Data from the Longitudinal Aging Study Amsterdam were used to study the relationship between neuroticism and aging. At baseline, cross-sectional analyses of data from 2,117 respondents (aged 55-85 years, M = 70) showed no significant age differences. The magnitude of the 3- and 6-year stability coefficients was high, and 12% of the elderly participants showed a clinically relevant mean level ch...

OBJECTIVE National attention has focused on providing health insurance coverage for children. Less awareness has been given to underinsurance, particularly for children with special health care needs (CSHCN). Defined as having inadequate benefits, underinsurance may be a particular problem for CSHCN because of their greater needs for medical care. METHODS We used the 2005-2006 National Survey...

In this article, we investigate clustering methods for multilevel functional data, which consist of repeated random functions observed for a large number of units (e.g., genes) at multiple subunits (e.g., bacteria types). To describe the within- and between variability induced by the hierarchical structure in the data, we take a multilevel functional principal component analysis (MFPCA) approac...

Low birthweight remains a significant public health problem in the United States. Low birthweight (defined as a weight of less than 2500 g at birth for a live-bom infant) has declined very little over the past several decades and is even on the rise among some high-risk groups. ' Much research has focused on individuallevel risk factors for low birthweight; individual-level models, however, hav...

An explosion of new data sources describing historical family composition is opening unprecedented opportunities for discovery and analysis. The new data will allow comparative multilevel analysis of spatial patterns and will support studies of the transformation of living arrangements over the past 200 years. Using measurement methods that assess family choices at the individual level and anal...

The current study disentangled two different effects of wealth on psychological tendency toward independence: one is an effect exerted at the individual level (i.e., being rich) and the other one is a contextual effect (i.e., being surrounded by rich individuals). Past research has found a stronger tendency toward independence among people in economically developed societies. This association h...

Using data from the Longitudinal Study of American Youth (LSAY), the present study examined whether early acceleration of students into formal algebra at the beginning of middle school promoted evident growth in different mathematical areas (basic skills, algebra, geometry, and quantitative literacy) and stable growth across these mathematical areas. Results of multivariate multilevel analyses ...

This longitudinal study examined the extent to which dimensions of infant negative temperament in the first year predicted IQ at age 3, and whether these associations depended on the quality of the infant–mother attachment relationship. In a sample of 63 infant–mother dyads, mothers completed Rothbart's (1981) IBQ when infants were 4 and 12 months, mothers and infants participated in Ainsworth ...