Using Interpretable Machine Learning for Differential Item Functioning Detection in Psychometric Tests.

This study presents a novel method to investigate test fairness and differential item functioning combining psychometrics and machine learning. Test unfairness manifests itself in systematic and demographically imbalanced influences of confounding constructs on residual variances in psychometric modeling. Our method aims to account for resulting complex relationships between response patterns and demographic attributes. Specifically, it measures the importance of individual test items, and latent ability scores in comparison to a random baseline variable when predicting demographic characteristics. We conducted a simulation study to examine the functionality of our method under various conditions such as linear and complex impact, unfairness and varying number of factors, unfair items, and varying test length. We found that our method detects unfair items as reliably as Mantel-Haenszel statistics or logistic regression analyses but generalizes to multidimensional scales in a straight forward manner. To apply the method, we used random forests to predict migration backgrounds from ability scores and single items of an elementary school reading comprehension test. One item was found to be unfair according to all proposed decision criteria. Further analysis of the item's content provided plausible explanations for this finding. Analysis code is available at: https://osf.io/s57rw/?view_only=47a3564028d64758982730c6d9c6c547.

Neural responses to acute stress predict chronic stress perception in daily life over 13 months.

The importance of amygdala, hippocampus, and medial prefrontal cortex (mPFC) for the integration of neural, endocrine, and affective stress processing was shown in healthy participants and patients with stress-related disorders. The present manuscript which reports on one study-arm of the LawSTRESS project, aimed at investigating the predictive value of acute stress responses in these regions for biopsychological consequences of chronic stress in daily life. The LawSTRESS project examined law students either in preparation for their first state examination (stress group [SG]) or in the mid-phase of their study program (control group [CG]) over 13 months. Ambulatory assessments comprising perceived stress measurements and the cortisol awakening response (CAR) were administered on six sampling points (t1 = - 1 year, t2 = - 3 months, t3 = - 1 week, t4 = exam, t5 = + 1 week, t6 = + 1 month). In a subsample of 124 participants (SG: 61; CG: 63), ScanSTRESS was applied at baseline. In the SG but not in the CG, amygdala, hippocampus, and (post-hoc analyzed) right mPFC activation changes during ScanSTRESS were significantly associated with the trajectory of perceived stress but not with the CAR. Consistent with our finding in the total LawSTRESS sample, a significant increase in perceived stress and a blunted CAR over time could be detected in the SG only. Our findings suggest that more pronounced activation decreases of amygdala, hippocampus, and mPFC in response to acute psychosocial stress at baseline were related to a more pronounced increase of stress in daily life over the following year.

Daily life stress and the cortisol awakening response over a 13-months stress period - Findings from the LawSTRESS project.

The LawSTRESS project is a controlled prospective-longitudinal study on psychological, endocrine, central nervous and genetic predictors of responses to long-lasting academic stress in a homogenous cohort. In this first project report, we focused on the association between daily life stress and the cortisol awakening response (CAR). The CAR, a distinct cortisol rise in the first 30-45 min after morning awakening, is a well-established marker of cortisol regulation in psychoneuroendocrinology. Law students from Bavarian universities (total n = 452) have been studied over a 13-months period at six sampling points starting 12 months prior exam. The stress group (SG) consisted of students experiencing a long-lasting and significant stress period, namely the preparation for the first state examination for law students. Law students assigned to the control group (CG) were studied over an equally long period without particular and sustained stress exposure. To investigate stress related alterations in the CAR, we examined a subsample of the LawSTRESS project consisting of 204 students with 97 participants from the SG (69.1% female, mean age = 22.84 ± 1.82) and 107 from the CG (78.5% female, mean age = 20.95 ± 1.93). At each sampling point, saliva samples for cortisol assessment were collected immediately upon awakening and 30 as well as 45 min later. Perceived stress in daily life was measured by repeated ambulatory assessments (about 100 queries over six sampling points). The time course of perceived stress levels in the two groups differed significantly, with the SG showing an increase in perceived stress until the exam and a decrease thereafter. Stress levels in the CG were relatively stable. The CAR was not significantly different between groups at baseline. However, a blunted CAR in the SG compared to the baseline measure and to the CG developed over the measurement timepoints and reached significance during the exam. Remarkably, this effect was neither associated with the increase in perceived stress nor with anxiety and depression symptoms, test anxiety and chronic stress at baseline. The present study successfully assessed multidimensional stress trajectories over 13 months and it documented the significant burden, law students preparing for the first state examination are exposed to. This period was related to a blunted CAR with presumed physiological consequences (e.g., on energy metabolism and immune function). Mean psychological stress levels as well as the CAR returned to baseline levels after the exam, suggesting a fast recovery in the majority of the participants.

