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Experimental findings not suiting the guided search model (GSM) of Cave and Wolfe (1990) and Wolfe (1994) and the modified guided search model (mGSM) of Efron and Yund (1996) are reviewed. Assumptions which explain these discrepancies are added. Thus two possible alternative models are obtained. According to both models the preattentional parallel processing stage of the GSM is related to the right hemisphere, while the attentional stage is related to the left hemisphere. Experiments determining whether one of these models is correct are suggested.

This paper describes the evolution of the design of a mechanical distractor fabricated using additive manufacturing (AM) technology for use in surgical procedures, such as transanal endoscopic microsurgery (TEM). The functionality of the final device was analysed and the suitability of different materials was determined.

Solid modelling and finite element modelling software were used in the design and validation process to allow the fabrication of the device by AM. Several prototypes were manufactured and tested in this study.

A new design was developed to greatly simplify the existing devices used in TEM surgery. The new design is easy to use, more economical and does not require pneumorectum. Different AM materials were investigated with regard to their mechanical properties, orientation of parts in the three-dimensional (3D) printer and cytotoxicity to select the optimal material for the design.

The device designed by AM can be printed anywhere in the world, provided that a 3D printer is available; the 3D printer does not have to be a high-performance printer. This makes surgery more accessible, particularly in low-income regions. Moreover, patient recovery is improved and pneumorectum is not required.

A suitable mechanical distractor was designed for TEM, and different materials were validated for fabrication by AM.

The recent rise in online knowledge repositories and use of formalism for structuring knowledge, such as ontologies, has provided necessary conditions for the emergence of tools for generating knowledge assessment. These tools can be used in a context of interactive computer-assisted assessment (CAA) to provide a cost-effective solution for prompt feedback and increased learner’s engagement. The purpose of this paper is to describe and evaluate a tool developed by the authors, which generates test questions from an arbitrary domain ontology, based on sound pedagogical principles encapsulated in Bloom’s taxonomy.

This paper uses design science as a framework for presenting the research. A total of 5,230 questions were generated from 90 different ontologies and 81 randomly selected questions were evaluated by 8 CAA experts. Data were analysed using descriptive statistics and Kruskal–Wallis test for non-parametric analysis of variance.

In total, 69 per cent of generated questions were found to be useable for tests and 33 per cent to be of medium to high difficulty. Significant differences in quality of generated questions were found across different ontologies, strategies for generating distractors and Bloom’s question levels: the questions testing application of knowledge and the questions using semantic strategies were perceived to be of the highest quality.

The paper extends the current work in the area of automated test generation in three important directions: it introduces an open-source, web-based tool available to other researchers for experimentation purposes; it recommends practical guidelines for development of similar tools; and it proposes a set of criteria and standard format for future evaluation of similar systems.

This paper aims to evaluate and compare the performance of different computer vision algorithms in the context of visual servoing for augmented robot perception and autonomy.

The authors evaluated and compared three different approaches: a feature-based approach, a hybrid approach and a machine-learning-based approach. To evaluate the performance of the approaches, experiments were conducted in a simulated environment using the PyBullet physics simulator. The experiments included different levels of complexity, including different numbers of distractors, varying lighting conditions and highly varied object geometry.

The experimental results showed that the machine-learning-based approach outperformed the other two approaches in terms of accuracy and robustness. The approach could detect and locate objects in complex scenes with high accuracy, even in the presence of distractors and varying lighting conditions. The hybrid approach showed promising results but was less robust to changes in lighting and object appearance. The feature-based approach performed well in simple scenes but struggled in more complex ones.

This paper sheds light on the superiority of a hybrid algorithm that incorporates a deep neural network in a feature detector for image-based visual servoing, which demonstrates stronger robustness in object detection and location against distractors and lighting conditions.

This essay studies disconnections between the macrolevel societal problems of a state and more microlevel political alignments.

Using a dataset composed of macrolevel measures of state problems and microlevel responses to a 2008 election survey, this essay applies multilevel statistical models to explain the state-to-state variance between the states on anti-abortion and pro-gun sentiments. This analysis uncovers the macro- and microlevel factors that disconnect a state’s neglect-of-children indicators from its citizens’ sentiments about abortion, and the factors that disconnect a state’s crime indicators from its citizens’ sentiments about guns.

The initial associations between a state’s indicators of neglect of children and anti-abortion sentiments are explained by the state’s lower human development (HD) and social attributes, especially religious beliefs, which predict social conservatism. The initial associations between a state’s indicators of crime and incarcerations are also explained by a state’s lower HD and the social attributes, especially religious beliefs, which predict social conservatism. Considering both abortion and guns as key indicators of social conservatism, the voters’ political choices exhibit a moralistic axiological rationality rather than a more pragmatic instrumental rationality.

