Olympic rankings based on objective weighting schemes

In this paper, we propose an objective principal components weighting scheme for all-time Winter Olympic gold, silver and bronze medals based solely on the number of medals won. Our results suggest that the approximately equal weights be assigned (or the total medal counts be used regardless of color) if all of the three medal types are retained for ranking purposes. When the proposed methodology is tested against five alternative weighting schemes that have been suggested in the literature using the results for the 2010 Vancouver Winter Olympics, we find a significant agreement in the country rankings. Furthermore, our implementation of principal components variable reduction strategy results in the identification of silver as the best representative medal count for parsimonious Winter Olympics rankings.KEYWORDS: Olympic rankings, principal components analysis, variable reduction strategy, medal counts, objective weighting schemeJEL Classifications: C18, C38, C43     

Stationarity test of electromyographic signals during isokinetic trunk exertions

The aim of this study is to investigate the stationarity of the electromyographic (EMG) signals during isokinetic exertions of the trunk muscle. Six healthy subjects participated in this study. The erector spinae muscles were used to collect the signals. In order to simulate the isokinetic exercises of the trunk, a Cybex system with a trunk modular component was used. All subjects performed sustained exertions with a combination of load (25%, 50% MVC) and angular velocity (0, 15, 30 degree/s). The stationarity of the signals was tested by the reverse arrangements test and modified reverse arrangements test. In the results, the signal stationarity was high in all conditions in the reverse arrangements test. However, in the modified reverse arrangements test it was relatively low at about the 30 degree/s angular velocity. In the analysis of variance, the effect of angular velocity was statistically significant at the 0.05 significance level in the modified reverse arrangements test and Tukey's HSD grouping showed that the stationarity of 30 degree/s angular velocity was significantly different from 0, 15 degree/s condition. These results indicate that the stationarity of the EMG signals showed no difference between isometric and isokinetic conditions when the angular velocity was equal to 15 degree/s.     

A reference activity model for smart factory design and improvement

Smart manufacturing systems (SMSs) are envisioned to contain highly automated and IT-driven production systems. To address the complexity that arises in such systems, a standard and holistic model for describing its activities and their interrelationships is needed. This paper introduces a factory design and improvement (FDI) activity model and illustrates a case study of FDI in an electromechanical component factory. In essence, FDI is a reference activity model that encompasses a range of manufacturing system activities for designing and improving a factory during its initial development and also its operational phases. The FDI model shows not only the dependency between activities and manufacturing control levels but also the pieces of information and software functions each activity relies on. We envision that the availability of these pieces of information in digital form to integrate across the software functions will increase the agility of factory design and improvement projects. Therefore, our future work lies in contributing to standards for exchanging such information.     

Child Benefit Portfolios Across OECD Countries

Current research on the cross-national pattern of investment in child benefits mostly adopts the total resources approach and the model family method. The total resources approach conducts a broad comparison of the aggregate expenditure of different types of child benefit across countries. The model family method adds sophistication by comparing the values of child benefit packages of different countries, which combines different levels of spending in each type of child benefit, based on different family types with certain assumed characteristics. To complement the existing approaches, this study uses cluster analysis to classify countries into groups of similar investment strategies by simultaneously counting the different types and levels of child benefits of all countries. The findings show that four types of child benefit investment portfolio, namely Active, Moderate, Conservative, and Minimal, can be identified across OECD countries. While some studies have focused on the effects of individual types of child benefit on child outcomes, little is known about the effects of child benefits as a whole. The pattern of child benefits as investment portfolios could serve as a basis facilitating further investigation into its relationship with child outcomes. Preliminary findings indicate that child poverty, health, and satisfaction with school life differ significantly across investment portfolios, especially Active Investment outperforms Minimal Investment consistently.     

