Assessment and science education: Our essential new priority?

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/92394/1/21033_ftp.pd

An algorithm to compare two‐dimensional footwear outsole images using maximum cliques and speeded‐up robust feature

Footwear examiners are tasked with comparing an outsole impression (Q) left at a crime scene with an impression (K) from a database or from the suspect\u27s shoe. We propose a method for comparing two shoe outsole impressions that relies on robust features (speeded‐up robust feature; SURF) on each impression and aligns them using a maximum clique (MC). After alignment, an algorithm we denote MC‐COMP is used to extract additional features that are then combined into a univariate similarity score using a random forest (RF). We use a database of shoe outsole impressions that includes images from two models of athletic shoes that were purchased new and then worn by study participants for about 6 months. The shoes share class characteristics such as outsole pattern and size, and thus the comparison is challenging. We find that the RF implemented on SURF outperforms other methods recently proposed in the literature in terms of classification precision. In more realistic scenarios where crime scene impressions may be degraded and smudged, the algorithm we propose—denoted MC‐COMP‐SURF—shows the best classification performance by detecting unique features better than other methods. The algorithm can be implemented with the R‐package shoeprintr

NHMRC information paper: evidence on the effectiveness of homeopathy for treating health conditions

This paper provides a summary of evidence from research on the effectiveness of homeopathy in treating health conditions in humans. Findings There was no reliable evidence from research in humans that homeopathy was effective for treating the range of health conditions considered: no good-quality, well-designed studies with enough participants for a meaningful result reported either that homeopathy caused greater health improvements than placebo, or caused health improvements equal to those of another treatment. For some health conditions, studies reported that homeopathy was not more effective than placebo. For other health conditions, there were poor-quality studies that reported homeopathy was more effective than placebo, or as effective as another treatment. However, based on their limitations, those studies were not reliable for making conclusions about whether homeopathy was effective. For the remaining health conditions it was not possible to make any conclusion about whether homeopathy was effective or not, because there was not enough evidence. Conclusions Based on the assessment of the evidence of effectiveness of homeopathy, NHMRC concludes that there are no health conditions for which there is reliable evidence that homeopathy is effective. Homeopathy should not be used to treat health conditions that are chronic, serious, or could become serious. People who choose homeopathy may put their health at risk if they reject or delay treatments for which there is good evidence for safety and effectiveness. People who are considering whether to use homeopathy should first get advice from a registered health practitioner. Those who use homeopathy should tell their health practitioner and should keep taking any prescribed treatments

Guiding explanation construction by children at the entry points of learning progressions

Policy documents in science education suggest that even at the earliest years of formal schooling, students are capable of constructing scientific explanations about focal content. Nonetheless, few research studies provide insights into how to effectively provide scaffolds appropriate for late elementary‐age students' fruitful creation of scientific explanations. This article describes two research studies to address the question, what makes explanation construction difficult for elementary students? The studies were conducted in urban fourth, fifth, and sixth grade classrooms where students were learning science through curricular units that contained 8 weeks of scaffold‐rich activities focused on explanation construction. The first study focused on the kind and amount of information scaffold‐rich assessments provided about young students' abilities to construct explanations under a range of scaffold conditions. Results demonstrated that fifth and sixth grade tests provided strong information about a range of students' abilities to construct explanations under a range of supported conditions. On balance, the fourth grade test did not provide as much information, nor was this test curricular‐sensitive. The second study provided information on pre–post test achievement relative to the amount of curricular intervention utilized over the 8‐week time period with each cohort. Results demonstrated that when taking the amount of the intervention into account, there were strong learning gains in all three grade‐level cohorts. In conjunction with the pre–post study, a type‐of‐error analysis was conducted to better understand the nature of errors among younger students. This analysis revealed that our youngest students generated the most incomplete responses and struggled in particular ways with generating valid evidence. Conclusions emphasize the synergistic value of research studies on scaffold‐rich assessments, curricular scaffolds, and teacher guidance toward a more complete understanding of how to support young students' explanation construction. © 2011 Wiley Periodicals, Inc. J Res Sci Teach 49: 141–165, 2012Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90320/1/20454_ftp.pd

