U.S.

    http://www.demographic-research.org/volumes/vol31/8/#ref=rss 2014/07/11 - 17:39
  • BACKGROUNDDespite a long interest in the historical fertility transition, there is still a lack of knowledge about disaggregated patterns that could help us understand the mechanisms behind the transition. In previous research the widely held view is that there was a change in the association between social status and fertility in conjunction with the fertility transition, implying that fertility went from being positively connected to social status (higher status was connected with higher fertility) to being negatively associated with fertility.OBJECTIVEThe aim of this collection is to study socioeconomic patterns in the fertility transition in a variety of contexts using similar approaches and measures of socioeconomic status.METHODSAll contributions use different kinds of micro-level socioeconomic and demographic data and statistical models in the analysis. Data either come from census-like records or population registers.CONCLUSIONSThere is no consistent evidence for the hypothesis that socioeconomic status was positively related to fertility before the demographic transition. While such a correlation was clearly present in some contexts it was clearly not in other contexts. There is more unanimous support for the idea that the upper-and middle classes acted as forerunners in the transition, while especially farmers were late to change their fertility behavior. It is also evident that both parity-specific stopping and prolonged birth intervals (spacing) were important in the fertility transition.

    http://www.demographic-research.org/volumes/vol31/7/#ref=rss 2014/07/11 - 17:39
  • BACKGROUNDMore than downplayed, the role of men in the demographic analysis of reproduction has been entirely neglected. However, male fertility can be an important issue for exploring how economic and employment uncertainties relate to fertility and family dynamics.OBJECTIVEThis paper intends to study fertility variations over time, relying solely on data referring to father’s socio-demographic characteristics; in particular, their age, education level, and employment status.METHODSWe use a combination of Labor Force Survey and Demographic Statistics data on population and Vital Statistics on births to estimate male fertility indicators and fertility differentials by education level and employment status, for the period 1992-2011 in Greece. In addition, over-time developments in male TFR are separated into structural (education-specific and employment-specific distributions) and behavioral (fertility, per se) changes.RESULTSWe find that the male fertility level is declining, the fertility pattern is moving into higher ages, and the reproduction period for men is getting shorter. From 1992 up to 2008, changes in male fertility were mostly driven by behavioral rather than compositional factors. However, the decline of male fertility over the period of economic recession (2008-2011) is largely attributed to the continuous decrease in the proportions of employed men.CONCLUSIONSThe study suggests that male fertility merits further exploration. In particular, years of economic downturn and countries where household living standards are mostly associated with male employment, a father’s employability is likely to emerge as an increasingly important factor of fertility outcomes.

    http://www.demographic-research.org/volumes/vol31/6/#ref=rss 2014/07/09 - 20:19
  • BACKGROUNDEducation is positively associated with completed fertility rate (CFR) among men in Nordic countries, but the age patterns of fertility by educational level are poorly documented. Moreover, it is not known what parities contribute to the higher CFR among more highly educated men.OBJECTIVETo describe men’s fertility by age, parity, and education in Finland.METHODSThe study is based on register data covering the male cohort born in 1940‒1950 (N=38,838). Education was measured at ages 30‒34 and classified as basic, lower secondary, upper secondary, and tertiary. Fertility was measured until ages 59‒69. We calculated completed and age-specific fertility rates, and decomposed the educational gradient in CFR into parity-specific contributions.RESULTSThe more highly educated men had more children (CFR: basic 1.71 and tertiary 2.06), had them later (mean age at having the first child: basic 26.1 and tertiary 28.1), and had them within a shorter interval (interquartile range of age at having the first child: basic 5.8 and tertiary 5.2). The educational gradient in the cumulative fertility rate was negative at young ages but turned positive by the early thirties. High levels of childlessness among those with a basic education explained three-quarters of the CFR difference between the lowest and highest educational groups. Fertility at ages above 45 was low and did not widen the educational gradient in CFR.CONCLUSIONSThe fact that highly educated men have more children than their counterparts with less education is largely attributable to higher fertility levels at older ages and the lower probability of remaining childless. Variation in fertility timing and quantity is wider among men with a low level of education.

