Exploring the Changes in Students’ Understanding of the Scientific Method Using Word Associations

A study is presented that explores how students’ knowledge structures, as related to the scientific method, compare at different student ages. A word association test comprised of ten total stimulus words, among them experiment, science fair, and hypothesis, is used to probe the students’ knowledge structures. Students from grades four, five, and eight, as well as first-year college students were tested to reveal their knowledge structures relating to the scientific method. Younger students were found to have a naïve view of the science process with little understanding of how science relates to the real world. However, students’ conceptions about the scientific process appear to be malleable, with science fairs a potentially strong influencer. The strength of associations between words is observed to change from grade to grade, with younger students placing science fair near the center of their knowledge structure regarding the scientific method, whereas older students conceptualize the scientific method around experiment.     

High School Students’ Perceptions of the Effects of International Science Olympiad on Their STEM Career Aspirations and Twenty-First Century Skill Development

Social cognitive theory guided the design of a survey to investigate high school students’ perceptions of factors affecting their career contemplations and beliefs regarding the influence of their participation in the international Science Olympiad on their subject interests and twenty-first century skills. In addition, gender differences in students’ choice of competition category were studied. Mixed methods analysis of survey returns from 172 Olympiad participants from 31 countries showed that students’ career aspirations were affected most by their teachers, personal interests, and parents, respectively. Students also indicated that they believed that their participation in the Olympiad reinforced their plan to choose a science, technology, engineering, and mathematics (STEM) major at college and assisted them in developing and improving their twenty-first century skills. Furthermore, female students’ responses indicated that their project choices were less likely to be in the engineering category and more likely to be in the environment or energy categories. Findings are discussed in the light of increasing the awareness of the role and importance of Science Olympiads in STEM career choice and finding ways to attract more female students into engineering careers.     

Unequal Division of Type I Risk in Statistical Inferences

Introductory statistics texts give extensive coverage to two‐sided inferences in hypothesis testing, interval estimation, and one‐sided hypothesis tests. Very few discuss the possibility of one‐sided interval estimation at all. Even fewer do so in any detail. Two of the business statistics texts we reviewed mentioned the possibility of dividing the risk of a type I error unequally between the tails for a two‐sided confidence interval. None of the textbooks that were reviewed even considered the possibility of unequal tails for two‐sided hypothesis tests. In this paper, we propose that statistics courses and texts should cover both one‐sided tests and confidence intervals. Furthermore, we propose that coverage, at least in two semesters and advanced courses, should also be given to unequal division of the nominal risk of a type I error for both tests and confidence intervals. Examples are provided for both situations.     

Methodological? Or Dialectical?: Reflections of Scientific Inquiry in Biology Textbooks

International Journal of Science and Mathematics Education - Given the importance of cultivating scientific literate societies, the integration of scientific inquiry into school curriculum is key...     

A five-level static cache architecture for web search engines

Caching is a crucial performance component of large-scale web search engines, as it greatly helps reducing average query response times and query processing workloads on backend search clusters. In this paper, we describe a multi-level static cache architecture that stores five different item types: query results, precomputed scores, posting lists, precomputed intersections of posting lists, and documents. Moreover, we propose a greedy heuristic to prioritize items for caching, based on gains computed by using items’ past access frequencies, estimated computational costs, and storage overheads. This heuristic takes into account the inter-dependency between individual items when making its caching decisions, i.e., after a particular item is cached, gains of all items that are affected by this decision are updated. Our simulations under realistic assumptions reveal that the proposed heuristic performs better than dividing the entire cache space among particular item types at fixed proportions.     

Creative Data in Business Statistics Courses

This paper discusses an innovative approach for using live data generated through student projects or through experiments using student subjects. This live data set, in which the students have a vested interest, becomes the foundation upon which the learning of the statistical concepts is built.