The Wealth and Poverty of Widows: Assets Before and After the Husband's Death

We verify that widows are much more likely than couples to be poor and that they make up a large proportion of the poor elderly; 80 percent are widows or other single individuals. Then we seek to explain why the single elderly are poor, with emphasis on widows. We do this by tracing back over time their financial status, using the Longitudinal Retirement History Survey. The death of the husband very often induces the poverty of the surviving spouse, even though the married couple was not poor. While only about 9 percent of prior couples are poor, approximately 35 percent of the subsequent widows are. A large proportion of the wealth of the couple is lost when the husband dies. In addition we find that: (1) the prior households of poor widows earned and saved less than the prior households of non-poor widows, (2) more of the smaller accumulated wealth was lost at the death of the husband, (3) the absence of survivorship benefits or life insurance insured that the loss in wealth would leave the widow poor thereafter.

Pathways to Disability: Predicting Health Trajectories

The paper considers transitions in the health and disability status of persons as they age. In particular, we explore the relationship between health and disability at younger ages (say 50) and health and disability in future ages. We consider for example, the future health path of persons who are in good health at age 50 compared to the future health path of persons who are in poor health at age 50. To do this, we develop a model that jointly considers health and mortality. The key feature of the model is the assumption of underlying “latent” health that determines both mortality and self-reported responses to categorical health and disability questions. Latent health allows for heterogeneity among individuals and allows for correlation of health status over time, thus allowing for state dependence as well as heterogeneity. The model also allows for classification errors in self-reported response to categorical health and disability questions. All of these are important features of health and disability data, as we show with descriptive data. The model accommodates the strong relationship between self-reported health status and mortality, which is critical to an understanding of the paths of health and disability of the survivors who are observed in panel data files. Our empirical analysis is based on all four cohorts of the Health and Retirement Study (HRS) -- the HRS, AHEAD, CODA and WB cohorts). We find that self-reported health and self-reported disability correspond very closely to one another in the HRS. We find that both self-reported health and disability are strong predictors of mortality. Health and disability at younger ages are strongly related to future health and disability paths of persons as they age. There are important differences in health and disability paths by education level, race, and gender.

Pathways to Disability: Predicting Health Trajectories

The paper considers transitions in the health and disability status of persons as they age. In particular, we explore the relationship between health and disability at younger ages (say 50) and health and disability in future ages. We consider for example, the future health path of persons who are in good health at age 50 compared to the future health path of persons who are in poor health at age 50. To do this, we develop a model that jointly considers health and mortality. The key feature of the model is the assumption of underlying “latent” health that determines both mortality and self-reported responses to categorical health and disability questions. Latent health allows for heterogeneity among individuals and allows for correlation of health status over time, thus allowing for state dependence as well as heterogeneity. The model also allows for classification errors in self-reported response to categorical health and disability questions. All of these are important features of health and disability data, as we show with descriptive data. The model accommodates the strong relationship between self-reported health status and mortality, which is critical to an understanding of the paths of health and disability of the survivors who are observed in panel data files. Our empirical analysis is based on all four cohorts of the Health and Retirement Study (HRS) -- the HRS, AHEAD, CODA and WB cohorts). We find that self-reported health and self-reported disability correspond very closely to one another in the HRS. We find that both self-reported health and disability are strong predictors of mortality. Health and disability at younger ages are strongly related to future health and disability paths of persons as they age. There are important differences in health and disability paths by education level, race, and gender.

What\u27s a Kohoutek?

It was discovered in March of 1973 by Lubos Kohoutek, a German astronomer working at the Hamburg Observatory. The discovery images, on photographic plates taken during an asteroid search, did not indicate the impressive qualities of this travelling space iceberg. It was after 4 weeks of observation that the orbit of this new comet was calculated. The orbit turned out to classify Comet Kohoutek as a member of the sun-grazers

Ab initio calculation of the anomalous Hall conductivity by Wannier interpolation

The intrinsic anomalous Hall effect in ferromagnets depends on subtle spin-orbit-induced effects in the electronic structure, and recent ab-initio studies found that it was necessary to sample the Brillouin zone at millions of k-points to converge the calculation. We present an efficient first-principles approach for computing the anomalous Hall conductivity. We start out by performing a conventional electronic-structure calculation including spin-orbit coupling on a uniform and relatively coarse k-point mesh. From the resulting Bloch states, maximally-localized Wannier functions are constructed which reproduce the ab-initio states up to the Fermi level. The Hamiltonian and position-operator matrix elements, needed to represent the energy bands and Berry curvatures, are then set up between the Wannier orbitals. This completes the first stage of the calculation, whereby the low-energy ab-initio problem is transformed into an effective tight-binding form. The second stage only involves Fourier transforms and unitary transformations of the small matrices set up in the first stage. With these inexpensive operations, the quantities of interest are interpolated onto a dense k-point mesh and used to evaluate the anomalous Hall conductivity as a Brillouin zone integral. The present scheme, which also avoids the cumbersome summation over all unoccupied states in the Kubo formula, is applied to bcc Fe, giving excellent agreement with conventional, less efficient first-principles calculations. Remarkably, we find that more than 99% of the effect can be recovered by keeping a set of terms depending only on the Hamiltonian matrix elements, not on matrix elements of the position operator.Comment: 16 pages, 7 figure