    http://www.demographic-research.org/volumes/vol31/5/#ref=rss 2014/07/09 - 20:19
  • BACKGROUNDMaintaining cognitive functioning through mid- to late-life is relevant for the individual and societal aim of active ageing. Evidence shows considerable stability in individual-level rank-ordering of cognitive functioning, but little attention has been given to cohort performance over the life cycle and macro-level factors that could affect it.OBJECTIVEThe main goal of this paper is to address cross-national variation in mental performance from younger to older ages.METHODSUsing a quasi-longitudinal approach, we compare the relative country ranking in standardised mathematical test scores at teen age in 1964 from the First International Mathematics Study (FIMS) and cognitive test performance at mid-life in 2004, based on the Survey of Health, Ageing and Retirement in Europe (SHARE) for the cohort born between 1949 and 1952.RESULTSOur results show that those countries which had the highest scores in math tests taken by 13 years old grade level students are not the same countries that, 40 years later, have the top performing scores in cognitive tests among mid-age adults.CONCLUSIONSThis article highlights the importance of considering country-level influences on cognitive change over the life cycle, in addition to individual characteristics, and provides some descriptive findings that could be incorporated with further research on the link between specific contextual factors and cognitive functioning.

    http://www.demographic-research.org/volumes/vol31/4/#ref=rss 2014/07/06 - 13:43
  • BACKGROUNDA large body of research has compared relationship satisfaction and quality in cohabiting versus married relationships. Despite increased recognition of couples in living apart together (LAT) relationships, very little research has examined the experiences of couples in LAT relationships compared to co-residential unions.OBJECTIVEOur aim is to develop knowledge about the experiences of different union types by investigating relationship satisfaction of people in LAT, cohabiting, and marital relationships. We differentiate those with intentions to marry for cohabiters, and those with intentions to marry or live together in LAT relationships. We also examine differences by gender and country.METHODSUsing data from Wave 1 of the Generations and Gender Survey in France, Germany, Australia, and Russia (n = 9,604), OLS regressions are estimated to investigate a) differences in relationship satisfaction across relationship types, and b) across countries.RESULTSMarried people have the highest levels of relationship satisfaction. People in non-marital unions with intentions to marry or live together are significantly more satisfied than those without marriage or cohabitation intentions. Those in LAT relationships with no intentions to live together have the lowest levels of relationship satisfaction. There is evidence of cross-national variation with differences in relationship satisfaction by union type most pronounced in Australia and Russia. Gender differences are found with women reporting lower levels of relationship satisfaction than men.CONCLUSIONSLAT relationships are qualitatively different to co-residential unions. It is important to further develop our understanding of the experiences of couples in these relationships.

    http://www.demographic-research.org/volumes/vol31/3/#ref=rss 2014/07/03 - 22:41
  • BACKGROUNDFactors including smoking, drinking, substance abuse, obesity, and health care have all been shown to affect health and longevity. The relative importance of each of these factors is disputed in the literature, and has been assessed through a number of methods.OBJECTIVEThis paper uses a novel approach to identify factors responsible for interstate mortality variation. It identifies factors through their imprint on mortality patterns and can therefore identify factors that are difficult or impossible to measure directly, such as sensitive health behaviors.METHODSThe analysis calculates age-standardized death rates by cause of death from 2000-2009 for white men and women separately. Only premature deaths between ages 20-64 are included. Latent variables responsible for mortality variation are then identified through a factor analysis conducted on a death-rate-by-state matrix. These unobserved latent variables are inferred from observed mortality data and interpreted based on their correlations with individual causes of death.RESULTSSmoking and obesity, substance abuse, and rural/urban residence are the three factors that make the largest contributions to state-level mortality variation among males. The same factors are at work for women but are less vividly revealed. The identification of factors is supported by a review of epidemiologic studies and strengthened by correlations with observable behavioral variables. Results are not sensitive to the choice of factor-analytic method used.CONCLUSIONSThe majority of interstate variation in mortality among white working-age adults in the United States is associated with a combination of smoking and obesity, substance abuse and rural/urban residence.

