Zur Konstruktion eines adaptiven Persönlichkeitsfragebogens auf Basis eines Konstruktionsrationals

Die vorliegende Arbeit thematisiert die Konstruktion von Persönlichkeitsfragebögen, und stellt eine regelgeleitete Itemkonstruktion als optimale Variante in den Vordergrund. Ziel der Arbeit war – auf Basis eines Konstruktionsrationals – einen Rasch-Modell-konformen Fragebogen zur Messung von Extraversion zu entwickeln, der damit auch zur adaptiven Vorgabe geeignet ist. Im theoretischen Teil der Arbeit wird ein Überblick der Persönlichkeitsmodelle, die Extraversion beinhalten, gegeben. Außerdem wird auf generelle Konstruktionsprinzipien von Fragebögen und auf die probabilistische Testtheorie zur Fragebogenkonstruktion eingegangen. Auf Basis gängiger Definitionen des Konstrukts Extraversion wurde zunächst ein Konstruktionsrational zur regelgeleiteten Itemgenerierung entwickelt. Anschließend wurde damit ein Fragebogen zur Messung von Extraversion entwickelt, welcher als Computerversion an einer Stichprobe von 560 Personen erprobt wurde. Die Analysen des Fragebogens hinsichtlich Rasch-Modell-Konformität ergaben nach dem sukzessiven Ausscheiden von zirka 15% der Items a posteriori Modellgeltung für den verbleibenden Itempool. Um außerdem die Geltung des Konstruktionsrationals zu prüfen, wurde im nächsten Schritt der Rasch-Modell-konforme Itempool mittels des LLTM analysiert, wobei die Strukturmatrizen entsprechend dem Konstruktionsrational definiert wurden. Aufgrund mangelnder Geltung kamen mehrere, schrittweise modifizierte Strukturmatrizen zum Einsatz. Schließlich hielt keine der unterschiedlichen Versionen dem Vergleich mit dem Rasch-Modell stand, was inhaltlich bedeutet, dass die Itemschwierigkeiten nicht hinreichend genau durch das Konstruktionsrational erklärt werden. Die vorliegende Arbeit stellt einen Rasch-Modell-konformen Fragebogen zur Extraversion zur Verfügung – was auch die adaptive Messung dieses Konstrukts ermöglicht

An online experiment on cooperation and groupishness across urban districts

We present experimental evidence that illuminates the trade-off between efficiency considerations and social identity concerns in an inter-city multilevel public goods game. In total, 616 inhabitants of Heidelberg and Mannheim take part in an online experiment in which they can allocate an initial endowment between a private account, an excludable (local) public good, and a non-excludable (regional) public good. We vary the efficiency of the two public goods and find that participants substitute contributions away from the local to the regional public good if the latter is more efficient. To investigate the role of social identity considerations we compare a condition in which the group composition in unknown to a decision in which participants are informed that they share the local public good with three other participants from their own neighborhood. We do not find that a salient common social affiliation affects participants’ behavior per se. If the common local affiliation is revealed through a label, only citizens perceiving a strong local identification adjust their contribution behavior and contribute more to the excludable local public good. Revealing the local affiliation becomes even more effective in a priming condition when participants are remembered of their common local affiliation before they indicate their contribution decision

Classes of depression symptom trajectories in patients with major depression receiving a collaborative care intervention

Purpose Collaborative care is effective in improving symptoms of patients with depression. The aims of this study were to characterize symptom trajectories in patients with major depression during one year of collaborative care and to explore associations between baseline characteristics and symptom trajectories. Methods We conducted a cluster-randomized controlled trial in primary care. The collaborative care intervention comprised case management and behavioral activation. We used the Patient Health Questionnaire-9 (PHQ-9) to assess symptom severity as the primary outcome. Statistical analyses comprised latent growth mixture modeling and a hierarchical binary logistic regression model. Results We included 74 practices and 626 patients (310 intervention and 316 control recipients) at baseline. Based on a minimum of 12 measurement points for each intervention recipient, we identified two latent trajectories, which we labeled \u27fast improvers\u27 (60.5%) and \u27slow improvers\u27 (39.5%). At all measurements after baseline, \u27fast improvers\u27 presented higher PHQ mean values than \u27slow improvers\u27. At baseline, \u27fast improvers\u27 presented fewer physical conditions, higher health-related quality of life, and had made fewer suicide attempts in their history. Conclusions A notable proportion of 39.5% of patients improved only \u27slowly\u27 and probably needed more intense treatment. The third follow-up in month two could well be a sensible time to adjust treatment to support \u27slow improvers\u27. (DIPF/Orig.

