A dynamic decision model for portfolio investment and assets management

This paper addresses a dynamic portfolio investment problem. It discusses how we can dynamically choose candidate assets, achieve the possible maximum revenue and reduce the risk to the minimum level. The paper generalizes Markowitz's portfolio selection theory and Sharpe's rule for investment decision. An analytical solution is presented to show how an institutional or individual investor can combine Markowitz's portfolio selection theory, generalized Sharpe's rule and Value-at-Risk(VaR) to find candidate assets and optimal level of position sizes for investment (dis-investment). The result shows that the generalized Markowitz's portfolio selection theory and generalized Sharpe's rule improve decision making for investment.     

Characteristics of students who benefit from high-quality mathematics instruction

The present study examined characteristics of students who took advantage of the opportunity to learn Algebra II from a highly skilled teacher. In particular, student information was gathered concerning: (a) the amount of mathematics students knew prior to the class, (b) their motivation for learning mathematics, (c) the number and types of interactions they had with the teacher during class, (d) degree of self-regulation, and (e) general aptitude. A model for achievement was used that suggests both opportunity and propensity are important (i.e., students must be willing and able to take advantage of opportunity). Support for the model was found. Propensity to take advantage of a highly favorable opportunity accounted for almost sixty percent of the variance in achievement. In particular, students who were self-regulated, had strong mathematics backgrounds, and had low levels of frustration benefited more from high-quality instruction.     

Using Variables in School Mathematics: Do School Mathematics Curricula Provide Support for Teachers?

This study employed content analysis to examine 3 popular middle-grades mathematics curricula in the USA on the support they provide for teachers to implement concepts associated with variables in school mathematics. The results indicate that each of the 3 curricula provides some type of support for teachers, but in a varied amount and quality. More specifically, whereas the University of Chicago School Mathematics Project (UCSMP) curriculum provides support for teachers on several aspects of using variables in school mathematics, the support found in the Connected Mathematics 2 and the Math Connects curricula focused mainly on one conception of variables—namely, the use of variables as quantity that varies in the Connected Mathematics 2 curriculum and the use of variables as specific unknowns in the Math Connects curriculum. Overall, the UCSMP curriculum provides the most support for teachers, followed by the Connected Mathematics 2 curriculum, with the Math Connects curriculum recording the least support for teachers to enact variable concepts. It is worth pointing out that, although the 3 curricula collectively provide guidance for teachers to implement variable ideas within meaningful real-world contexts, the supports identified in the respective curriculum were not sufficient in addressing all of the areas that are essential for teaching the many concepts associated with variables in school mathematics effectively. Recommendations for curriculum developers and for international researchers with interest in the roles of variables in school mathematics are provided.     

Temperament, emotion, and social interactive behavior in the strange situation: a component process analysis of attachment system functioning

This study examines the contributions of temperamentally and nontemperamentally based emotional reactions to the organization of social interactive behavior within the Strange Situation to better understand the emotional underpinnings of attachment system functioning. At 12 1/2 and 19 1/2 months, temperamental fear (assessed via maternal report) was related to independent per-episode dimensions of social interactive and distress behavior. Fear was moderately correlated with both distress and interactive dimensions at each age. Path-analytic models revealed that temperamental fear had direct effects on interactive behavior and also indirect effects mediated by preceding distress reactions. However, residualized measures of "context-specific" distress (with temperamental variance removed) were still highly consistent across Strange Situation episodes and also significantly predicted subsequent social interactive behavior; furthermore, stable distress reactions from 12 1/2 to 19 1/2 months significantly predicted concurrent stability in social interactive behavior. We discuss likely sources of "context-specific" emotional influences on Strange Situation behavior and also age-related differences in these findings.     

Car Capers

你关注过路上有趣的车牌吗？数字、字母、个性车牌。它们或许都有着不为我们所知的特殊含义。     

Gender Adeptness Among Educational Administrators for Leading Innovative Initiatives in Public Education

It may be concluded that female administrators are perceived as being more adept than their male counterparts for leading innovation in schools and leveraging resources into productive outputs. It may be concluded that both genders of administrators perceive such efforts similarly. The only two skills where gender is significant are the two eornpetencies identified as being alert for new opportunities and synthesizing ideas into focused projects. For the other eight skills indicated in the survey, gender did not play a significant role in such perceptions.     

Rehabilitation and Non-Rehabilitation Counselor Candidates: Comparison of Interview Behavior and Personality Techniques

This study investigated the hypothesis that conventional role stereotypes of rehabilitation and non-rehabilitation counselors attract counselor candidates who differ in preferred modes of counseling interview behavior and in personality characteristics. Twenty-four rehabilitation counselor candidates and 21 non-rehabilitation counselor candidates enrolled in a beginning counseling course held interviews with a standard client. Candidates' responses were classified employing a content analysis scale. All subjects had taken the 16 PF at the beginning of the course. Results found rehabilitation counselor candidates used informative, questioning, diagnosing, and probing responses more frequently and feeling responses less frequently than did non-rehabilitation candidates. Non-rehabilitation candidates appeared less practical, conservative, and group adherent on the 16 PF than rehabilitation candidates.     

Patterns of Social Interaction of Mainstreamed Preschool Children: Hopeful News from the Field

Much of the research on social interaction in mainstreamed settings has focused on “reverse mainstreamed” or special environments in contrast, the present study observed 600 social interactions in 19 regular preschools. Three findings emerged: a) retarded children are substantially integrated into the emotional and social life of the peer group, but not fully integrated into peer group verbal life; b) there is an inverse relationship between teachers’ initiation of social interaction with retarded children and the degree to which the latter are integrated into peer group life; and c) teachers provide retarded children with more verbal enrichment and emotional protection than these children receive from their peer group. On balance, these findings are fairly encouraging, suggesting that to a considerable extent mainstreaming is working in preschool classrooms.     

Mirror-image stimulation and short separations in stumptail monkeys

Two experiments examined the responses of infant stumptail macaques (Macaco arctoides) to mirror-image stimulation (MIS) during short social separations. Overall, infants living in pairs showed agitation when separated from their partners, but were calmer when the partner, an unfamiliar peer, or their own mirror image was visible. MIS elicited more facial expressions than the familiar peer, and more affiliative contact than an unfamiliar peer. In contrast, infants reared in a group were not calmed during separations either by an unfamiliar peer or by MIS, and they exhibited some negative reactions to the mirror. Social responsiveness to MIS varies with the social background of the subjects.