    http://www.demographic-research.org/volumes/vol31/2/#ref=rss 2014/07/02 - 05:29
  • BACKGROUNDEvolutionary theory predicts that grandparental investment should support the childbearing of adult children, but evidence from contemporary developed countries is mixed or relatively weak. One possible reason for this lack of clarity is that grandparental support for fertility may vary by country, the economic situation of the adult child’s household, and the lineage and the sex of the grandparent.OBJECTIVEWe investigate the associations between grandparental investments and the intentions of mothers to have a second or third child in four European countries - Bulgaria, France, Lithuania, and Norway - while paying special attention to effect of the country, the financial security of the household, and the different grandparent types.METHODSUsing the first wave data (2004-08) of the Generations and Gender Surveys, we measured grandparental investment by the amount of child care help and emotional support mothers reported receiving from their parents. We studied these factors with binary logistic regression analysis.RESULTSBoth emotional support and child care help from grandparents were associated with increased fertility intentions in France and Norway. Emotional support was also associated with increased fertility intentions in Bulgaria, while grandparental child care help was associated with decreased intentions in Lithuania. Emotional support was more strongly associated with fertility intentions in financially secure households. Emotional support received from a maternal grandmother, a maternal grandfather, and a paternal grandmother; and child care help received from a maternal grandfather; were associated with an increased probability that a mother would report the intention to have another child.CONCLUSIONSGrandparental investment, especially emotional support, appears to be most influential in wealthier European countries and among more financially secure families. When a family’s socioeconomic situation and the broader environment are generally favourable for having several children, grandparents may provide the "extra push" that supports the intention to have another child.

    http://www.demographic-research.org/volumes/vol31/1/#ref=rss 2014/07/02 - 05:29
  • BACKGROUNDWith increasing levels of student loan debt, the path to economic stability may be less smooth than it was for earlier generations of college graduates. This paper explores this emerging trend by assessing whether or not student loan debt influences family formation.OBJECTIVEThe objective of this study is to examine whether student loan debt delays marriage in young adulthood, whether or not the relationship between student loan debt and marriage differs for women and for men, and if this relationship attenuates during the years immediately after college graduation.METHODSWe estimate a series of discrete-time hazard regression models predicting the odds of first marriage as a function of time-varying student loan debt balance, using a nationally representative sample of bachelor’s degree recipients from the 1993 Baccalaureate and Beyond Longitudinal Study (N = 9,410).RESULTSWe find that the dynamics of loan repayment are related to marriage timing for women, but not for men. Specifically, an increase of $1,000 in student loan debt is associated with a reduction in the odds of first marriage by two percent a month among female bachelor degree recipients during the first four years after college graduation. This relationship attenuates over time.CONCLUSIONSOur study lends support to the proposition that the financial weight of monthly loan repayments impedes family formation in the years immediately following college graduation -- however, only for women. This finding questions traditional models of gender specialization in family formation that emphasize the economic resources of men.

    http://www.demographic-research.org/volumes/vol30/69/#ref=rss 2014/06/14 - 13:56
  • BACKGROUNDSpatial inequalities in human development are of great concern to international organisations and national governments. Demographic indicators like the infant mortality rate are important measures for determining these inequalities. Using demographic indicators over long time periods at relatively high levels of geographical detail, we can examine the long-term continuities and changes in spatial inequalities.OBJECTIVEThis paper presents the initial outcomes of a larger project that aims to analyse spatial variation in infant survival across Europe over the last 100 years. In this paper, we focus on spatial disparities in infant survival in 1910. At that time, the longevity revolution was still at an early stage. We look at general spatial variation patterns within and across countries, and discuss some of the challenges related to the comparativeness of the data.METHODSWe link official infant mortality data from more than 5,000 European regions and localities for the period around 1910 to a European historical GIS of administrative boundaries. The data are analysed using descriptive spatial analysis techniques.RESULTSIn 1910, a number of countries in northern and western Europe led the longevity revolution in Europe, with the area of low infant mortality also extending into the northwestern parts of the German Empire. Other areas with low infant mortality levels included the Belgian region of Wallonia, most parts of Switzerland, as well as central and south-western France. In eastern and southern Europe, we find significant variation within and across countries, which might stem in part from data quality problems.

