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Human growth is both a target seeking process regulated by genes and environment, and a highly dynamic process that even under similar social and economic circumstances varies considerably both in amplitude (being short or tall) and tempo (maturing fast or slow). This has led to vivid discussions about which growth chart is the right chart to use. In contrast to wide-spread opinions emphasizing the similarity in early childhood growth among diverse ethnic groups, it has become apparent that a single "global" reference fails to adequately mirror the diversity in human growth. In view of the raising evidence that growth is also influenced by the peer group, we refer to novel, cost-effective procedures that facilitate producing growth references "on demand", for limited regional purposes, for ethnically, socio-economically or politically defined minorities, but also for matching geographically different groups of children and adolescents for international growth and registry studies.

Wiederholungsbefragungen von mehreren Individuen zu wiederkehrenden Zeitpunkten liefern einen reichhaltigen Datenschatz, die sogenannten Paneldaten. Die zweidimensionale Struktur von Paneldaten, bei denen fur eine bestimmte Gruppe von Querschnittseinheiten (dies konnen etwa Personen, Haushalte oder Betriebe sein) interessierende Variablen an mehreren Zeitpunkten erhoben werden, erlaubt die Anwendung reichhaltigerer und realistischerer okonometrischer Spezifikationen als dies bei Verwendung von Querschnitts- oder Zeitreihendaten allein der Fall ware (vgl. z.B. [17]). So ermoglicht die Analyse von Paneldaten unter anderem, unbeobachtete zeitkonstante Unterschiede zwischen den einzelnen Querschnittseinheiten innerhalb des Modells zu kontrollieren. Dies gilt sowohl fur systematische als auch unsystematische Formen solch einer individuenspezifischen Heterogenitat. Bekannte Beispiele fur deutsche Paneldaten sind etwa das Soziookonomische Panel (SOEP), das Nationale Bildungspanel (NEPS) oder das IAB-Betriebspanel. Weitere Beispiele betriebswirtschaftlicher Natur (GfK-Panel) finden sich in Kapitel 19 dieses Buches.

Due to their well-known indeterminacies, factor models require identifying assumptions to guarantee unique parameter estimates. For Bayesian estimation, these identifying assumptions are usually implemented by imposing constraints on certain model parameters. This strategy, however, may result in posterior distributions with shapes that depend on the ordering of cross-sections in the data set. We propose an alternative approach, which relies on a sampler without the usual identifying constraints. Identification is reached ex-post based on a Procrustes transformation. Resulting posterior estimates are ordering invariant and show favorable properties with respect to convergence and statistical as well as numerical accuracy.

Growth and body height have always been topics interesting to the public. In particular, the stupendous increase of some 15-19. cm in final adult height during the last 150 years in most European countries (the " secular trend" ), the concomitant changes in body and head proportions, the tendency towards early onset of sexual maturation, the changes in the age when final height is being reached, and the very recent trend in body mass index, have generated much scientific literature. The marked plasticity of growth in height and weight over time causes problems. Child growth references differ between nations, they tend to quickly become out of date, and raise a number of questions regarding fitting methods, effects caused by selective drop-out, etc. New findings contradict common beliefs about the primary importance of nutritional and health related factors for secular changes in growth. There appears to be a broad age span from mid-childhood to early adolescence that is characterised by a peculiar insusceptibility. Environmental factors that are known to influence growth during this age span appear to have only little or no impact on final height. Major re-arrangements in height occur at an age when puberty has almost been completed and final height has almost been reached, implying that factors, which drive the secular trend in height, are limited to early childhood and late adolescence. © 2010 Elsevier GmbH.

