Applications of a computer algebra system in introductory statistics

Maple, a computer algebra system, is employed in introductory statistics courses to promote conceptual learning by students of statistical principles without direct use of mathematics. Maple’s symbolic computation, graphic display, and animation capabilities support an integrated set of procedures for active study of sampling distributions and concepts related to samples, populations, and statistical decision making, error, and power. Students select parameter values for one-line commands and examine the effects of alternatives on computer-generated graphical representations of distributions. The 20 procedures written to support active student exploration of basic statistical concepts are described, and examples of exercises to support their use are provided.     

Attachment Theory and Mindfulness

We initiate a dialog between two central areas in the field of psychology today: attachment theory/research and mindfulness studies. The impact of the early mother-infant relationship on child development has been well established in the literature, with attachment theorists having focused on the correlation between a mother’s capacity for self-regulation and connection (e.g., attunement) with children’s health and developmental outcomes. Because the transition to parenthood is often a stressful one, research has also focused on the importance of the mother’s external and internal support (e.g., self-awareness, recognition of needs) in promoting healthy mother-infant relationships. One promising field in relation to increased internal support is mindfulness, a practice shown to increase emotional regulation while decreasing stress and anxiety. Described as non-judgmental, present-moment awareness, mindfulness has received significant empirical attention over the past three decades and has recently been theorized as an important contributing factor in healthy mother–child relationships. Recognizing the potentially beneficial effects of mindfulness training on healthy attachment, this article reviews relevant literature in presenting a case for exploratory and empirical research into the dynamic relationship between mindfulness, attachment style, maternal health, and children’s development. Grounds for this convergence, as well as suggestions for future research, are presented.     

Preliminary validation of a hope scale for a rare health condition using web-based methodology

An evaluation of a health condition-specific hope scale adapted from the more general dispositional Hope Scale (Snyder et al., 1991) is provided. Participants (N = 202) with a rare, debilitating, and potentially stigmatising health condition were recruited from readers of the Anal Fissure Self Help Page. Data were gathered anonymously using an online survey linked to the website. Consistent with hope theory, this new measure yielded a pathways factor (perceived capacity to find ways to achieve desired goals) and an agency factor (perceived motivation to pursue goals energetically). Respondents with stronger pathways thoughts reported greater benefits from website information for understanding and generating strategies for managing anal fissures. Stronger agency beliefs were related to more frequent website visits, more rereading of first-hand patient accounts, and shorter duration of fissure symptoms. Results offer preliminary support for validity of this scale and for using web-based methodologies to study conditions, such as anal fissure.     

Opposite effects of anxiety and depressive symptoms on executive function: The case of selecting among competing options

People constantly face the need to choose one option from among many, such as when selecting words to express a thought. Selecting between many options can be difficult for anyone, and can feel overwhelming for individuals with elevated anxiety. The current study demonstrates that anxiety is associated with impaired selection across three different verbal tasks, and tests the specificity of this finding to anxiety. Anxiety and depression frequently co-occur; thus, it might be assumed that they would demonstrate similar associations with selection, although they also have distinct profiles of symptoms, neuroanatomy and neurochemistry. Here, we report for the first time that anxiety and depressive symptoms counter-intuitively have opposite effects on selection among competing options. Specifically, whereas anxiety symptoms are associated with impairments in verbal selection, depressive symptoms are associated with better selection performance. Implications for understanding the mechanisms of anxiety, depression and selection are discussed.     

Non-g residuals of the SAT and ACT predict specific abilities

This research examined whether non-g residuals of the SAT and ACT subtests, obtained after removing g, predicted specific abilities. Non-g residuals of the verbal and math subtests of the SAT and ACT were correlated with academic (verbal and math) and non-academic abilities (speed and shop), both based on the Armed Services Vocational Aptitude Battery. Non-g residuals of the SAT and ACT math subtests were positively related to math ability and negatively to verbal ability, whereas the opposite pattern was found for the verbal subtests. Non-g residuals of both sets of subtests were weakly related to non-academic abilities. The results support an investment theory of skills and abilities: Investing in skills in one area (e.g., math) improves abilities in that area but lowers abilities in competing areas (e.g., verbal).     

Nanoscale inclusions in the phonon glass thermoelectric material Zn4Sb3

We have investigated the thermoelectric material Zn₄Sb₃ using transmission electron microscopy (TEM). Nanoscale inclusions with a diameter of about 10 nm were observed, constituting on the order of 1% by volume of the material. Studies using energy filtered imaging, electron diffraction, and high-angle annular dark-field STEM indicate that the inclusions consist of Zn. These inclusions are expected to scatter the medium and long-wavelength phonons effectively, thus contributing to phonon glass behavior which results in the exceptionally low thermal conductivity for this thermoelectric material.