Least squares metric,unidimensional unfolding

The partial derivatives of the squared error loss function for the metric unfolding problem have a unique geometry which can be exploited to produce unfolding methods with very desirable properties. This paper details a simple unidimensional unfolding method which uses the geometry of the partial derivatives to find conditional global minima; i.e., one set of points is held fixed and the global minimum is found for the other set. The two sets are then interchanged. The procedure is very robust. It converges to a minimum very quickly from a random or non-random starting configuration and is particularly useful for the analysis of large data sets with missing entries.This paper benefits from many conversations with and suggestions from Howard Rosenthal.     

The right to a decent minimum of health care

Buchanan examines, and finds inadequate, several philosophical approaches to justifying and specifying the content of a universal right to a decent minimum of health care: utilitarian arguments, Rawlsian ideal contract arguments, and Norman Daniels' equality of opportunity argument. Also rejecting the libertarian hypothesis that there is no right to a decent minimum of care, he contends that the claim that society should guarantee certain health care services can be supported by a pluralistic approach encompassing special right-claims, harm prevention, prudential arguments emphasizing public health benefits, and beneficence.     

Why 2 + 2 = 5 looks so wrong: On the odd-even rule in sum verification

The odd-even status of a sum depends on the odd-even status of its addends. A sum must be odd if an odd number of its addends are odd; else it must be even. A proposed sum that violates the required odd-even status of the sum—that is, deviates from the correct sum, whether odd or even, by an odd value (e.g., splits of ±1, ±3, ±5)—can be rejected immediately as false. Subjects in the present study did indeed use the odd-even rule in sum verification, because they were as fast and accurate in rejecting a split of ±1 as one of ±2, and a split of ±3 as one of ±4, even though a larger split generally is easier to reject (symbolic distance effect), and splits of ±3 and ±4 were rejected faster and more accurately than those of ±1 and ±2. Performance on separate odd-even tasks indicated that the odd-even properties of numbers and sums are readily available for use by adults, and that persons who do well on such tasks are especially likely to use the odd-even rule in sum verification.     

Maternal and adolescent depressive symptoms and family conflict: An autoregressive cross-lagged examination of competing models in multi-stressed mothers and adolescents

Maternal and adolescent depression are challenges that often co-occur. Many studies have drawn bivariate associations between maternal depressive symptoms, adolescent depressive symptoms, and family conflict, but few have examined reciprocal effects. Even among extant studies, there is a lack of clarity related to directionality of influence. Three competing theoretical models may explain the relationship between maternal depressive symptoms, adolescent depressive symptoms, and family conflict, and these processes may differ by adolescents’ sex. Using three time points of data from 187 diverse mother-adolescent dyads, we fit a taxonomy of autoregressive cross-lagged structural equation models to simultaneously evaluate the competing theoretical models and also examine differences by sex using multiple-group analyses. Results indicate a symptom-driven model whereby adolescent depressive symptoms predicted increases in family conflict. Sex differences were also found. For males, but not females, greater adolescent depressive symptoms predicted subsequent increases in maternal depressive symptoms, which then predicted lower family conflict—possibly indicating maternal disengagement/withdrawal. Our findings suggest addressing adolescent depressive symptoms in order to prevent family conflict and that distinctive targets for the prevention/intervention of family conflict should account for differences by adolescents’ sex.