Despite the single currency, yields on government bonds in the Euro Area deviate from German bond yields. These bond spreads are usually attributed to differing default and liquidity risks. Recent research points out that time-varying global factors, approximated by risk measures or short term interest rates, play an important role for the evaluation of theses risks. In this paper, instead of proxy variables latent processes are assumed to model the aforementioned time variation. We find, that default risks measured via expected debt-to-GDP ratio explain a good stake of the variation of bond spreads in the Euro area at least between 2003 and the take-off of the financial crisis. During the financial crisis default risks or rather their evaluation increased but lost relative importance compared to liquidity risks

Several empirical studies are concerned with measuring the effect of currency and current account crises on economic growth. Using different empirical models this paper serves two aspects. It provides an explicit assessment of country specific factors influencing the costs of crises in terms of economic growth and controls via a treatment type model for possible sample selection governing the occurrence of crises in order to estimate the impact on economic growth correctly. The applied empirical models allow for rich intertemporal dependencies via serially correlated errors and capture latent country specific heterogeneity via random coefficients. For accurate estimation of the treatment type model a simulated maximum likelihood approach employing efficient importance sampling is used. The results reveal significant costs in terms of economic growth for both crises. Costs for reversals are linked to country specific variables, while costs for currency crises are not. Furthermore, shocks explaining current account reversals and growth show strong significant positive correlation.

Empirical evidence suggests a sharp volatility decline of the growth in U.S. gross domestic product (GDP) in the mid-1980s. Using Bayesian methods, we analyze whether a volatility reduction can also be detected for the German GDP. Since statistical inference for volatility processes critically depends on the specification of the conditional mean we assume for our volatility analysis different time series models for GDP growth. We find across all specifications evidence for an output stabilization around 1993, after the downturn following the boom associated with the German reunification. However, the different GDP models lead to alternative characterizations of this stabilization : In a linear AR model it shows up as smaller shocks hitting the economy, while regime switching models reveal as further sources for a stabilization, a narrowing gap between growth rates during booms and recessions or flatter trajectories characterizing the GDP growth rates. Furthermore, it appears that the reunification interrupted an output stabilization emerging already around 1987.

In multipurpose surveys, there is often a need for increasing the number of questions in order to assure the coverage of all issues of interest. However, increasing the length of a questionnaire can increase respondent burden, see Sharp and Frankel (1983). This then has possibly a negative influence on the response rate as shown by Marcus, Bosnjak, Lindner, Pilischenko, and Schutz (2007), as well as the quality of the responses, see Herzog and Bachman (1981). One possibility to address this problem is to decrease the length of the questionnaire using multiple matrix sampling design or split questionnaire survey design. The latter, originally developed by Raghunathan and Grizzle (1995) can be considered as an extension of the multiple matrix sampling design described by Shoemaker (1973) and Munger and Loyd (1988). In matrix sampling, every surveyed individual answers a random set of items whereas in the split questionnaire survey design the questionnaire is divided into several components with roughly equal numbers of items, i.e., a core component containing items that are considered to be vitally important (e.g., sociodemographic items) and some split components. Apart from items in the core component, which are inquired of all individuals surveyed, only a fraction of the split components are administered to random subsamples of individuals. Assigning items to split components is based on the correlation coefficients between the items. Items with higher correlations are assigned to different components. Also, the branches of an item and items containing skip patterns are assigned to the same component, because then it can be avoided that items that explaineach other very well are jointly missing for any observation. Following the split questionnaire design each sample individual receives a fraction of the long questionnaire. Data gathered from the whole sample are combined and missing data in the sample caused by the items that are not asked from sample individuals due to split design are completed using multiple imputation as discussed by Rubin (1987), see also Gelman, King, and Liu (1998), Rassler and Koller (2002) and Adiguezel and Wedel (2008).

The association between poverty, malnutrition, illness and poor socioeconomic conditions on the one side, and poor growth and short adult stature on the other side, is well recognized. Yet, the simple assumption by implication that poor growth and short stature result from poor living conditions, should be questioned. Recent evidence on the impact of the social network on adolescent growth and adult height further challenges the traditional concept of growth being a mirror of health. Twenty-nine scientists met at Glücksburg castle, Northern Germany, November 15th - 17th 2013, to discuss genetic, endocrine, mathematical and psychological aspects and related issues, of child and adolescent growth and final height.