Achievement versus aptitude in college admissions: A cautionary note based on evidence from Chile

In recent years there has been a debate over the alleged superiority of achievement tests over aptitude tests on the grounds that the first would be fairer for college admissions and less influenced by family background. The switch from aptitude tests to achievement tests in Chile presented a unique opportunity to examine this claim. Regression analysis was used to assess the impact of the change in test performance using data from seven cohorts of test-takers. The evidence does not support the superiority of achievement tests, particularly when these assess extensive contents.     

String formatting considered harmful for novice programmers

In Java, System.out.printf and String.format consume a specialised kind of string commonly known as a format string. In our study of first-year students at the Ateneo de Manila University, we discovered that format strings present a substantial challenge for novice programmers. Focusing on their first laboratory we found that 8% of all the compilation errors and 100% of the exceptional, run-time behaviour they encountered were due to the improper construction of format strings. Format strings are a language unto themselves embedded within Java, and they are difficult for novice programmers to master when learning to program. In this article, we present exemplars of students' problematic interactions with the Java compiler and run-time environment when dealing with format strings, discuss these interactions, and recommend possible instructional interventions based on our observations.     

Multi-level Discourse Analysis in a Physics Teaching Methods Course from the Psychological Perspective of Activity Theory

In this paper, we present and apply a multi-level method for discourse analysis in science classrooms. This method is based on the structure of human activity (activity, actions, and operations) and it was applied to study a pre-service physics teacher methods course. We argue that such an approach, based on a cultural psychological perspective, affords opportunities for analysts to perform a theoretically based detailed analysis of discourse events. Along with the presentation of analysis, we show and discuss how the articulation of different levels offers interpretative criteria for analyzing instructional conversations. We synthesize the results into a model for a teacher's practice and discuss the implications and possibilities of this approach for the field of discourse analysis in science classrooms. Finally, we reflect on how the development of teachers' understanding of their activity structures can contribute to forms of progressive discourse of science education.     

Near-peer teaching in an anatomy course with a low faculty-to-student ratio

Near-peer teaching is an educational format which utilizes tutors who are more advanced in a curriculum's content to supervise students' activities and to act as instructors in laboratory settings. This format is often used in anatomy laboratory courses. The goal of the present study is to describe the design and implementation of near-peer teaching in an anatomy course and to evaluate students' perceptions of the program. A total of 700 students were registered for this anatomy course which employed near-peer instructors. Of enrolled students, 558 (79.7%) agreed to participate in this study. In general, the practical section (e.g., the clinical hour, image-based anatomy session, and gross anatomy laboratory) of the course was viewed more favorably compared to the theory section (54.8%, n = 306), with dissection and prosection in the laboratory rated as the most valued experiences (34.9%, n = 195). Near-peer teaching is a viable option that satisfies the demands of modern curricula using small groups. This format stimulates learning within courses that have large numbers of students and low faculty-to-student ratios.     

Using matrix norms to estimate the direction of arrival of planar waves on an ULA

SEAD method estimates the direction-of-arrival angles on an uniform linear array based on the difference between the two largest singular values, what is called differential spectrum. Although it presented an outstanding performance, the ability to indicate the source positions was not elucidated yet. Inspired by the differential spectrum formulation we derived a total differential spectrum and found out that the matrix norm induced by the vector 2-norm of a modified spatial covariance matrix can be used to estimate the direction-of-arrival of multiple plane waves. Indeed we show that matrix norms are estimators and we propose their use instead of the singular value decomposition in SEAD-based methods. We present a general mathematical expression in order to explicit the operating principles of the proposed methods. Consequently, we were able to explain how the relation between the arriving and the search angles produces the larger peaks on the differential spectrum. To evaluate the important role played by matrix norms, a thousand experiments were carried out. They showed that the proposed approach proved to be as accurate as the previous SEAD-based methods, while providing a significant reduction on runtime. It also outperformed well-established methods like MODEX regarding the estimation error.     

Parental beliefs about child development and parental inferences about actions during child-rearing episodes

The way parents’ beliefs on child development support the elaboration of practical inferences during everyday child-rearing episodes was examined. We contrasted two models based respectively on the classical and the connectionist view of schema approaches. According to the classical view, parents activate preformed packages of beliefs in order to produce inferences whereas under the connectionist view, they activate the network of interconnected episodic traces that better fits the information provided by the situation. In the former case, the quality of the inferences depends on the activation of the proper schema whereas in the latter case it depends on the structure of the information given. Two experiments were designed in which parents holding a particular global belief about child development (either constructivism or environmentalism), were presented with a target couple with similar or different views with respect to them. In Experiment 1, constructivist parents bearing in mind the couple’s belief had to judge a set of words describing the couple’s image as parents, their educational goals as well as a number of sentences describing the couple’s child-rearing practices during hypothetical episodes. In Experiment 2, environmentalist parents had to judge the couple’s practices and the amount of information presented about the couple’s ideas as well as its plausibility were manipulated. The results indicate that the accuracy and speed in the production of inferences depends on the information presented in the task. When the information is embedded in episodes and a full, plausible and distinctive account of the couple’s belief are provided, then the production of inferences is performed faster and with more accuracy. The results are discussed in terms of the classical and connectionist views of schema approaches.     