Family formation trajectories across borders: A sequence analysis approach to Senegalese migrants in Europe.

This article examines the relationship between the timing of international migration and family formation trajectories (union formation and fertility) of Sub-Saharan African migrants in Europe. Longitudinal life-history data from Senegalese migrants in France, Italy and Spain, collected as part of the Migrations between Africa and Europe (MAFE) project are used. Applying sequence analysis techniques and distinguishing between men and women, individuals are grouped into different clusters according to the (dis-)similarities in their family formation trajectories before and after migration. Furthermore, multinomial logistic regression models are used to test associations between individual and contextual characteristics and the obtained clusters. The results show important differences between men and women regarding their migration-family formation trajectories. Moreover, the interrelatedness of family and migration events was more pronounced among women than men. The regression analysis indicates that male and female trajectories are related in particular to age and the country of destination, but there are also differences by educational level. The findings stress the importance of differentiating between men and women when studying the family formation behavior of migrants.

Peer teaching beyond the formal medical curriculum.

Peer-assisted learning (PAL) is nowadays commonly implemented in medical education. Mostly PAL is utilized to specifically support teaching within one subject or a specific curricular situation. Here, we present a large-scale peer teaching program that aims to address the individual student's learning needs. In addition, it provides a platform for students to participate in academic teaching. A retrospective data analysis was performed to reveal the program's development and acceptance. The program was implemented in 2008/09 with three tutorials conducted by 24 student tutors to support students preparing for reexaminations. Since then, the program has continuously grown. In 2015/16, 140 tutors conducted 52 tutorials, consisting of 2,750 lessons for 1,938 tutees. New tutorial categories were continuously introduced. In 2015/16, these encompassed tutorials that were held concomitantly to the formal curriculum, tutorials that exceeded the contents of the formal curriculum, tutorials for preparation for the state examination, and electives. Evaluations among the tutees revealed that 93.5% of the respondents rated the courses overall as "good" or "excellent" ( n = 13,489) in 2015/16. All elements of the peer teaching program are managed by one academic group. This encompasses the organization of tutorials, the quality management, and the qualification of tutors, including content-related supervision and didactic training. We conclude that the implementation of a large-scale peer teaching program can complement the formal curriculum. This might be beneficial for both tutors who can actively train their didactic and content-related competencies, and tutees who can autonomously consolidate and expand their knowledge.

Does Migrant Background Matter for Adolescents' Fertility Preferences? The Latin American 1.5 Generation in Spain.

This article examines the fertility preferences of Latin American adolescents of the 1.5 generation and their native peers in Spain. We compare their expected age at first birth as well as their expected family size. The fertility preferences of the 1.5 generation are likely to reflect the family values of two different socialization environments as well as the adaptation process to the childbearing norms of the host society. The analysis is based on the Chances Survey, which collected data from 2700 adolescents in secondary schools in Madrid in 2011. Results indicate that fertility timing preferences of Latin American adolescents reflect socialization influences from the society of origin, but also a quick adaptation to the childbearing norms in the host society, since their expected age at first birth is somewhat earlier than that of their Spanish peers but considerably later than that prevailing in their country of origin. The degree of social integration, measured by the number of the respondent's best friends who were Spanish, seems more important than age at migration for diminishing the gap between Latin Americans and Spaniards. Moreover, higher educational expectations are associated with preferences for postponed entry into parenthood. With regard to family size expectations, we find no significant variation between adolescents of migrant and native origin, confirming the argument that the "two-child norm" currently prevails in both middle- and high-income countries.