    http://www.demographic-research.org/volumes/vol30/68/#ref=rss 2014/06/12 - 14:23
  • BACKGROUNDMeasles is a highly contagious but vaccine-preventable disease. Gender differences in measles vaccination outcomes have been widely reported in India.OBJECTIVEAn overlooked factor is whether female children are less likely to be vaccinated age-appropriately.METHODSIn this paper we use data from the nationally representative 2008 District Level Household Survey (DLHS) to analyse if there are any gender differences in the propensity to vaccinate a child for measles, and, among the vaccinated sample, whether there are any gender differences in the probability of age-appropriate measles vaccination.RESULTSOur analysis confirms that girls have both a significantly lower probability of being vaccinated and of being vaccinated age-appropriately.

    http://www.demographic-research.org/volumes/vol30/67/#ref=rss 2014/06/12 - 14:23
  • BACKGROUNDThe paper describes the origins of the Value of Children (VOC) approach to the cross-cultural research on fertility behavior around the Pacific Rim, and critically discusses its shortcomings at this stage.OBJECTIVEThe paper then demonstrates how the approach derives its theoretical coherence from the theory of social production functions, making reference to empirical evidence.RESULTSThe VOC approach combines a multi-level and action-oriented theoretical model of generative behavior based on the principles of methodological individualism with the welfare maximizing assumptions derived from social production function theory, to create a comprehensive explanatory program.CONCLUSIONSThe VOC approach extends economic theories of fertility:Whereas traditional economic theories emphasize the costs of children, the VOC approach also encompasses the supply side of children, i.e., the benefits children bring to their (potential) parents under variable social and economic conditions.COMMENTSThe paper outlines future extensions of the VOC approach. The question here is if and to what extent the production of social welfare through parenthood is substitutable by other production modes, and whether children as intermediate goods compete or are complemented by welfare production in other life domains.

    http://www.demographic-research.org/volumes/vol30/66/#ref=rss 2014/06/06 - 15:42
  • BACKGROUNDDespite the increasing prevalence of cohabitation, knowledge of how socio-economic homogamy affects the stability of cohabiting unions is scant. Few studies have compared the effects of homogamy in both ascribed and achieved socio-economic status on union dissolution.OBJECTIVEOur aim is to determine how homogamy and heterogamy in educational level and parental social class affect the risk of cohabitation dissolution in Finland.METHODSWe use unique Finnish register data that includes information on non-marital cohabitation. Cox regression is used to analyse the risk of dissolution in 20,452 cohabitations. We examine the dissolution rates in all possible combinations of partner status, and analyse how these estimates deviate from the main effects of each partner’s status.RESULTSAccording to the findings, homogamy in parental social class is of little consequence in cohabitation dissolution, although cohabitations between people from upper-white-collar and farmer families are disproportionately likely to dissolve. Educational differences between partners are more significant determinants of cohabitation stability: extreme heterogamy is associated with an increased separation risk, and homogamy decreases the separation risk among cohabitors with a higher university degree.CONCLUSIONSIn line with the perception that personal achievement is more significant than social origins in contemporary union dynamics, similarity in educational level increases cohabitation stability more than similarity in socio-economic origin. Although previous Nordic studies report little or no association between educational homogamy or heterogamy and marriage dissolution, our study shows that educational differences do matter in cohabiting unions.

