Spatial prediction of crystalline defects observed in molecular dynamic simulations of plastic damage

Molecular dynamic computer simulation is an essential tool in materials science to study atomic properties of materials in extreme environments and guide development of new materials. We propose a statistical analysis to emulate simulation output with the ultimate goal of efficiently approximating the computationally intensive simulation. We compare several spatial regression approaches including conditional autoregression (CAR), discrete wavelets transform (DWT), and principle components analysis (PCA). The methods are applied to simulation of copper atoms with twin wall and dislocation loop defects, under varying tilt tension angles. We find that CAR and DWT yield accurate results but fail to capture extreme defects, yet PCA better captures defect structure.     

A social change index-an objective means to discern and measure the relative current social condition of cities,towns, and their sub-communities

A social change index has been developed in response to a social planning need to have a means whereby the current social pathology of communities may be identified on an objective basis. The index is derived from a combination of social indicators which are reported by census tract by the State of Rhode Island on an annual basis. The index is particularly useful for the inter-decennial years because high mobility rates, particularly in central cities (up to 80% in some areas of these cities), cause census data to be unrepresentative in many instances for these years. In addition to serving as a means to identify social needs and problem areas, the index may be used for priority ranking of need for social program services, program monitoring, and program evaluation. The State of Rhode Island is expected to institute a Committee on Social Statistics among whose primary responsibilities will be to encourage state agencies to publish their social statistics by census tracts in their annual reports. It is presumed, consequently, that a larger number of current social indicators will be available to be included in the social change index and increase its accuracy.     

Some aspects of the use of birth expectations data from sample surveys for population projections

The value of national sample survey data relating to birth expectations for projecting births is reassessed in the light of data limitations pointed out by Ryder and Westoff among others and of the methods of projection used by the United States Bureau of the Census. The annual level of fertility under the cohort-fertility projection method depends on the assumptions regarding completed fertility, about which the available survey data are fairly informative, and on the assumptions regarding the timing of births, about which the survey data tell us very little. Test calculations suggest that Ryder and Westoff have overstated the significance of timing relative to completed family size for the level of future births. We believe that the fall in the annual total fertility rate in the first half of the sixties is to be explained only in part by a general delay in childbearing; a moderate to substantial decrease in completed family size has also occurred. Analysis of the latest set of fertility projections of the Census Bureau also suggests that the assumptions about completed fertility are a much more important determinant of the level of future births than timing, both in the short and long term. Although the available expectations data cannot help in predicting short-term annual changes in fertility, they appear useful for making long-term projections of annual fertility. Expansion of the size, frequency, and content of the sample surveys and incorporation of parity and birth interval into the projection method may improve projections.     

Attitudes toward gay,lesbian, and bisexual persons among heterosexual liberal arts college students

This research focuses on attitudes toward homosexuals and homosexuality among 692 heterosexual students at six liberal arts colleges. Attitudes, assessed in a variety of ways, are examined in relation to students' Greek affiliation, sex role attitudes, religion and religiosity, and contact with and knowledge of gays, lesbians, and bisexuals. Results suggest that attributes predicting acceptance of gay, lesbian, and bisexual persons are female sex, liberal sex-role attitudes, lower religiosity as measured both by beliefs and by attendance, membership in more liberal Protestant denominations, attendance at colleges that do not have Greek letter social organizations, and having positive contacts with gay, lesbian, and/or bisexual persons.     

The Relationship between Health Survey and Medical Chart Review Results in a Rural Population

The objective of this study was to understand the relationship between health survey and medical chart based information. The study population consisted of adult patients (17 years of age and older) attending the Bella Coola Medical Clinic who also completed a detailed Health and Quality of Life Survey. A total of 674 adults completed the Health and Quality of Life Survey. Demographically there was excellent agreement between self-report and clinic data for age, sex, height, weight and Aboriginal ancestry. For morbidity, there was excellent agreement between self-reported and clinically recorded diabetes. Good agreement was observed for diagnoses of cancer, heart problems, hypertension, arthritis and breathing problems. Poor agreement was observed for diagnoses of depression, back/neck problems, eye problems, walking problems, stroke, hearing problems and bone/joint problems. There was poor agreement between the number of self-reported and charted clinic visits. Excellent agreement was shown between self-reported height and weight and clinic height and weight. When BMI was calculated good agreement was achieved between self-report and chart data. It can be concluded that the relationship between chart review and self-report health information observed in this rural population is similar to findings from other populations. Researchers who use self-report data on co-morbidity and obesity measures should be aware of possible error in their estimates and how these errors could affect their findings.     

