A case of extreme simplicity of the core matrix in three-mode principal components analysis

In three-mode Principal Components Analysis, theP ×Q ×R core matrixG can be transformed to simple structure before it is interpreted. It is well-known that, whenP=QR,G can be transformed to the identity matrix, which implies that all elements become equal to values specified a priori. In the present paper it is shown that, whenP=QR − 1,G can be transformed to have nearly all elements equal to values spectified a priori. A cllsed-form solution for this transformation is offered. Theoretical and practical implications of this simple structure transformation ofG are discussed. Constructive comments from anonymous reviewers are gratefully acknowledged.     

Medical Ethics Research Between Theory and Practice

The main object of criticism of present-day medical ethics is the standard view of the relationship between theory and practice. Medical ethics is more than the application of moral theories and principles, and health care is more than the domain of application of moral theories. Moral theories and principles are necessarily abstract, and therefore fail to take account of the sometimes idiosyncratic reality of clinical work and the actual experiences of practitioners. Suggestions to remedy the illnesses of contemporary medical ethics focus on re-establishing the connection between the internal and external morality of medicine. This article discusses the question how to develop a theoretical perspective on medical ethical issues that connects philosophical reflection with the everyday realities of medical practice. Four steps in a comprehensive approach of medical ethics research are distinguished: (1) examine health care contexts in order to obtain a better understanding of the internal morality of these practices; this requires empirical research; (2) analyze and interpret the external morality governing health care practices; sociological study of prevalent values, norms, and attitudes concerning medical-ethical issues is required; (3) creation of new theoretical perspectives on health care practices; Jensen's theory of healthcare practices will be useful here; (4) develop a new conception of bioethics that illuminates and clarifies the complex interaction between the internal and external morality of health care practices. Hermeneutical ethics can be helpful for integrating the experiences disclosed in the empirical ethical studies, as well as utilizing the insights gained from describing the value-contexts of health care practices. For a critical and normative perspective, hermeneutical ethics has to examine and explain the moral experiences uncovered, in order to understand what they tell us.     

Simplimax: Oblique rotation to an optimal target with simple structure

Factor analysis and principal component analysis are usually followed by simple structure rotations of the loadings. These rotations optimize a certain criterion (e.g., varimax, oblimin), designed to measure the degree of simple structure of the pattern matrix. Simple structure can be considered optimal if a (usually large) number of pattern elements is exactly zero. In the present paper, a class of oblique rotation procedures is proposed to rotate a pattern matrix such that it optimally resembles a matrix which has an exact simple pattern. It is demonstrated that this method can recover relatively complex simple structures where other well-known simple structure rotation techniques fail.This research has been made possible by a fellowship from the Royal Netherlands Academy of Arts and Sciences. The author is obliged to Jos ten Berge for helpful comments on an earlier version.     

The role of analogy in the interpretation of novel compounds

It was investigated whether the on-line interpretative processing of novel nominal compounds is affected by analogous lexicalized compounds. In Experiment 1, novel compounds were presented as nonwords in a lexical decision task. Constituent nouns of novel compounds were of high or low productivity as measured by the number of lexicalized compounds of which they were part. Effects of productivity and of compound interpretability on decision latencies were found to be additive, suggesting that the activated lexicalized compounds do not contribute to the interpretation of novel compounds. In Experiment 2, a semantic priming paradigm was used in a lexical decision task. Lexicalized compounds were presented as targets and novel compounds as primes. Second nouns of lexicalized and novel compounds were identical and first nouns of the two types of compounds were semantically related. Target compounds differed in frequency. Equal priming effects were obtained for high- and low-frequency target compounds, indicating that novel compounds do not activate more strongly the most similar lexicalized compound. The role of analogous interpretative processing is considered in the context of alternative models for the interpretation of novel compounds.     

A numerical approach to the approximate and the exact minimum rank of a covariance matrix

A concept of approximate minimum rank for a covariance matrix is defined, which contains the (exact) minimum rank as a special case. A computational procedure to evaluate the approximate minimum rank is offered. The procedure yields those proper communalities for which the unexplained common variance, ignored in low-rank factor analysis, is minimized. The procedure also permits a numerical determination of the exact minimum rank of a covariance matrix, within limits of computational accuracy. A set of 180 covariance matrices with known or bounded minimum rank was analyzed. The procedure was successful throughout in recovering the desired rank.The authors are obliged to Paul Bekker for stimulating and helpful comments.     

