算法设计与分析课程中最大子段和问题的教学探讨

介绍算法设计与分析课程中最大子段和问题的动态规划解法,其求解思想是先求给定序列中以每一个元素为尾元素的最大子段和,然后其中的最大者便是整个序列的最大子段和．从两个不同的角度分析最大子段和问题最优解的构造方法,给出最大予段和问题的动态规划算法,并分析算法的时间复杂度。通过这一问题的讲解,有助于学生明确动态规划方法的解题步骤,掌握动态规划算法的设计步骤,     

Transition from high school to university: a person-centered approach to academic achievement

Although a vast body of studies regarding the variables related to students’ achievement exists, only a handful has investigated how these variables combine and interact together. Such an investigation might make it possible to more accurately illustrate the heterogeneity of students enrolling in university and assess the impact of this diversity on academic achievement. The current study focused on the person-centered approach and investigated the possibility of determining significant subgroups of freshmen in the very first week of the academic year in the Belgian educational context. Using k-mean clustering, 2178 freshmen were classified according to their past performance, socioeconomic status, study choice process, and academic self-efficacy beliefs at the beginning of the first year at university. Analyses of variance were also conducted to analyze the relationship between these student clusters and academic achievement outcomes. Six distinct profiles of students were identified representing different combinations of achievement predictors. Results revealed different odds of success among these profiles. The implications of our approach to the understanding of the heterogeneity of freshmen and the first-year achievement process are discussed.     

单因素方差分析中有关统计量的计算

通过列表计算或利用计算器完成单因素试验的方差分析中有关统计量的计算比较麻烦,针对这个问题,根据单因素方差分析的理论,结合列表计算的方法,用Basic语言编写了计算组间平均平方和,误差平均平方和,完成单因素方差分析的程序.利用该程序,计算的工作可以由计算机完成.     

Emotional experiences during test taking: Does cognitive ability make a difference?

This study examined test-related experiences of enjoyment, anger, anxiety, and boredom in a sample of 2059 German school students (50% female) from grade 6, and how they relate to students' abstract reasoning ability (ARA). Emotions were assessed immediately before, during, and after a mathematics achievement test. Analysis of variance showed that emotions experienced during the test situation differed based on students' ARA level, with correspondence analysis revealing substantial differences between the emotional profiles of different ability groups. Enjoyment proved to be most prominent in students with high ARA, whereas anger and anxiety were predominant for students with low ARA. Boredom was found to be highest among students in the intermediate ARA group. Implications for research and practice are discussed.     

Latent profile analysis of students’ reading development and the relation of cognitive variables to reading profiles

Previous studies have showed that early problems with word decoding can lead to poor performance in text reading and comprehension and suggest that poor readers often struggle with reading deficits throughout their school years. Therefore, early detection of those children who are at risk for slow reading development and/or who belong to the lowest reading profiles is essential in order to organize proper support. The present study explores the heterogeneity and prevalence of latent reading profiles among 769 Finnish- and German-reading students during their first and second school years in three countries (Finland, Germany, and Italy) using latent profile analysis. The results identified three latent profiles among Finnish readers, one of which (sentence-level reading) was identified as developing slowly. Among German-reading students, four latent profiles were discovered, two of which were identified as developing slowly. The results of ordinal logistic regression modeling show that rapid automatic naming (RAN) was significantly related to poorer reading profiles among Finnish- and German-reading students, and that the poorer results in letter-sound connection testing among the German-reading group was also significantly related to poorer reading profiles. Although the educational systems have some differences between Germany and German-speaking areas of Italy, no significant country effect was detected. In addition, a child’s age and spoken language did not significantly affect the student’s reading profile.     

Utilizing online learning data to design face-to-face activities in a flipped classroom: a case study of heterogeneous group formation

This study investigates the possibility of utilizing online learning data to design face-to-face activities in a flipped classroom. We focus on heterogeneous group formation for effective collaborative learning. Fifty-three undergraduate students (18 males, 35 females) participated in this study, and 8 students (3 males, 5 females) among them joined post-study interviews. For this study, a total of 6 student characteristics were used: three demographic characteristics obtained from a simple survey and three academic characteristics captured from online learning data. We define three demographic group heterogeneity variables and three academic group heterogeneity variables, where each variable is calculated using the corresponding student characteristic. In this way, each heterogeneity variables represents a degree of diversity within the group. Then, a two-stage hierarchical regression analysis was conducted to identify the significant group heterogeneity variables that influence face-to-face group achievement. The results show that the academic group heterogeneity variables, which were derived from the online learning data, accounted for a significant proportion of the variance in the group achievement when the demographic group heterogeneity variables were controlled. The interviews also reveal that the academic group heterogeneity indeed affected group interaction and learning outcome. These findings highlight that online learning data can be utilized to obtain relevant information for effective face-to-face activity design in a flipped classroom. Based on the results, we discuss the advantages of this data utilization approach and other implications for face-to-face activity design.