Variaciones en el desarrollo, influencias socioculturales, y dificultades en el aprendizaje de las matemáticas

Es sabido que la mayoría de los niños entran en la escuela con conocimientos y recursos fundacionales para su aprendizaje matemático. Sin embargo, esta no es la historia completa. Resultados de investigaciones revelan enormes diferencias en los niveles de competencia matemática de los niños pequeños, y estas diferencias parecen ser más acusadas en los Estados Unidos que en algunos otros países (por ejemplo, China) (Starkey y Klein, 2008). En este artículo se describen los tipos de diferencias que se dan y se ofrece una revisión sobre lo que se sabe acerca de la naturaleza y las fuentes de las variaciones en el desarrollo entre los niños

Fundamentos cognitivos para la iniciación en el aprendizaje de las matemáticas

En este artículo, sobre fundamentos cognitivos para la iniciación en el aprendizaje de las matemáticas, se realiza una revisión de investigaciones sobre el aprendizaje de las matemáticas en educación infantil. Esta revisión está estructurada según los siguientes apartados: Evidencias sobre la comprensión temprana del número, desarrollo del pensamiento espacial y la geometría, desarrollo de la medición, y regulación de la conducta y la atención

Health communication implications of the perceived meanings of terms used to denote unhealthy foods

Background: Using appropriate terminology in nutrition education programs and behaviour change campaigns is important to optimise the effectiveness of these efforts. To inform future communications on the topic of healthy eating, this study explored adults’ perceptions of the meaning of four terms used to describe unhealthy foods: junk food, snack food, party food, and discretionary food. Methods: Australian adults were recruited to participate in an online survey that included demographic items and open-ended questions relating to perceptions of the four terms. In total, 409 respondents aged 25–64 years completed the survey. Results: ‘Junk food’ was the term most clearly aligned with unhealthiness, and is therefore likely to represent wording that will have salience and relevance to many target audience members. Snack foods were considered to include both healthy and unhealthy food products, and both snack foods and party foods were often described as being consumed in small portions. Despite being used in dietary guidelines, the term ‘discretionary food’ was unfamiliar to many respondents. Conclusions: These results demonstrate that different terms for unhealthy foods can have substantially different meanings for audience members. A detailed understanding of these meanings is needed to ensure that nutrition guidance and health promotion campaigns use appropriate terminology

Contenido matemático fundacional para el aprendizaje en los primeros años

En este capítulo se describe el contenido matemático fundacional accesible para niñas y niños pequeños. El foco en este capítulo está puesto en las propias ideas matemáticas, más que en la enseñanza y el aprendizaje de las mismas. Estas ideas matemáticas se dan por sentadas por los adultos, pero son sorprendentemente profundas y complejas. Hay dos áreas fundamentales en las matemáticas para la primera infancia: (1) el número y (2) la geometría y la medición, tal como identifican los Focos Currículares del NCTM y subrraya este comité. También hay importantes procesos de razonamiento matemático en que los niños deben implicarse. Este capítulo también describe algunas de las conexiones más importantes de las matemáticas infantiles con las matemáticas posteriores

Bridging Physics and Biology Teaching through Modeling

As the frontiers of biology become increasingly interdisciplinary, the physics education community has engaged in ongoing efforts to make physics classes more relevant to life sciences majors. These efforts are complicated by the many apparent differences between these fields, including the types of systems that each studies, the behavior of those systems, the kinds of measurements that each makes, and the role of mathematics in each field. Nonetheless, physics and biology are both sciences that rely on observations and measurements to construct models of the natural world. In the present theoretical article, we propose that efforts to bridge the teaching of these two disciplines must emphasize shared scientific practices, particularly scientific modeling. We define modeling using language common to both disciplines and highlight how an understanding of the modeling process can help reconcile apparent differences between the teaching of physics and biology. We elaborate how models can be used for explanatory, predictive, and functional purposes and present common models from each discipline demonstrating key modeling principles. By framing interdisciplinary teaching in the context of modeling, we aim to bridge physics and biology teaching and to equip students with modeling competencies applicable across any scientific discipline.Comment: 10 pages, 2 figures, 3 table