A note on computing Louis’ observed information matrix identity for IRT and cognitive diagnostic models

Using Louis’ formula, it is possible to obtain the observed information matrix and the corresponding large-sample standard error estimates after the expectation–maximization (EM) algorithm has converged. However, Louis’ formula is commonly de-emphasized due to its relatively complex integration representation, particularly when studying latent variable models. This paper provides a holistic overview that demonstrates how Louis’ formula can be applied efficiently to item response theory (IRT) models and other popular latent variable models, such as cognitive diagnostic models (CDMs). After presenting the algebraic components required for Louis’ formula, two real data analyses, with accompanying numerical illustrations, are presented. Next, a Monte Carlo simulation is presented to compare the computational efficiency of Louis’ formula with previously existing methods. Results from these presentations suggest that Louis’ formula should be adopted as a standard method when computing the observed information matrix for IRT models and CDMs fitted with the EM algorithm due to its computational efficiency and flexibility.     

I can see myself helping: The effect of self-awareness on prosocial behaviour

Many studies indicate that increasing self-awareness leads to individuals reflecting on their values and ideals (Silvia & Duval, 2001). This self-reflection appears to increase prosocial behaviour (Berkowitz, 1987). However, previously studies typically manipulated self-awareness in situations in which the individual may have felt pressure from the researcher to help. Thus, experimenter pressure to behave prosocially confounds the self-awareness explanation provided in past research. We used a novel experimental paradigm to manipulate self-awareness and remove the researcher's presence to decrease the likelihood that the participant would conform to experimenter demand. Participants were 36 college students (M_age = 19.52; 25 women). The results indicated a strong probability that the experimental condition participants were more prosocial than control condition participants. These findings provide additional support for the hypothesis that self-reflection increases prosocial behaviour, even without experimenter demands. These findings and the importance of studying objective self-awareness in light of the coronavirus are discussed.     

Modeling Asymmetry in the Time–Distance Relation of Ordinal Personality Items

In analyzing responses and response times to personality questionnaire items, models have been proposed which include the so-called “inverted-U effect.” These models predict that response times to personality test items decrease as the latent trait value of a given person gets closer to the attractiveness of an item. Initial studies into these models have focused on dichotomous personality items, and more recently, models for Likert-type scale items have been proposed. In all these models, it is assumed that the inverted-U effect is symmetrical around 0, while, as will be explained in this article, there are substantive and statistical reasons to study this assumption. Therefore, in this article, a general inverted-U model is proposed which accommodates two sources of asymmetry between the response times and the attractiveness of the items. The viability of this model is demonstrated in a simulation study, and the model is applied to the responses and response times of the Temperament and Character Inventory–Revised, covering a broad range of personality dimensions.     

Personal Contact with Refugees is Key to Welcoming Them: An Analysis of Politicians' and Citizens' Attitudes Towards Refugee Integration

Politicians are influential both in directing policies about refugees and in framing public discourse about them. However, unlike other host country residents, politicians' attitudes towards refugees and integration are remarkably understudied. We therefore examine similarities and differences between politicians' attitudes towards refugee integration and those held by citizens. Based on the stereotype content model, we expect that political ideology informs stereotypes about refugees, which subsequently shape attitudes towards refugee integration. Based on the Contact Hypothesis, we further argue that personal contact with refugees reduces negative stereotypes about them—in particular for those endorsing a right-wing ideology. We draw on data collected via two surveys with 905 politicians and 8013 citizens in the Netherlands to show that (1) unlike those with a left-wing orientation, residents (i.e., both politicians and citizens) with a right-wing orientation hold more negative stereotypes about refugees, which in turn relate to more negative attitudes towards refugee integration; (2) personal contact with refugees is associated with less negative stereotypes among residents; and (3) politicians, compared to citizens, report less negative stereotypes and more positive attitudes towards refugee integration. The practical implication of fostering residents' contact with refugees as well as the implications for future research are discussed.     

汉语发展性阅读障碍儿童视觉同时性加工技能子成分的发展及其与阅读的关系

通过分别以高频汉字(实验1)和图形非言语材料(实验2)为刺激的两个联合视觉注意任务, 并采用基于Budensen视觉注意理论的参数估计方法, 系统地探查小学三~六年级汉语发展性阅读障碍儿童的视觉同时性加工技能缺陷的内在机制。以43名汉语发展性阅读障碍儿童和46名生理年龄匹配典型发展儿童为被试, 每类被试均被分为小学中年级组(三、四年级)和高年级组(五、六年级)。两个实验均发现不同年级组的阅读障碍儿童在知觉加工速度参数上显著小于控制组儿童。在空间注意分布权重参数上, 实验1的结果显示, 不同于控制组儿童向左侧化发展的注意分布模式, 两个年级组的阅读障碍儿童均表现为无偏的注意分布; 而实验2未发现显著组别差异。且这两种同时性加工子技能分别与不同水平的汉语阅读技能密切相关。结果表明, 汉语阅读障碍儿童在同时加工多个视觉刺激时存在持续的知觉加工速度缓慢的问题, 在同时加工言语类刺激时还表现出异常的空间注意分布模式。本研究有助于从基础认知层面揭示汉语发展性阅读障碍儿童的缺陷机理, 为进一步设计相关的提高阅读效率的干预方案提供理论依据。     

Single-Stage Prediction Models Do Not Explain the Magnitude of Syntactic Disambiguation Difficulty

The disambiguation of a syntactically ambiguous sentence in favor of a less preferred parse can lead to slower reading at the disambiguation point. This phenomenon, referred to as a garden-path effect, has motivated models in which readers initially maintain only a subset of the possible parses of the sentence, and subsequently require time-consuming reanalysis to reconstruct a discarded parse. A more recent proposal argues that the garden-path effect can be reduced to surprisal arising in a fully parallel parser: words consistent with the initially dispreferred but ultimately correct parse are simply less predictable than those consistent with the incorrect parse. Since predictability has pervasive effects in reading far beyond garden-path sentences, this account, which dispenses with reanalysis mechanisms, is more parsimonious. Crucially, it predicts a linear effect of surprisal: the garden-path effect is expected to be proportional to the difference in word surprisal between the ultimately correct and ultimately incorrect interpretations. To test this prediction, we used recurrent neural network language models to estimate word-by-word surprisal for three temporarily ambiguous constructions. We then estimated the slowdown attributed to each bit of surprisal from human self-paced reading times, and used that quantity to predict syntactic disambiguation difficulty. Surprisal successfully predicted the existence of garden-path effects, but drastically underpredicted their magnitude, and failed to predict their relative severity across constructions. We conclude that a full explanation of syntactic disambiguation difficulty may require recovery mechanisms beyond predictability.     

Looking at remembering: Eye movements,pupil size,and autobiographical memory

To examine the relationship between visual imagery and autobiographical memory, eye position and pupil size were recorded while participants first searched for memories and then reconstructed the retrieved memories (Experiment 1), or only searched for memories (Experiment 2). In Experiment 1, we observed that, although recollective experience was not associated with the number of fixations per minute, memories that took longer to retrieve were linked to increased pupil size. In Experiment 2, we observed that directly retrieved memories were recalled more quickly and were accompanied by smaller pupils than generatively retrieved memories. After correcting for response time, retrieval mode also produced an effect, showing that decreased pupil size is not simply due to directly retrieved memories being recalled more quickly. These findings provide compelling evidence that objective measures, such as pupil size, can be used alongside subjective measures, such as self-reports, to distinguish between directly retrieved and generatively retrieved memories.