Geburten aus geplanten und ungeplanten Schwangerschaften – Die Relevanz von Bildung,Arbeitslosigkeit und PartnerschaftChildren from Planned and Unplanned Pregnancies: The Importance of Education,Unemployment and Partnership

Micro theories on fertility such as the economic theory of family frame fertility behaviour in industrialized countries as a decision. Predictions of these theories have been tested in numerous empirical studies. This research widely ignores that childbirth may also result from unintended pregnancies. We discuss how education, educational and labour market participation as well as partnership status influence unplanned and planned pregnancy in Germany. To test our hypotheses, we use data from the Socio-Economic Panel Study, collected between 2001 and 2013. The focus is on the planning status of pregnancies leading to a first or third birth. Data on women are analysed with event history models for competing risks. Contrary to arguments of high opportunity costs, graduates show an above-average probability of planned pregnancies. Unemployed women, who should have lower opportunity costs, do not have an increased probability of planned pregnancies; instead their first children are more often unplanned. Consensual unions, which are less serious but offer the same opportunities for sexual activity as marriages, have the highest rate of unplanned pregnancies. The overall findings make clear that future surveys and empirical research might benefit from taking intentions into account, which would enable more rigorous testing of fertility theories.     

Problems related to confidence intervals for impulse responses of autoregressive processes

Confidence intervals for impulse responses computed from autoregressive processes are considered. A detailed analysis of the methods in current use shows that they are not very reliable in some cases. In particular, there are theoretical reasons for them to have actual coverage probabilities which deviate considerably from the nominal level in some situations of practical importance. For a simple case alternative bootstrap methods are proposed which provide correct results asymptotically.     

Computational and statistical efficiency of semiparametric gls estimators

In this note, we report a dramatic improvement in the computational efficiency of semiparametric generalized least squares(SGLS) estimation. Computation of SGLS estimates no longer presents serious problems with data sets of moderate size. We also correct a numerical error in the standard errors of the SGLS estimates reported in our recent paper in this journal (Horowitz and Neumann, 1987). The corrected standard errors of SGLS are comparable to those we reported for quantile estimates.     

The Other‐Race Effect in a Longitudinal Sample of 3‐, 6‐ and 9‐Month‐Old Infants: Evidence of a Training Effect

We investigated the development of the other‐race effect “ORE” in a longitudinal sample of 3‐, 6‐, and 9‐month‐old Caucasian infants. Previous research using cross‐sectional samples has shown an unstable ORE at 3 months, an increase at 6 months and full development at 9 months. In Experiment 1, we tested whether 9‐month‐olds showed the ORE with Caucasian and African faces. As expected, the 9‐month‐olds discriminated faces within their own ethnicity (Caucasian) but not within the unfamiliar ethnicity (African). In months. In Experiment 2, we longitudinally tested infants at 3, 6, and 9 months by presenting either the Caucasian or the African faces used in Experiment 1. In contrast to previous cross‐sectional studies and Experiment 1, we found that infants discriminated between all stimuli. Hence, we did not find the ORE in this longitudinal study even at 9 months. We assume that the infants in our longitudinal study showed no ORE because of previous repetitive exposure to African faces at 3 and 6 months. We argue that only a few presentations of faces from other ethnic categories sufficiently slow the development of the ORE.     

Welfare, labor supply and heterogeneous preferences: evidence for Europe and the US

Following the report of the Stiglitz Commission, measuring and comparing well-being across countries has gained renewed interest. Yet, analyses that go beyond income and incorporate non-market dimensions of welfare most often rely on the assumption of identical preferences to avoid the difficulties related to interpersonal comparisons. In this paper, we suggest an international comparison based on individual welfare rankings that fully retain preference heterogeneity. Focusing on the consumption-leisure trade-off, we estimate discrete choice labor supply models using harmonized microdata for 11 European countries and the US. We retrieve preference heterogeneity within and across countries and analyze several welfare criteria which take into account that differences in income are partly due to differences in tastes. The resulting welfare rankings clearly depend on the normative treatment of preference heterogeneity with alternative metrics. We show that these differences can indeed be explained by estimated preference heterogeneity across countries—rather than demographic composition.     

On difference-based variance estimation in nonparametric regression when the covariate is high dimensional

Summary.  We consider the problem of estimating the noise variance in homoscedastic nonparametric regression models. For low dimensional covariates t  ∈  R ^d ,  d =1, 2, difference-based estimators have been investigated in a series of papers. For a given length of such an estimator, difference schemes which minimize the asymptotic mean-squared error can be computed for d =1 and d =2. However, from numerical studies it is known that for finite sample sizes the performance of these estimators may be deficient owing to a large finite sample bias. We provide theoretical support for these findings. In particular, we show that with increasing dimension d this becomes more drastic. If d 4, these estimators even fail to be consistent. A different class of estimators is discussed which allow better control of the bias and remain consistent when d 4. These estimators are compared numerically with kernel-type estimators (which are asymptotically efficient), and some guidance is given about when their use becomes necessary.     

Planning of medical manpower

The problems of estimating the demand for given professional men within a country is complex and fraught with difficulty. In this paper the authors report on a project in which they faced up to this problem with specific regard to the demands for doctors in Israel in 1982. The results and methodology of the project despite the delimitations expressed in the text should prove interesting to those authorities with similar problems in other countries.     

流动性过剩的测度方法研究

 当前,流动性过剩问题成为中国经济乃至全球经济的一个重要特征，但是在查阅有关文献的同时，我们发现，对于流动性过剩的测度方法缺乏一定的研究。针对这种状况，欧洲中央银行的有关专家提出了四种测度流动性过剩的方法，分别是价格缺口法（price gap,或者称p*法）、真实货币缺口法（real money gap）、名义货币缺口法（nominal money gap）和货币过剩法（money overhang）。我们将这四种方法翻译出来，供大家了解和研究时使用。文章翻译自Thorsten Polleit 和 Dieter Gerdesmeier的《流动性过剩的测度方法》一文，个别部分进行了删节。     

THE GENERALIZED ALCHIAN–ALLEN THEOREM: A SLUTSKY EQUATION FOR RELATIVE DEMAND

We generalize the Alchian–Allen theorem so as to account for income and endowment effects and provide two versions of a Generalized Alchian–Allen theorem: one for a unit cost component and one for a proportional cost component. Both versions provide a decomposition of an uncompensated change in the demand ratio of two goods into a substitution effect and an income‐endowment effect—and may thus be regarded as extensions of the familiar Slutsky equation for relative demand. Finally, we apply our results to the choice of real estates and to parental time allocation decisions, the latter providing implications for child care policies. (JEL D11, H21, J22, R21)