    http://www.demographic-research.org/volumes/vol30/65/#ref=rss 2014/06/06 - 15:42
  • BACKGROUNDEntering employment and achieving a stable position in the labour market are considered important preconditions for childbearing. Existing studies addressing the relationship between work experience and the timing of parenthood focus exclusively on Western Europe and North America. By adding an Eastern European context before and after societal transformation, this study contributes to a more comprehensive account of the role of work experience in first-birth timing in Europe.OBJECTIVEWe investigate how work experience and career development are related to the timing of parenthood in two diverse contexts in Estonia, state socialism and the market economy, and how it varies by gender and nativity.METHODSThe data used come from the Estonian Health Interview Survey 2006-2007. We estimate piecewise constant event history models to analyse the transition to first birth.RESULTSOur results suggest that in the market economy work experience became more important in the decision to enter parenthood. In the market economy the importance of work experience to entering parenthood became more similar for women and men. Non-native-origin men and women’s timing of parenthood appears to have become detached from their career developments. The article discusses mechanisms that may underlie the observed patterns.CONCLUSIONSOur study shows how work experience gained importance as a precondition for parenthood in the transition to a market economy. This lends support to the view that the increasing importance of work experience is among plausible drivers of the postponement transition that extended to Eastern Europe in the 1990s.

    http://www.demographic-research.org/volumes/vol30/64/#ref=rss 2014/06/04 - 21:33
  • BACKGROUNDThe decision about whether to start a family within a partnership can be viewed as a result of an interaction process. The influence of each of the partners in a couple differs depending on their individual preferences and intentions towards having children. Both of the partners additionally influence each other’s fertility intentions and preferences.OBJECTIVEWe specify, estimate, and test a model that examines the decision about whether to have a child as a choice that is made jointly by the two partners. The transition to the birth of a (further) child is investigated with the explicit consideration of both the female partner and the male partner in the partnership context.METHODSAn approach for modelling the interactive influences of the two actors in the decision-making process was proposed. A trivariate distribution consisting of both the female and the male partners’ fertility intentions, as well as the joint generative decision, was modelled. A multivariate non-linear probit model was chosen and the problem of identification in estimating the relative effects of the actors was resolved. These parameters were used to assess the relative importance of each of the partners’ intentions in the decision. We carried out the analysis with MPLUS. Data from the panel of intimate relationships and family dynamics (pairfam) was used to estimate the model.RESULTSThe biographical context of each of the partners in relation to their own as well as to their partner’s fertility intentions was found to be of considerable importance. Of the significant individual and partner effects, the male partner was shown to have the greater influence. But the female partner was found to have stronger parameters overall and she ultimately has a veto power in the couple’s final decision.

    http://www.demographic-research.org/volumes/vol30/63/#ref=rss 2014/06/04 - 21:33
  • OBJECTIVEThis review discusses how biometricians would probably compute or estimate expected waiting times, if they had the data.METHODSOur framework is a time-inhomogeneous Markov multistate model, where all transition hazards are allowed to be time-varying. We assume that the cumulative transition hazards are given. That is, they are either known, as in a simulation, determined by expert guesses, or obtained via some method of statistical estimation. Our basic tool is product integration, which transforms the transition hazards into the matrix of transition probabilities. Product integration enjoys a rich mathematical theory, which has successfully been used to study probabilistic and statistical aspects of multistate models. Our emphasis will be on practical implementation of product integration, which allows us to numerically approximate the transition probabilities. Average state occupation times and other quantities of interest may then be derived from the transition probabilities.

    http://www.demographic-research.org/volumes/vol30/62/#ref=rss 2014/05/29 - 00:10
  • OBJECTIVEThis review discusses how biometricians would probably compute or estimate expected waiting times, if they had the data.METHODSOur framework is a time-inhomogeneous Markov multistate model, where all transition hazards are allowed to be time-varying. We assume that the cumulative transition hazards are given. That is, they are either known, as in a simulation, determined by expert guesses, or obtained via some method of statistical estimation. Our basic tool is product integration, which transforms the transition hazards into the matrix of transition probabilities. Product integration enjoys a rich mathematical theory, which has successfully been used to study probabilistic and statistical aspects of multistate models. Our emphasis will be on practical implementation of product integration, which allows us to numerically approximate the transition probabilities. Average state occupation times and other quantities of interest may then be derived from the transition probabilities.