Tweeting India’s Nirbhaya protest: a study of emotional dynamics in an online social movement

Abstract

Previous research has recognized the role of emotions in protests and social movements in the offline world. Despite the current scenario of ubiquitous social media and ‘Twitter revolutions,’ our knowledge about the connections between emotions and online protests still remains limited. In this study, we examine whether online protest actions follow the same emotional groundwork for supporting and nurturing a social movement as in the offline world, and how these emotions vary across various stages of the social movement. Through a computer-assisted emotion analysis of 65,613 Twitter posts (tweets), posted during the Nirbhaya social movement (movement against the Delhi gang-rape incident) in India, we identified a strong resemblance between online emotional patterns and offline protest emotions as discussed in literature. Formal statistical testing of a range of emotions (negativity, positivity, anger, sadness, anxiety, certainty, individualism, collectivism, and achievement) demonstrates that they significantly differed across stages of the social movement; as such, they influenced the course of the online protest, resonating parallels with offline events. The findings highlight the importance of anger and anxiety in stirring the collective conscience, and identify that positive emotion was pervasive during the protest event. Implications of these findings are discussed.     

Difference-based matrix perturbation method for semi-parametric regression with multicollinearity

This paper addresses the collinearity problems in semi-parametric linear models. Under the difference-based settings, we introduce a new diagnostic, the difference-based variance inflation factor (DVIF), for detecting the presence of multicollinearity in semi-parametric models. The DVIF is then used to device a difference-based matrix perturbation method for solving the problem. The electricities distribution data set is analyzed, and numerical evidences validate the effectiveness of the proposed method.     

VIF-based adaptive matrix perturbation method for heteroskedasticity-robust covariance estimators in the presence of multicollinearity

In this study, we investigate linear regression having both heteroskedasticity and collinearity problems. We discuss the properties related to the perturbation method. Important observations are summarized as theorems. We then prove the main result that states the heteroskedasticity-robust variances can be improved and that the resulting bias is minimized by using the matrix perturbation method. We analyze a practical example for validation of the method.     

The longitudinal effects of influence of parental attachment and emotion regulation on Internet delinquency in early adolescence

ABSTRACT

The purpose of this study was to identify the longitudinal influence of parental attachment and emotion regulation on changes in Internet delinquency. This study used the Korean Youth Panel Survey (KYPS) data, in which 2,844 school-age children were annually assessed from Grade 4 in 2004 to Grade 8 in 2008 in South Korea. Latent growth models were used to examine developmental trajectories of Internet delinquency, parental attachment, and emotion regulation longitudinally. This study showed that adolescents experience an increase in Internet delinquency over the fourth year and a decline in the fifth year. The initial level of parental monitoring had significant effects on the initial level of emotion regulation. In addition, the initial level of parental attachment was associated with a slower rate of acceleration of Internet delinquency across time. The study findings indicate that parental attachment influences Internet delinquency among Korean adolescents. The practice implications of the findings are discussed in terms of Internet delinquency reduction efforts.     

A Social Network Contagion Theory of Risk Perception

Risk perceptions have, to a great extent, been studied exclusively as individual cognitive mechanisms in which individuals collect, process, and form perceptions as atomized units unconnected to a social system. These individual-level theories do not, however, help explain how perception of risk may vary between communities or within a single community. One alternative approach is based on a network theory of contagion. This approach, emerging largely from organizational and community social network studies, suggests that it is the relational aspects of individuals and the resulting networks and self-organizing systems that influence individual perceptions and build "groups or communities of like-minded" individuals. These social units, it is argued, behave as attitude, knowledge, or behavioral structures. The study reported in this article tests one aspect of this theoretical perspective. The central hypothesis proposes the existence of risk perception networks--relational groupings of individuals who share, and perhaps create, similar risk perceptions. To test this idea, data were collected from individuals involved in a community environmental conflict over a hazardous waste site cleanup. The statistical analysis used a matrix of relational social linkages to compare with a matrix of individual risk perceptions The analysis confirmed the hypothesis suggesting that social linkages in communities may play an important role in focusing risk perceptions.     

Basic Psychological Need Profiles and Correlates in Volunteers for a National Sports Event

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - According to the basic psychological need theory, satisfaction and frustration of basic psychological needs are related to...