Leveling up? An inter-neighborhood experiment on parochialism and the efficiency of multi-level public goods provision

Many public goods can be provided at different spatial levels. Evidence from social identity theory and in-group favoritism raises the possibility that where higher-level provision is more efficient, subjects’ narrow concern for local outcomes (parochialism) could harm efficiency. Building on the experimental paradigm of multi-level public good games and the ‘neighborhood attachment’ concept, we conduct an artefactual field experiment with 600 participants in a setting conducive to parochial behavior. In an inter-neighborhood intra-region design, subjects allocate an endowment between a personal account, a local, and a regional public good account. The between-subjects design varies across two dimensions: One informs subjects that the smaller local group consists of members from their own neighborhood (‘neighbors’). The other varies the relative productivity at the two public goods provision levels. We find evidence for parochialism, but contrary to our hypothesis, parochialism does not interfere with efficiency: The average subject responds to a change in relative productivities at the local and regional level in the same way, whether aware of their neighbors’ presence in the small group or not. The results even hold for subjects with above-median neighborhood attachment and subjects primed on neighborhood attachment

Inter-charity competition under spatial differentiation: sorting, crowding, and spillovers

We study spatially differentiated competition between charities by partnering with two foodbanks in two neighboring cities to conduct a field experiment with roughly 350 donation appeals. We induce spatial differentiation by varying the observability of charities’ location such that each donor faces a socially close ‘home’ and a distant ‘away’ charity. We find that spatially differentiated competition is characterized by sorting, crowding-in, and an absence of spillovers: Donors sort themselves by distance; fundraising (through matching) for one charity raises checkbook giving to that charity, irrespective of distance; but checkbook giving to the unmatched charity is not affected. For lead donors, this implies that the social distance between donors and charities is of limited strategic important. For spatially differentiated charities, matching ‘home’ donations maximizes overall charitable income. Across both charities, however, the additional funds raised fail to cover the cost of the match, despite harnessing social identity for giving

Protein Kinase D: A Selective Target for Antigen Receptors and a Downstream Target for Protein Kinase C in Lymphocytes

Protein kinase Cs (PKCs) are activated by antigen receptors in lymphocytes, but little is known about proximal targets for PKCs in antigen receptor–mediated responses. In this report, we define a role for diacylglycerol-regulated PKC isoforms in controlling the activity of the serine/threonine kinase protein kinase D (PKD; also known as PKCμ) in T cells, B cells, and mast cells. Antigen receptor activation of PKD is a rapid and sustained response that can be seen in T cells activated via the T cell antigen receptor, B cells activated via the B cell antigen receptor, and in mast cells triggered via the high-affinity receptor for IgE (FcεR1). Herein, we show that antigen receptor activation of PKD requires the activity of classical/novel PKCs. Moreover, PKC activity is sufficient to bypass the requirement for antigen receptor signals in the induction of PKD activity. These biochemical and genetic studies establish a role for antigen receptor–regulated PKC enzymes in the control of PKD activity. Regulation of PKD activity through upstream PKCs reveals a signaling network that exists between different members of the PKC superfamily of kinases that can operate to amplify and disseminate antigen receptor signals generated at the plasma membrane

White matter abnormalities in the fornix are linked to cognitive performance in SZ but not in BD disorder: An exploratory analysis with DTI deterministic tractography

Background In psychosis, white matter (WM) microstructural changes have been detected previously; however, direct comparisons of findings between bipolar (BD) and schizophrenia (SZ) patients are scarce. In this study, we employed deterministic tractography to reconstruct WM tracts in BD and SZ patients. Methods Diffusion tensor imaging (DTI) data was carried out with n=32 euthymic BD type I patients, n=26 SZ patients and 30 matched healthy controls. Deterministic tractography using multiple indices of diffusion (fractional anisotropy (FA), tract volume (Vol), tract length (Le) and number of tracts (NofT)) were obtained from the fornix, the cingulum, the anterior thalamic radiation, and the corpus callosum bilaterally. Results We showed widespread WM microstructural changes in SZ, and changes in the corpus callosum, the left cingulum and the fornix in BD. Fornix fiber tracking scores were associated with cognitive performance in SZ, and with age and age at disease onset in the BD patient group. Limitations Although the influence of psychopharmacological drugs as biasing variables on morphological alterations has been discussed for SZ and BD, we did not observe a clear influence of drug exposure on our findings. Conclusions These results confirm the assumption that SZ patients have more severe WM changes than BD patients. The findings also suggest a major role of WM changes in the fornix as important fronto-limbic connections in the etiology of cognitive symptoms in SZ, but not in B