    http://www.demographic-research.org/volumes/vol30/62/#ref=rss 2014/05/29 - 00:10
  • BACKGROUNDIn this paper we study the long-term consequences of parental divorce in a comparative perspective. Special attention is paid to the heterogeneity of the consequences of divorce for children’s educational attainment by parental education.OBJECTIVEThe study attempts to establish whether the parental breakup penalty for tertiary education attainment varies by socioeconomic background, and whether it depends on the societal context.METHODSData are drawn from the first wave of the Generations and Gender Survey, covering 14 countries. We estimate multi-level random-slope models for the completion of tertiary education.RESULTSThe results show that parental divorce is negatively associated with children’s tertiary education attainment. Across the 14 countries considered in this study, children of separated parents have a probability of achieving a university degree that is on average seven percentage points lower than that of children from intact families. The breakup penalty is stronger for children of highly educated parents, and is independent of the degree of diffusion of divorce. In countries with early selection into educational tracks, divorce appears to have more negative consequences for the children of poorly educated mothers.CONCLUSIONSFor children in most countries, parental divorce is associated with a lower probability of attaining a university degree. The divorce penalty is larger for children with highly educated parents. This equalizing pattern is accentuated in countries with a comprehensive educational system.COMMENTSFuture research on the heterogeneous consequences of parental divorce should address the issue of self-selection into divorce, which might lead to an overestimation of the negative effect of divorce on students with highly educated parents. It should also further investigate the micro mechanisms underlying the divorce penalty.

    http://www.demographic-research.org/volumes/vol30/61/#ref=rss 2014/05/27 - 11:51
  • BACKGROUNDShifting demographic trends in the United States (US) have resulted in increasing numbers of three-generation family households, where a child lives with a parent(s) and grandparent(s). Although similar demographic trends have been occurring in the United Kingdom (UK) and Australia, very little research has studied three-generation coresidence in these countries and no research has documented trends cross-nationally.OBJECTIVEWe investigate differences in the rates of three-generation coresidence in early childhood cross-nationally.METHODSThis study uses three longitudinal birth cohort studies to investigate cross-national differences in three-generation coresidence in early childhood: the Early Childhood Longitudinal Study - Birth Cohort for the US, the Millennium Cohort Study for the UK, and the Longitudinal Study of Australian Children - Birth Cohort.RESULTSWe find that nearly one-quarter of US children live in a three-generation household during early childhood, compared to 8% of children in the UK and 11% in Australia. Although there are large differences in the frequency of coresidence cross-nationally, we find that similar demographic groups live in three-generation households across contexts. In general, younger, less educated, lower income, and minority mothers are more likely to live in three-generation households in all three countries.

    http://www.demographic-research.org/volumes/vol30/60/#ref=rss 2014/05/23 - 20:14
  • BACKGROUNDAs the incidence of cohabitation has been rising in many parts of the world, efforts to determine the forces driving the cohabitation boom have also been intensifying. But most of the analyses of this issue conducted so far were carried out at a national level, and did not account for regional heterogeneity within countries.OBJECTIVEThis paper presents the geography of unmarried cohabitation in the Americas. We offer a large-scale, cross-national perspective, together with small-area estimates of cohabitation. We created this map for several reasons. (i) First, our examination of the geography of cohabitation reveals considerable spatial heterogeneity, and challenges the explanatory frameworks which may work at the international level, but which have low explanatory power with regard to intra-national variation. (ii) Second, we argue that historical pockets of cohabitation can still be identified by examining the current geography of cohabitation. (iii) Finally, our map serves as an initial step in efforts to determine whether the recent increase in cohabitation is an intensification of pre-existing traditions, or whether it has different roots that suggest that a new geography may be evolving.METHODSCensus microdata from 39 countries and 19,000 local units have been pooled together to map the prevalence of cohabitation among women.RESULTSThe results show inter- and intra-national regional contrasts. The highest rates of cohabitation are found in areas of Central America, the Caribbean, Colombia, and Peru. The lowest rates are mainly found in the United States and Mexico. In all of the countries, the spatial autocorrelation statistics indicate that there is substantial spatial heterogeneity.CONCLUSIONSOur results lead us to ask what forces may have shaped these patterns, and they remind us that these forces need to be taken into account when seeking to explain recent cohabitation patterns, and especially the rise in cohabitation.

