Multiple visualisation in data analysis: a ViSta application for principal component analysis

Multiple visualisation (MV) is a statistic graphical method barely applied in data analysis practice, even though it provides interesting features for this purpose. This paper: (1) describes the application of the MV graphical method; (2) presents a number of rules related to the design of an MV; (3) introduces a general outline for developing MVs and shows how MV may be implemented in the ViSta statistical system; (4) illustrates this strategy by means of an example of MV oriented to principal component analysis; and, finally, (5) discusses some limitations of using and developing MVs.     

Illusion of control in Internet users and college students.

When people try to obtain a desired event and this outcome occurs independently of their behavior, they often think that they are controlling its occurrence. This is known as the illusion of control, and it is the basis for most superstitions and pseudosciences. However, most experiments demonstrating this effect had been conducted many years ago and almost always in the controlled environment of the psychology laboratory and with psychology students as subjects. Here, we explore the generality of this effect and show that it is still today a robust phenomenon that can be observed even in the context of a very simple computer program that users try to control (and believe that they are controlling) over the Internet. Understanding how robust and general this effect is, is a first step towards eradicating irrational and pseudoscientific thinking.     

Attentional bias for doping words and its relation with physical self-esteem in young adolescents

ObjectivesPrevious studies revealed that adolescence is a period of risk for doping and drug addiction and that young athletes who used doping agents reported low self-esteem. We conducted a preventive study with the aims to investigate whether young adolescents displayed an attentional bias to doping-related words and whether this attentional bias was related to physical self-esteem.MethodNinety seven adolescents (44 girls and 53 boys) from 11 to 15 years-old participated to a study designed to measure reaction times (RT) in a Stroop emotional task related to doping, cheating and control words. They also completed the Physical Self-Perception Profile subscales assessing perceived general self-esteem, physical self-worth, physical condition, sport competence, body attractiveness, and physical strength.ResultsParticipants exhibited longer RT after doping words than after control words. RT was also longer after doping than after cheating words. Participants belonging to the low physical self-esteem group exhibited larger carry-over effects than those who were in the high physical self-esteem group.ConclusionsThese findings suggest that attentional resources allocated to doping words are already present at the onset of adolescence, and that they may be linked to a psychological feature (physical self-esteem) considered as a risk factor of substance abuse in young adults involved in competitive sports.     

Classical item and test analysis with graphics: The ViSta-CITA program

Current advances in test development theory have mostly been influenced by item response theory. Notwithstanding this, classical test theory still plays a major part in the development of tests for applied educational and behavioral research. This article describes ViSta-CITA, a computer program that implements a set of classical item and test analysis methods that incorporate innovative graphics whose aim is to provide deeper insight into analysis results. Such an aim is achieved through the SpreadPlot, a graphical method designed to display multiple, simultaneous, interactive views of the analysis results. It behaves on a dynamic basis, so that users’ changes (e.g., selecting a subset of items) are automatically updated in the graphical windows showing the analysis results. Moreover, ViSta-CITA is freely available, and its code is open to modifications or additions by the user. Features such as these constitute useful tools for research and teaching purposes related to test development.     

Commuting Conversions vs. the Standard Conversions of the “Good” Connectives

Commuting conversions were introduced in the natural deduction calculus as ad hoc devices for the purpose of guaranteeing the subformula property in normal proofs. In a well known book, Jean-Yves Girard commented harshly on these conversions, saying that ‘one tends to think that natural deduction should be modified to correct such atrocities.’ We present an embedding of the intuitionistic predicate calculus into a second-order predicative system for which there is no need for commuting conversions. Furthermore, we show that the redex and the conversum of a commuting conversion of the original calculus translate into equivalent derivations by means of a series of bidirectional applications of standard conversions. Presented by Heinrich Wansing and Jacek Malinowski     

Charitable giving among the foreign-born in Canada

This article focuses on the patterns of charitable giving among the foreign-born in Canada. Using Joseph's (1995) “spectrum of philanthropy” model, we generated four general empirical predictions that were explored with Canadian data. The sample used for the analysis were 18,301 Canadian and foreign-born respondents drawn from the National Survey of Giving, Volunteering and Participating. All four predictions were supported by the survey data. Substantial variations in the propensities to give were found among immigrant groups in terms of their birthplaces, socio-demographic, and residential characteristics. Some segments of the immigrant population displayed higher propensities to give than those who were Canadian-born. As the length of residence increased, the average contributions of the foreign-born increased but with some changes in their underlying motivations and organizational preferences. Religion-related motivations declined some-what over time. Although religious organizations were always preferred throughout the immigrant integration process, it was found that more secular organizations (i.e., health-and social services-related) received more support at the latter stages of this process.     

Habituation of exploratory activity to new stimuli, to the absence of a previously presented stimulus and to new contexts, in rats

Rats trained to run a shuttle-alleyway for food exhibited exploratory behaviour to a novel visual/tactual stimulus presented in a specific place of the alley. Intermittent presentation of the same stimulus in the same place resulted in reduction of the exploratory activity (habituation), both within and between sessions. The animals also directed exploratory activity to the absence of the previously presented stimulus at the place where the stimulus had been presented before; this latter response also habituated. The presentation (1) of the same stimulus to which the animals had already habituated in another place in the alleyway or when the animals were running in an opposite direction to the previous trials of stimulus presentation, or (2) of another stimulus, resulted, again, in the appearance of exploratory activity. These results lead to the conclusion that the animals code external events, store this information, and use it to detect spatial- and directional-contextual changes and to generate predictions about that specific environment.