The History and Timing of Depression Onset as Predictors of Young Adult Self‐Esteem

Depression often emerges early in the lifecourse and is consistently shown to be associated with poor self‐esteem. The 3 main objectives of the current study are to (1) evaluate the association between a history major depression and self‐esteem in young adulthood, (2) assess the relationship between timing of depression onset and young adult self‐esteem, and (3) help rule out the alternative interpretation that the relationship between major depression and self‐esteem is due to state dependence bias stemming from recent depressive symptoms and stressful life events. To address these objectives we use data from a 2‐wave panel study based on a community sample of young adults in Miami‐Dade County, Florida (n=1,197). Results indicated that a history of major depression during sensitive periods of social development is associated with negative changes in self‐esteem over a 2‐year period during the transition to young adulthood. Among those with a history of depression, earlier onset was more problematic than later onset for young adult self‐esteem, although the difference disappeared once the level of self‐esteem 2 years prior was controlled. The linkages between the history and timing of depression onset with self‐esteem were observed net of recent depressive symptoms and stressful life events and are thus robust to an alternative interpretation of state dependence. The findings support the argument that major depression, especially if it develops earlier during child‐adolescent development, has negative consequences for one's self‐esteem.     

Relative Risk Aversion: What Do We Know?

The relative risk aversion measure that represents the risk preferences of a decision maker depends on the outcome variable that is used as the argument of the utility function, and on the way that outcome variable is defined or measured. In addition, the relationship between any two such relative risk aversion measures is determined by the relationship between the corresponding outcome variables. These well-known facts are used to adjust several reported estimates of relative risk aversion so that those estimates can be directly compared with one another. After adjustment, the significant variation in the reported relative risk aversion measures for representative decision makers is substantially reduced. JEL Classification: D81     

Greater Downside Risk Aversion

Although investors are concerned foremost with mean and variance, they are also sensitive to downside risk. In this paper, we introduce an index of downside risk aversion to distinguish risk aversion from higher-order aspects of risk preference, including prudence. We show that the index of downside risk aversion S increases with monotonic downside risk averse transformations of utility, thereby directly linking S to the definition of downside risk aversion introduced by Menezes et al. (American Economic Review, 70, 921–932, 1980). Although the index S applies equally to risk averse and risk loving decision makers, for a given positive degree of risk aversion, S is greater when the index of prudence is greater and vice versa.     

CORRELATIONS AND CHARACTERIZATIONS OF THE UNIFORM DISTRIBUTION

Two characterizations of the uniform distribution on a suitable compact space are proved. These characterizations are applied to a number of particular examples of which the most interesting is the following: if X , Y and Z are independent n-vectors whose components are independent and identically distributed within a vector, then the pairwise independence of the product moment correlation coefficients between X , Y and Z implies that these vectors are normally distributed.     

Strange Bedfellows: Deafness,Language, and the Sociology of Knowledge

Most deaf children lack mundane knowledge of the world because of language deprivation and, sometimes, social isolation. Most of these children acquire language late and, therefore, remain longer in the Unwelt (the world of stimuli and physical objects) along with non-symboling animals. This ethnographic study of a State School for the Deaf (SSD) presents a picture of a relatively closed linguistic community and its limited fund of knowledge. Wittgenstein's (1973) aphorism, “The limits of my language mean the limits of my world”, is perfectly realized and illustrated at SSD. Some high school students did not know names for parts of a human face. The findings indicate that deaf children live in a world of “gaps” and “blanks” as they maneuver among a disproportionate number of physical (as opposed to social) objects. Their multiple sign language systems and funds of knowledge are relatively more holistic, concrete, and context-bound than are the language and knowledge systems of their English-speaking counterparts. Education at SSD is more a preparation for life at SSD than it is for life in the outlying economic and high-tech society.