    http://www.demographic-research.org/volumes/vol30/59/#ref=rss 2014/05/22 - 21:50
  • BACKGROUNDIn survival analysis a large literature using frailty models, or models with unobserved heterogeneity, exists. In the growing literature and modelling on multistate models, this issue is only in its infant phase. Ignoring frailty can, however, produce incorrect results.OBJECTIVEThis paper presents how frailties can be incorporated into multistate models, with an emphasis on semi-Markov multistate models with a mixed proportional hazard structure.METHODSFirst, the aspects of frailty modeling in univariate (proportional hazard, Cox) and multivariate event history models are addressed. The implications of choosing shared or correlated frailty is highlighted. The relevant differences with recurrent events data are covered next. Multistate models are event history models that can have both multivariate and recurrent events. Incorporating frailty in multistate models, therefore, brings all the previously addressed issues together. Assuming a discrete frailty distribution allows for a very general correlation structure among the transition hazards in a multistate model. Although some estimation procedures are covered the emphasis is on conceptual issues.RESULTSThe importance of multistate frailty modeling is illustrated with data on labour market and migration dynamics of recent immigrants to the Netherlands.

    http://www.demographic-research.org/volumes/vol30/58/#ref=rss 2014/05/22 - 21:50
  • BACKGROUNDThe pace of aging is a concept that captures the time-related aspect of aging. It formalizes the idea of a characteristic life span or intrinsic population time scale. In the rapidly developing field of comparative biodemography, measures that account for inter-species differences in life span are needed to compare how species age.OBJECTIVEWe aim to provide a mathematical foundation for the concept of pace. We derive desired mathematical properties of pace measures and suggest candidates which satisfy these properties. Subsequently, we introduce the concept of pace-standardization, which reveals differences in demographic quantities that are not due to pace. Examples and consequences are discussed.CONCLUSIONSMean life span (i.e., life expectancy from birth or from maturity) is intuitively appealing, theoretically justified, and the most appropriate measure of pace. Pace-standardization provides a serviceable method for comparative aging studies to explore differences in demographic patterns of aging across species, and it may considerably alter conclusions about the strength of aging.

    http://www.demographic-research.org/volumes/vol30/57/#ref=rss 2014/05/20 - 19:13
  • BACKGROUNDSome journalists and demographers have asked: How many people have ever been born? What is the fraction F(t) of those ever born up to calendar year t who are alive at t? The conditions under which F(t) rises or falls appear never to have been analyzed.OBJECTIVEWe determine under what conditions F(t) rises or falls.METHODSWe analyze this question in the model-free context of current vital statistics and demographic estimates and in the context of several demographic models.RESULTSAt present F(t) is very probably increasing. Stationary, declining, and exponentially growing population models are incapable of increasing F(t), but a doomsday model and a super-exponential model generate both increasing and decreasing F(t).CONCLUSIONSIf the world's human population reaches stationarity or declines, as many people expect within a century, the presently rising fraction of people ever born who are now alive will begin to fall.COMMENTSIt is curious that nearly all empirical estimates of the number of people ever born assume exponential population growth, which cannot explain increasing F(t).

    http://www.demographic-research.org/volumes/vol30/56/#ref=rss 2014/05/17 - 01:48