The moral absolutism associated with sentiments about abortion and guns suggests that social conservatism and authoritarianism are intertwined but separate conceptions, which have similar consequences and determinants. Both may be influenced by the same changes in social and educational policies, especially the quality of education.

Approaches to learning have the ability to influence knowledge acquisition, comprehension, retention and even motivation to learn. Previous work indicates that despite age, experience, or prior knowledge, students have a tendency to approach learning differently as a function of the presented content. The purpose of this study is to explore how context influences student approaches to learning science.

The authors adopt a question-asking methodology to evaluate if approaches to learning the same science content vary when presented within the context of Pure Science or the History of Science.

Results indicate that contextualizing the presentation of science content, shifts the approaches students take in attempting to learn science content as evidenced by the questions they ask to deepen their understanding. Additional variables of prior experience with each scientific concept, task persistence at a distractor task and later recall of the presented concepts were related to different inquiry strategies.

Implications for instructional design and pedagogy are discussed.

The framework in which scientific information is presented may impact how students modify existing and create a new schema, impacting their beliefs about scientific knowledge and the way in which students question, hypothesize and engage within the domain of science.

By studying the role of inquiry while students engage in science learning, the authors explore the role of context, content and knowledge retention.

The current study probes at the nature of student questioning and its reliance on the content, context and its relationship to outcome variables such as learning and, perhaps, even persistence as it relates to students’ prior knowledge within content areas which may, in turn, lead to varying levels of student self-efficacy.

This paper aims to examine whether multiple choice questions (MCQs) can be answered correctly without knowing the answer and whether constructed response questions (CRQs) offer more reliable assessment.

The paper presents a critical review of existing research on MCQs, then reports on an experimental study where two objective tests (using MCQs and CRQs) were set for an introductory undergraduate course. To maximise completion, tests were kept short; consequently, differences between individuals’ scores across both tests are examined rather than overall averages and pass rates.

Most students who excelled in the MCQ test did not do so in the CRQ test. Students could do well without necessarily understanding the principles being tested.

Conclusions are limited by the small number of questions in each test and by delivery of the tests at different times. This meant that statistical average data would be too coarse to use, and that some students took one test but not the other. Conclusions concerning CRQs are limited to disciplines where numerical answers or short and constrained text answers are appropriate.

MCQs, while useful in formative assessment, are best avoided for summative assessments. Where appropriate, CRQs should be used instead.

MCQs are commonplace as summative assessments in education and training. Increasing the use of CRQs in place of MCQs should increase the reliability of tests, including those administered in safety-critical areas.

While others have recommended that MCQs should not be used (Hinchliffe 2014, Srivastava et al., 2004) because they are vulnerable to guessing, this paper presents an experimental study designed to demonstrate whether this hypothesis is correct.

The purpose of this paper is to investigate the potential susceptibility of eyewitness memory to the presence of extraneous background speech that comprises a description consistent with, or at odds with, a target face.

A between-participants design was deployed whereby participants viewed an unfamiliar target face in the presence of quiet, or extraneous to-be-ignored speech comprising a verbal description that was either congruent or incongruent with the target face. After a short distractor task, participants were asked to describe the target face and construct a composite of the face using PRO-fit software. Further participants rated the likeness of the composites to the target.

Recall of correct facial descriptors was facilitated by congruent to-be-ignored speech and inhibited by incongruent to-be-ignored speech compared to quiet. Moreover, incorrect facial descriptors were reported more often in the incongruent speech condition compared with the congruent speech and quiet conditions. Composites constructed after exposure to incongruent speech were rated as worse likenesses to the target than those created after exposure to congruent speech and quiet. Whether congruent speech facilitated or impaired composite construction was found to depend on the distinctiveness of the target face.

The results suggest that the nature of to-be-ignored background speech has powerful effects on the accuracy of information verbally reported from having witnessed a face. Incongruent speech appears to disrupt the recognition processes that underpin face construction while congruent speech may have facilitative or detrimental effects on this process, depending on the distinctiveness of the target face.

This is one of the first studies to demonstrate that extraneous speech can produce adverse effects on the recall and recognition of complex visual information: in this case, the appearance of a human face.

To provide educationalists with an understanding of the key quality issues relating to multiple‐choice tests, and a set of guidelines for the quality assurance of such tests.

The discussion of quality issues is structured to reflect the order in which those issues naturally arise. It covers the design of individual multiple‐choice questions, issues relating to the question bank as a whole, choice of test format, and what can be learned through post‐test analysis. The paper offers practical advice, with an emphasis on maximising test reliability.

It is recognised that considerable expertise and effort is required to undertake a thorough post‐test statistical analysis, but pre‐test quality assurance is relatively straightforward, if labour‐intensive. The question of which is best amongst the various alternative test formats is left open.

The general issue of quality assurance of multiple‐choice tests is surely an important one, yet the author is not aware of any other publication that deals directly with this topic.