Assessing reproducibility of data obtained with instruments based on continuous measurements

Data obtained with any research tool must be reproducible, a concept referred to as reliability. Three techniques are often used to evaluate reliability of tools using continuous data in aging research: intraclass correlation coefficients (ICC), Pearson correlations, and paired t tests. These are often construed as equivalent when applied to reliability. This is not correct, and may lead researchers to select instruments based on statistics that may not reflect actual reliability. The purpose of this paper is to compare the reliability estimates produced by these three techniques and determine the preferable technique. A hypothetical dataset was produced to evaluate the reliability estimates obtained with ICC, Pearson correlations, and paired t tests in three different situations. For each situation two sets of 20 observations were created to simulate an intrarater or inter-rater paradigm, based on 20 participants with two observations per participant. Situations were designed to demonstrate good agreement, systematic bias, or substantial random measurement error. In the situation demonstrating good agreement, all three techniques supported the conclusion that the data were reliable. In the situation demonstrating systematic bias, the ICC and t test suggested the data were not reliable, whereas the Pearson correlation suggested high reliability despite the systematic discrepancy. In the situation representing substantial random measurement error where low reliability was expected, the ICC and Pearson coefficient accurately illustrated this. The t test suggested the data were reliable. The ICC is the preferred technique to measure reliability. Although there are some limitations associated with the use of this technique, they can be overcome.

An Enactive Approach to the Design of New Tangible Musical Instruments

In this paper, we propose a theoretical framework for the design of tangible interfaces for musical expression. The main insight for the proposed approach is the importance and utility of familiar sensorimotor experiences for the creation of engaging and playable new musical instruments. In particular, we suggest exploiting the commonalities between different natural interactions by varying the auditory response or tactile details of the instrument within certain limits. Using this principle, devices for classes of sounds such as coarse grain collision interactions or friction interactions can be designed. The designs we propose retain the familiar tactile aspect of the interaction so that the performer can take advantage of tacit knowledge gained through experiences with such phenomena in the real world.

A SuperWASP search for additional transiting planets in 24 known systems

We present results from a search for additional transiting planets in 24 systems already known to contain a transiting planet. We model the transits due to the known planet in each system and subtract these models from light curves obtained with the SuperWASP (Wide Angle Search for Planets) survey instruments. These residual light curves are then searched for evidence of additional periodic transit events. Although we do not find any evidence for additional planets in any of the planetary systems studied, we are able to characterize our ability to find such planets by means of Monte Carlo simulations. Artificially generated transit signals corresponding to planets with a range of sizes and orbital periods were injected into the SuperWASP photometry and the resulting light curves searched for planets. As a result, the detection efficiency as a function of both the radius and orbital period of any second planet is calculated. We determine that there is a good (>50 per cent) chance of detecting additional, Saturn-sized planets in P ~ 10 d orbits around planet-hosting stars that have several seasons of SuperWASP photometry. Additionally, we confirm previous evidence of the rotational stellar variability of WASP-10, and refine the period of rotation. We find that the period of the rotation is 11.91 +/- 0.05 d, and the false alarm probability for this period is extremely low (~10-13).

A experiência barroca e a identidade local na Semana Santa de Campanha, Minas Gerais

Este trabalho analisa a formação de uma sensibilidade barroca em Minas Gerais a partir da orientação participativa e altamente emotiva das festas coloniais, cujo legado se mantem presente nas festas religiosas de muitas antigas cidades mineradoras do estado. Enfocando as celebrações da Semana Santa na cidade sul-mineira de Campanha, o texto mostra como este evento anual era organizado pela Irmandade do Santíssimo Sacramento, passando então às mãos de uma comissão local após a extinção da irmandade. Se até meados do século XIX, havia músicos semi-profissionais contratados para tocar e cantar nas celebrações, a música foi assumida progressivamente por grupos de amadores. Assim, a festa passou a ser entendida como uma produção local e a cada ano a população renova o seu orgulho campanhense, ao contemplar sua capacidade de produzir um evento tão ‘maravilhoso’.

This paper analyses the formation of a baroque sensibility in the State of Minas Gerais (Brazil) that derives from the participatory and highly emotive orientation of the colonial festivals, the legacy of which is still present in many former mining towns in the region. By focusing upon the Holy Week celebrations in Campanha, a small town in southern Minas Gerais, the text shows how this annual event was organized by the Confraternity of the Holy Sacrament, but was then transferred to a local committee after the confraternity was made extinct. If up to the mid 19th century there were semi-professional musicians to perform for the celebrations, responsibility for the music was slowly taken over by amateur groups. In this way the festival came to be understood as a local affair, and each year the population renews its pride in itself for its capacity to stage such a ‘marvelous’ event.