Motivation and Commitment to Volunteering in a Sample of Argentinian Adults: What is the Role of Generativity?

This study explores the motivations and commitment to volunteering in a sample of Argentinian adults, and it analyzes the role of generativity. The sample consisted of 200 volunteers who were purposively selected from five volunteer organizations in the city of Córdoba (Argentina). Participants were assigned to three age groups: young volunteers (18–39 years old), middle-aged volunteers (40–59 years old), and older volunteers (60 or plus years old). The motivations of “values” and “understanding” obtained the highest scores. No relevant differences were found between age groups in the motivations and commitment to volunteering. Generative concern showed more predictive value for motivations and commitment to volunteering than any of the sociodemographic variables considered in the study. The results are discussed at the light of considering volunteering as an expression of generativity in different stages of the life cycle.     

Kicking Performance in Young U9 to U20 Soccer Players: Assessment of Velocity and Accuracy Simultaneously

Purpose: The purpose of this study was to compare the kicking performance of young soccer players in the U9 to U20 age groups. Method: Three hundred and sixty-six Brazilian players were evaluated on an official pitch using three-dimensional kinematics to measure (300 Hz) ball velocity (V_ball), foot velocity (V_foot), V_ball/V_foot ratio, last stride length, and distance between the support foot and the ball. Simultaneously, a two-dimensional procedure was also conducted to compute (60 Hz) the mean radial error, bivariate variable error, and accuracy. Possible age-related differences were assessed through one-way analysis of variance and magnitude-based inferences. Results: Ball velocity increased by 103% (p < .001, η² = .39) from the U11 age group (48.54 ± 8.31 km/hr) to the U20 age group (98.74 ± 16.35 km/hr). Foot velocity presented a 59% increase (p < .001, η² = .32) from the U11 age group (49.08 ± 5.16 km/hr) to U20 (78.24 ± 9.49 km/hr). This finding was due to improvement in the quality of foot–ball impact (V_ball/V_foot ratio) from U11 (0.99 ± 0.13 a.u.) to U20 (1.26 ± 0.11 a.u.; p < .001, η² = .25). Parameters such as mean radial error and accuracy appeared to be impaired during the growth spurt (U13–U15). Last stride length was correlated, low to moderately high, with V_ball in all age groups (r = .36–.79). Conclusions: In summary, we concluded that simple biomechanical parameters of kicking performance presented distinct development. These results suggest that different training strategies specific for each age group could be applied. We provide predictive equations to aid coaches in the long-term monitoring process to develop the kick in soccer or search for talented young players.     

Activity of periscapular muscles and its correlation with external oblique during push-up: Does scapular dyskinesis change the electromyographic response?

Scapular dyskinesis is the term used to describe changes in the positioning or movement of the scapula. Such dysfunction is associated with changes in the activation of the scapular muscles. However, the influence of the axial muscles on the scapular muscles activity of subjects with scapular dyskinesis is unknown. This study aimed to compare the electromyography (EMG) activity of periscapular muscles and its correlation with the external oblique muscle during the execution of push-up performed in different surfaces, in volunteers with and without scapular dyskinesis. Thirty-six men, divided in two groups (control and dyskinesis), performed push-up on stable and unstable surface. The EMG activity of serratus anterior (SA_5th and SA_7th fibers), upper (UT) and lower (LT) trapezius, external oblique (EO) was recorded during execution of each task condition. Statistical analyzes were performed using two way ANOVA repeated measures and Pearson correlation. It was observed effect of interaction between factors, being evidenced increased activity of UT, SA_7th and OE for the control group and decreased activity of SA_5th, SA_7th and EO for dyskinesis group during execution of push-up on unstable surface. In both groups positive correlations (r > 0.47) were observed between EMG activity of SA and EO. In the exercises tested, there seems to be an anatomical and functional relationship between the SA and EO muscles. The use of the unstable surface promotes increased neuromuscular demand, but the neuromuscular strategies appear to differ between groups.     

Factors Influencing Scientific Achievements of Medical Students in the Anatomy Research Group: An Analysis From the Autonomous University of Nuevo León in Mexico

Scientific research and student involvement are critical to the formation of physicians, yet the number of medical researchers has decreased over time. To implement corrective strategies, the variables associated with positive research attitudes and productivity among medical students must be identified. The aim of this study was to evaluate the variables associated with students interested or involved in research. A validated questionnaire was applied to the student members of an established anatomy research group in a Mexican medical school with a six-year medical program. Data were collected and analyzed. A total of 85.5% (n = 77/90) students answered the survey with most respondents being second-year medical students. The majority of respondents indicated that the important component of conducting research was a contribution to the new knowledge (45.5%) and to the scientific community (42.9%). More than half of respondents mentioned a professor or a peer as the initial motivation to become involved in research. Lack of time was the main limitation (59.7%) to research involvement. Perceived benefits were knowledge and team work skills. Of those involved, most (85.7%) wished to continue participating in research as a complement to their clinical work. Professors and student colleagues were found to play an important motivational and recruitment role for medical research. These efforts in turn have developed into long-lasting mentor-mentee relationships. Students also anticipated that early involvement in research will positively influence the likelihood of future physicians' contribution and collaboration in research.