Structural Determinants of Infant Mortality in Metropolitan and Nonmetropolitan America1

Abstract A conceptual model of the impact of structural advantage and disadvantage on infant mortality rates is developed and fitted to countylevel data. This model includes mediating endogenous constructs representing medical care availability, the incidence of teenage childbearing, and low birthweight rates and is estimated for three residence categories. Both direct and indirect effects of social structure and teenage childbearing on infant mortality vary significantly across the categories. Structural advantage exerts a significant and negative direct effect on infant mortality rates in urban areas, but in rural areas this effect is indirect, operating through teenage childbearing and low birthweight. Structural disadvantage significantly increases infant mortality in both rural and urban settings, but the effects operate directly in metropolitan areas and indirectly in rural areas. These results underscore the central role that social structure continues to play in determining infant mortality rates in the United States.     

Sampling and estimation in large social networks

An unknown network is modelled by a directed or undirected graph having vertices of different kinds. Partial information is available concerning the vertex labels and the edge occurrences within a simple random sample of vertices. Using this information we find unbiased estimators and variance estimators of such graph parameters which can be given as dyad or triad counts. In particular, we give approximate formulae pertaining to large networks.     

Brain of Britain: brain or chance?

The paper describes a simulation of the popular BBC Radio general knowledge quiz 'Brain of Britain'. The relative levels of knowledge of the 64 contestants in any annual competition are selected from an appropriate distribution and ranked accordingly. The relative difficulties of the questions are selected from three distributions in accordance with the deliberate intentions of the question-setter. By Monte Carlo simulation of the complete annual quiz the relationship between a contestant's rank and his fortune has been established.

The best contestant is found to have only a 20% probability of becoming 'Brain of Britain'. Nevertheless it is demonstrated that there are no practicable modifications to the quiz format which would result in any worthwhile improvement.     

Developing measures of perceived life quality: Results from several national surveys

This report presents the current status of a series of studies oriented toward the assessment of perceived life quality. The conceptual model proposes that a person's overall sense of life quality is understandable as a combination of affective responses to life ‘domains’, which are of two types-role situations and values. Over 100 items used to measure a wide variety of domains and 28 items assessing perceived overall life quality are presented. Various subsets of these items were used in interviews with several representative samples of American adults. Based on these data the domain items were grouped into a smaller number of semi-independent clusters which were internally stable across 10 different subgroups of the respondents and whose interrelationships were highly replicable in independent national samples. A series of analyses, some replicated in more than one survey showed: (1) an additive combination of 12 selected domains explained 50–60% of the variance in an index of overall life quality, (2) neither other domains nor several social characteristic variables contributed additional explanatory power, (3) this level of explanation was achieved in each of 22 subgroups of the population, and (4) additive combinations of domains worked as well as more complicated combinations.