Multiple linear regression: Identify potential health care stocks for investments using out-of-sample predictions

College-level statistics courses emphasize the use of the coefficient of determination, R-squared, in evaluating a linear regression model: higher R-squared is better. This often gives students an impression that higher R-squared implies better predictability since textbooks tend to use sample data to support the theory and students rarely have an opportunity to work on real data. In this paper, health care stocks are used as predictors and the result demonstrates that high R-squared does not necessarily mean high predictability and that multiple linear regression can be used in the study of data behavior. In particular, by learning the pattern of the near and far out-of-sample-prediction errors for different time periods throughout a dataset, the near out-of-sample prediction errors can be used to control the prediction errors and identify a subset of predictors that can well reflect the trend of S&P 500.     

Cast Aside

This paper examines the role of user-generated content in a traditional news organization during the coverage of the Boston marathon bombings. In-depth interviews were conducted with the journalists who made up the interactive team at the Boston Globe. The interactive team was in charge of the live blog during the week-long coverage of the marathon bombings. The study identifies the perceptions journalists hold of user-generated content during crisis reporting and the impact user-generated content had during the tense coverage. The findings suggest that user-generated content has a good way to go before being considered an integral part of breaking news content.     

Searching for an image conveying connotative meanings: An exploratory cross-cultural study

On the basis of the semiotics premise, this exploratory study examined cultural influences that pertain to the image search process when users have connotative needs. The study used the Semantic Differential, a quantitative tool for measuring affective reactions, as well as word-based analysis, to analyze responses to a survey questionnaire administered to twelve Korean and twelve American students. The results demonstrated that even when completing the same task, participants from different backgrounds have different tendencies in expecting and selecting a relevant image. The results supported the semiotics assertion that cultural context results in variations in interpreting the connotative messages of an image, and these variations are restricted by cultural boundaries. The study underlined the potential of using the Semantic Differential to enhance accessibility to connotative messages during the image retrieval process. Based on the findings, some suggestions for image retrieval system design were discussed. This study will broaden understanding of connotative messages in terms of image retrieval and user behaviors. The conclusions will contribute to designing a practical image retrieval system that can provide subject access to connotative messages.     

A sociocultural theoretical approach to understanding mentor–mentee interactions during a Teaching English as a Second Language practicum at the master’s degree level

Drawing on the sociocultural theoretical (SCT) perspective, we offer a microgenetic analysis of mentor–mentee interactions in the context of pre-service teachers’ practicum in a Master’s program for Teaching English as a Second Language (TESL). Following two pairs of mentors and mentees, we analyze audio-recorded interactions and interviews and examine in depth how mediation occurs during mentoring and how such mediation assists the mentees in learning to become teachers. Our findings show that mentors’ mediation is dynamic and contingent upon the context in which mentoring occurs and that the quality and character of mentor–mentee interactions during goal-directed activities is a critical feature of promoting the mentees’ learning. Responsive mediation especially plays a key role in promoting the mentees’ cognitive development, and it is an essential component of effective mentoring. This calls for a more SCT-informed approach to conceptualizing mentoring and training mentors in practicums.     

Teachers: A Critical But Overlooked Component of Bullying Prevention and Intervention

To complete this special issue on theoretical bases for antibullying efforts in schools, we focus in this article on the importance of teachers and other educators in the ecology of schools. First, we present evidence that teachers are not perceived to be effective at intervening when bullying occurs. Then, using a social motivational lens, we provide an overview of teachers' role as a socializing agent in the classroom and school with a particular emphasis on their influence on bullying behaviors among students. Then we present two theories, the theory of planned behaviors, and the transactional theory of emotions and coping. We believe these theories highlight the complexity of teacher responses and make the case that teachers need more than knowledge of bullying to be effective in their role. We discuss implications for teacher training and professional development.     

Patterns of coparenting and young children's social–emotional adjustment in low-income families

This study identified coparenting patterns using data collected across 2007–2010 from low-income couples (N = 2915; 26.90% non-Hispanic White; 9.41% non-Hispanic Black; 34.24% Hispanic, 29.27% other or mixed race) with young children (M = 3.65 years; SD = 1.31 years; 48% girls) and examined relations with children's social–emotional adjustment. Latent profile analysis revealed four coparenting patterns: mutual high-quality (43.4%), moderate-quality, mothers less positive (31.8%), moderate-quality, fathers less positive (15.9%), and low-quality, mothers less positive (8.9%). When parents' perspectives on coparenting were positive and congruent, children fared best. Children also fared well when coparenting quality was moderate, and mothers were less positive than fathers. When coparenting quality was moderate and fathers were less positive than mothers, children showed the poorest adjustment.     

The effect of self‐directed work teams on work ethic

This study examined the work ethic of manufacturing machine operators between self‐directed work teams and traditional work groups using four work ethic subscales: dependable, considerate, ambitious, and cooperative (Dawson, 1999 ; Petty, 1991 ). Differences in measured work ethic scores were also compared across six demographic variables: age, gender, level of education, years of full‐time work experience, years of experience as a supervisor, and work shift preference. Findings showed that there were significant differences in the work ethic between those two team structures and age groups. Implications for future research were presented.     

Searching images in daily life

With the proliferation of images in daily life, it is crucial to investigate what, where, why and how people search images in response to their everyday needs. In order to examine the daily needs of image searchers, a survey questionnaire was administered to 58 college students. The results demonstrated that the majority of college students use Google or Google Image for searching images, because of its familiarity and user-friendly interface. Although searchers reported a high success rate (85.6%) of image retrieval, they wanted search engines to return more relevant images and fewer irrelevant and redundant images. They also desired search engines to provide high resolution and full scale images. Students searched for images for various purposes, including to: prepare presentation materials, use as computer wallpaper, get ideas for purchasing, travel destinations, or beauty/fashion items, see what something looks like, verify names, solve problems, out of curiosity, and so on. Some types of needs revealed that users were interested in associated textual information, as well as the image itself. The implications for image retrieval system design are 1) it is proposed that metadata information (size, quality, type, copyright information) be utilized in browsing or navigating images, and 2) further research on an information retrieval system that can support users looking for both text and images concurrently is suggested.