     

Exploring the heterogeneity of class in higher education: social and cultural differentiation in Danish university programmes

This paper examines the relationship between social background, choice of university programme and academic culture among Danish university students. Statistically and sociologically, university students are often treated as a homogeneous group, but the ever-increasing number of students in higher education demands a closer examination of the hidden heterogeneity in the students’ social origin and educational strategies. Using a mixed-method approach (register data and ethnographic observations and interviews) the paper focuses on the students’ class origins and on different cultural practices in three Danish university programmes. It is shown that the Danish university field is characterized by a significant variation in social selectivity from programme to programme, and it is argued that these different social profiles correspond with distinctively different cultural practices in the programmes. Correspondingly, the students have distinctively different strategies towards education and future work life.     

Estimating Variance Components from Sparse Data Matrices in Large-Scale Educational Assessments

In generalizability theory studies in large-scale testing contexts, sometimes a facet is very sparsely crossed with the object of measurement. For example, when assessments are scored by human raters, it may not be practical to have every rater score all students. Sometimes the scoring is systematically designed such that the raters are consistently grouped throughout the scoring, so that the data can be analyzed as raters nested within teams. Other times, rater pairs are randomly assigned for each student, such that each rater is paired with many other raters at different times. One possibility for this scenario is to treat the data as if raters were nested within students. Because the raters are not truly independent across all students, the resulting variance components could be somewhat biased. This study illustrates how the bias will tend to be small in large-scale studies.     

The Ethics of Collaboration

Student study teams (SSTs) ideally offer education professionals a means of collaborative, multidisciplinary problem solving to support the academic and behavioral success of students who are at risk for school failure. However, SSTs may in practice not be truly collaborative because they lack an embedded mechanism for group facilitation. This qualitative study investigated how a language-focused consultation approach was used to facilitate the problem identification stage of SSTs in two rural, southern elementary schools. The results indicate that a language-focused consultation affected the SSTs' problem-identification process, which was inhibited by members' use of jargon and slang. This article describes how consultation bridged conceptual gaps between members, scrutinized definitions of jargon and slang, and encouraged collaborative renegotiation of work problems' meanings.     

Jocks,Teckers, and Nerds: The role of the adolescent peer group in the formation and maintenance of secondary school institutional culture

The adolescent peer group constitutes a vital component of the institutional culture of the contemporary secondary school. Formed among students and reinforced by administrators and teachers, it takes the form of a structured status hierarchy whose membership and boundaries are clearly understood within the school community. Individual students' perceptions of their positions within that hierarchy have the potential to impact significantly on their attitudes towards the institution they attend as well as the process of formal education. This study focuses on the attitudes and opinions expressed by 268 students attending two composite secondary schools in a mid‐sized Canadian city, and attempts to provide an insight into an aspect of secondary school education that is not often acknowledged by educators.     

大学生课外时间使用模式及其影响因素分析

时间使用模式不仅是学生日常经验的重要表征,也是本科人才培养与发展的重要影响要素。但时间使用并不单纯是学生理性选择问题,也受制于个人出身背景、组织环境的影响,呈现出群体间的异质性。本研究基于“中国大学生学习与发展追踪研究（CCSS）”2019年数据,利用潜在类别分析和多元逻辑回归方法探讨我国大学生课外时间使用模式及内部异质性。研究发现大学生课外时间使用呈现出“多面高手”“社交达人”和“校园隐士”三种模式;模式的形成受性别、家庭背景、院校类型和年级的影响;不同性别、家庭背景、院校类型和年级的大学生群体中展现出了差异化的时间使用模式特性。时间使用模式有助于我们更清晰地洞察大学生课外经验的典型组织样态;而群体间异质性的时间使用模式也表明了时间作为一项型构兼备结构性和能动性特征,对院校管理者针对性地给予学生支持有重要的指导意义。     

Writing in Mathematics: An Alternative Form of Communication for Academically Low‐Achieving Students

Abstract. Classroom communication figures prominently in current math reform efforts. In this study, we analyze how one teacher used writing to support communication in a seventh‐grade, low‐track mathematics class. For one school year, we studied four low‐achieving students in the class. Students wrote in journals on a weekly basis. Using classroom observations and interviews with the teacher, we developed profiles of the four students, capturing their participation in class discussions. The profiles highlighted an important similarity among the four students: marginal participation in both small‐group and whole‐class discussions. However, our analysis of the students' journals identified multiple instances where the students were able to explain their mathematical reasoning, revealing their conceptual understanding, ability to explain, and skill at representing a problem. In this respect, journals potentially facilitate another important form of classroom communication. The promise of writing is that it offers an alternative to the visions of classroom communication that are strictly oral in nature.     

