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881.
DeLeire T  Lopoo LM  Simon KI 《Demography》2011,48(2):725-747
Beginning in the mid-1980s and extending through the early to mid-1990s, a substantial number of women and children in the United States gained eligibility for Medicaid through a series of income-based expansions. Using natality data from the National Center for Health Statistics, we estimate fertility responses to these eligibility expansions. We follow Currie and Gruber (2001) and measure changes in state Medicaid-eligibility policy by simulating the fraction of a standard population that would qualify for benefits in different states and different time periods. From 1985 to 1996, the fraction of women aged 15–44 who were eligible for Medicaid coverage for a pregnancy increased more than 20 percentage points. When we use a state and year fixed-effects model with a limited set of covariates, our estimates indicate that fertility increases in response to Medicaid expansions. However, after we include fixed effects for demographic characteristics, the estimated relationship diminishes substantially in size and is no longer statistically significant. We conclude that there is no robust relationship between Medicaid expansions and fertility.  相似文献   
882.
This article decomposes total population momentum into two constituent and multiplicative parts: “nonstable” momentum and “stable” momentum. Nonstable momentum depends on deviations between a population’s current age distribution and its implied stable age distribution. Stable momentum is a function of deviations between a population’s implied stable and stationary age distributions. In general, the factorization of total momentum into the product of nonstable and stable momentum is a very good approximation. The factorization is exact, however, when the current age distribution is stable or when observed fertility is already at replacement. We provide numerical illustrations by calculating nonstable, stable, and total momentum for 176 countries, the world, and its major regions. In short, the article brings together disparate strands of the population momentum literature and shows how the various kinds of momentum fit together into a single unifying framework.  相似文献   
883.
Empirical studies indicate that the transition to parenthood is influenced by an individual’s peer group. To study the mechanisms creating interdependencies across individuals’ transition to parenthood and its timing, we apply an agent-based simulation model. We build a one-sex model and provide agents with three different characteristics: age, intended education, and parity. Agents endogenously form their network based on social closeness. Network members may then influence the agents’ transition to higher parity levels. Our numerical simulations indicate that accounting for social interactions can explain the shift of first-birth probabilities in Austria during the period 1984 to 2004. Moreover, we apply our model to forecast age-specific fertility rates up to 2016.  相似文献   
884.
On April 20, 2005, Connecticut Governor M. Jodi Rell signed into law "An Act Concerning Civil Unions" (Public Act No. 05-10, 2005). That Act did two things: First, it afforded to qualifying same-sex couples many of the rights and benefits that the state makes available to married heterosexual couples. Second, it "defended" heterosexual marriage by defining marriage as involving one man and one woman. Although it might seem that the legislature was moving in an obviously correct direction, its decision to establish a statutory scheme consigning same-sex couples to civil unions was integral to the ideological exclusion of gays and lesbians from marriage and, thereby, implied that they are unfit for family life. The Democrats' and Republicans' focus was on the formal equality guaranteed by the civil union legislation. But the heart of the legislation is disenfranchisement. Connecticut lawmakers placed the stamp of legitimacy on a policy that officially excluded lesbians and gays from full membership in civil society. To many gay and lesbian citizens in Connecticut, it was a slap in the face and awakened a realization that lawmakers' professed egalitarian ideals and the realities of defining who belonged to their communities may not coincide.  相似文献   
885.
This paper examines the relative savings position of migrant households in West Germany paying particular attention to differences between temporary and permanent migrants. Our findings reveal significant differences in the savings rates between German natives and immigrants. If remittances are treated as savings, however, migrants who intend to return to their home country save significantly more than comparable natives. The results of a decomposition analysis indicate that slightly more than half of the differences in the savings rate between Germans and permanent migrants and almost 70% between temporary and permanent migrants can be attributed to differences in observable characteristics.  相似文献   
886.
The optimum growth rate for population under critical-level utilitarianism   总被引:4,自引:2,他引:2  
We characterize optimal consumption, capital, and population growth of a production economy under critical-level utilitarianism. First, we show that neither classical utilitarianism nor average utilitarianism can avoid a corner solution for the population growth rate, in that under the former, population grows at the maximum speed (the so-called repugnant conclusion) while under the latter, it grows at the minimum. Second, we show that critical level utilitarianism yields an interior solution for the population growth rate provided the critical level belongs to a positive, open interval. Finally, we characterize the transition to the steady state and perform comparative dynamics analysis.  相似文献   
887.
888.
889.
One of the cornerstones of any non-inferiority trial is the choice of the non-inferiority margin delta. This threshold of clinical relevance is very difficult to determine, and in practice, delta is often "negotiated" between the sponsor of the trial and the regulatory agencies. However, for patient reported, or more precisely patient observed outcomes, the patients' minimal clinically important difference (MCID) can be determined empirically by relating the treatment effect, for example, a change on a 100-mm visual analogue scale, to the patient's satisfaction with the change. This MCID can then be used to define delta. We used an anchor-based approach with non-parametric discriminant analysis and ROC analysis and a distribution-based approach with Norman's half standard deviation rule to determine delta in three examples endometriosis-related pelvic pain measured on a 100-mm visual analogue scale, facial acne measured by lesion counts, and hot flush counts. For each of these examples, all three methods yielded quite similar results. In two of the cases, the empirically derived MCIDs were smaller or similar of deltas used before in non-inferiority trials, and in the third case, the empirically derived MCID was used to derive a responder definition that was accepted by the FDA. In conclusion, for patient-observed endpoints, the delta can be derived empirically. In our view, this is a better approach than that of asking the clinician for a "nice round number" for delta, such as 10, 50%, π, e, or i.  相似文献   
890.
夏乐平 《人口研究》2005,29(4):2-15
本文研究中国从1979年开始提倡一对夫妇只生育一个孩子至2000年第五次人口普查的生育趋势。为此目的,本文对1979~2001年各生育调查数据与国家统计局每年人口变动调查数据进行比较研究。四普、五普的回推数据,中国国家人口计生委报表中的出生数据和公安部户籍中的出生登记也作为比较对象。鉴于材料中的矛盾,本文就分析教育部部门统计中的各种和出生数据有间接关系的记载、讨论它们内在的口径问题和它们所涉及到的工作程序问题。本文在这一基础上用小学在校学龄儿童年龄分组的数据来估计中国1979~1997年的生育水平和其他资料的可靠性。分析暗示出生数据漏报问题普偏存在,自教育数据算出来的生育数据比许多其他资料高。虽然如此,但自1996年以来比国家统计局的修正数字低。结果同时表明,中国1992年以来确实达到了低生育水平。根据教育统计资料计算的1997年的总和生育率为1·6左右。  相似文献   
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