The Effects of Cognitive Training on Brain Network Activity and Connectivity in Aging and Neurodegenerative Diseases: a Systematic Review

Neuropsychology Review - Cognitive training (CT) is an increasingly popular, non-pharmacological intervention for improving cognitive functioning in neurodegenerative diseases and healthy aging....     

Limitations to the spacing effect: demonstration of an inverted u-shaped relationship between interrepetition spacing and free recall

The spacing effect refers to the finding that memory for repeated items improves when the interrepetition interval increases. To explain the spacing effect in free-recall tasks, a two-factor model has been put forward that combines mechanisms of contextual variability and study-phase retrieval (e.g., Raaijmakers, 2003; Verkoeijen, Rikers, & Schmidt, 2004). An important, yet untested, implication of this model is that free recall of repetitions should follow an inverted u-shaped relationship with interrepetition spacing. To demonstrate the suggested relationship an experiment was conducted. Participants studied a word list, consisting of items repeated at different interrepetition intervals, either under incidental or under intentional learn instructions. Subsequently, participants received a free-recall test. The results revealed an inverted u-shaped relationship between free recall and interrepetition spacing in both the incidental-learning condition and the intentional-learning condition. Moreover, for intentionally learned repetitions, the maximum free-recall performance was located at a longer interrepetition interval than for incidentally learned repetitions. These findings are interpreted in terms of the two-factor model of spacing effects in free-recall tasks.     

Homesickness in social context: An ecological momentary assessment study among 1st-year university students

Homesickness is common among university students and associated with mental health problems. Most previous studies assessed homesickness as a summary of the past weeks. However, there may be significant fluctuations across situations. At the current residence, homesickness may especially be triggered during (phone) interactions with attachment figures. Dutch and international 1st-year students (n = 92) completed the Utrecht Homesickness Scale and subsequently used a smartphone application to record social interactions for 14 days (ecological momentary assessment [EMA]). For each interaction they reported the social context (e.g. location, contact type) and their affective state, including homesickness. Homesickness in the past weeks and momentary homesickness were both higher in international students than in Dutch students. Feeling homesick was highest at participants' current residency, when interacting with parents, or when using video-chat. When participants felt more homesick, they reported less pleasant and more unpleasant affect. In conclusion, EMA provided insight in cross-situational variations in homesickness.     

Effectiveness of the ‘Hold me Tight’ Relationship Enhancement Program in a Self‐referred and a Clinician‐referred Sample: An Emotionally Focused Couples Therapy‐Based Approach

While evidence‐based couple therapies are available, only a minority of troubled couples seek help and they often do this too late. To reach more couples earlier, the couple relationship education (CRE) group program “Hold me Tight” (HmT) based on Emotionally Focused Couples Therapy (EFCT) was developed. This study is the first to examine the effectiveness of HmT. Using a three‐wave (waiting period, treatment, and follow‐up) within‐subject design, HmT was delivered to 79 self‐referred couples and 50 clinician‐referred couples. We applied a comprehensive outcome measure battery. Our main findings were that (1) self‐referred couples significantly improved during HmT on all measures, that is relationship satisfaction, security of partner‐bond, forgiveness, daily coordination, maintenance behavior, and psychological complaints, with a moderate‐to‐large mean effect size (d = .63), which was maintained (d = .57) during the 3.5 month follow‐up; (2) in clinician‐referred couples, who were vulnerable in terms of insecure attachment status and psychopathology, the improvement during HmT was moderate (d = .42), but this was reduced during the 3.5‐month follow‐up to a small effect (d = .22); (3) emotional functioning (typical HmT target) as well as behavioral functioning (typical Behavioral Couples Therapy‐based CRE target) improved during HmT; and (4) individual psychological complaints, although not specifically targeted, were reduced during HmT. These findings suggest that HmT is a promising intervention for enhancement of relationship functioning. Clinical implications are discussed.     

Being flexible or rigid in goal-directed behavior: When positive affect implicitly motivates the pursuit of goals or means

Building on previous research on the role of positive affect as implicit motivator we investigated both flexibility and rigidity in goal-directed behavior. Given that goal-directed behavior can be represented in terms of goals or means, we suggest that goal-directed behavior is more flexible in switching means when positive affect implicitly motivates a person to reach the goal, but is more rigid in switching means when positive affect implicitly motivates a person to perform a specific means. Three experiments corroborated this idea: the speed of switching from a learned goal-directed means to a new means was facilitated when positive affect was attached to the representation of the goal, whereas this switching was slowed down when positive affect was attached to the representation of the learned means. Together, these findings provide new insights into the occurrence of flexibility and rigidity in implicitly motivated goal-directed behavior.