Performance of student software development teams: the influence of personality and identifying as team members

One prominent approach in the exploration of the variations in project team performance has been to study two components of the aggregate personalities of the team members: conscientiousness and agreeableness. A second line of research, known as self-categorisation theory, argues that identifying as team members and the team's performance norms should substantially influence the team's performance. This paper explores the influence of both these perspectives in university software engineering project teams. Eighty students worked to complete a piece of software in small project teams during 2007 or 2008. To reduce limitations in statistical analysis, Monte Carlo simulation techniques were employed to extrapolate from the results of the original sample to a larger simulated sample (2043 cases, within 319 teams). The results emphasise the importance of taking into account personality (particularly conscientiousness), and both team identification and the team's norm of performance, in order to cultivate higher levels of performance in student software engineering project teams.     

Religiosity,Meaning in Life,and Clinical Symptomology: A Comparison of African-American and European-American College Students

This study examined whether religiosity is subsumed under the broader construct of meaning in life as a predictor of psychological symptomology in college students from two ethnic groups. Data from 299 undergraduates indicated that among European-American students, religiosity predicted little variance in psychological symptomology and was subsumed by general meaning in life. Conversely, for African-American students, perceived meaning in life predicted little variance in symptomology and was subsumed by religiosity. The findings demonstrate that the link between religiosity and mental health among college students differs as a function of ethnic group membership and illustrate the perils of neglecting ethnicity when examining predictors of mental health variables.     

大学生日常管理中的思想与心理教育难题探析

从辅导员工作经验出发,结合在外校走访获取的信息,归纳出新形势下高校学生日常管理中主要的思想和心理教育难题。针对难题,提出破解对策。     

A Sociocultural Analysis of School and Community Settings as Sites for Developing Environmental Practitioners

This article presents analyses of two cultures that emerged from a school/community partnership to develop high school students' competencies as environmental practitioners and serve the needs of a community-based environmental organization. The first culture was situated largely within the school setting, but was linked to the environmental agency through a requirement that students provide service for that organization, which they did primarily through conducting a water quality study to contribute to a watershed management plan. The second culture was situated mostly within the environmental agency itself, and emerged as a group of independent-study students became involved in its daily work. These two activity settings were the units of analysis for delineating salient elements of each culture, and for developing profiles of the types of environmental practitioner identities that were implicit in each. These analyses led to the identification of constraints on students' development within each setting, and then to recommendations for making both cultures more conducive to students' learning and development as environmental practitioners.     

Some Impacts of Science Telecasts

Abstract

The problem investigated in this study was to determine how accurately three related, yet distinct, groups could predict first semester college freshman GPA Data on seventy-six students, parents, and counselors were analyzed.

Correlation coefficients computed between predicted GPA by students, parents, and counselors and GPA actually achieved by the students were found to be 0.5443, 0.6010, and 0.5867 respectively. An analysis of variance of .4265 demonstrated no significant differences between the three groups' predicted GPA. The differences between the students' achieved GPA and the predicted GPA by each group were all significant at the .01 level.

Each group predicted about as well as the more objective measures of academic success; each group tended to predict about the same; and each group tended to over-predict.     

Identification of dysfunctional cooperative learning teams and troubled individuals

In cooperative learning, students work together as a team to maximize the academic success of all the team members. The failure of even a single member can compromise the success of the entire team. Thus, to evaluate the functioning of the team reliably, it is necessary to consider both the performance of the individual team members and the interactions among them. In this study, a method was developed for identifying dysfunctional teams and troubled individuals by examining the correlation between the team scores obtained in sequential tests and the correlation between the scores obtained by the different team members. The effectiveness of the proposed method was evaluated via field experiments. Forty‐eight students were randomly assigned to cooperative learning teams and their learning performance assessed by four‐unit tests. The results indicated that the proposed method can identify the most troubled individuals in a team even when the team performance/grouping information is not taken explicitly into account. Furthermore, when the team information is considered, the method can identify both the dysfunctional teams and the troubled individuals within the teams. Therefore, the proposed method provides a useful basis for the development of computer‐assisted solutions for assessing the performance of cooperative learning teams.