Narratives of the 'everyday' in Rio de Janeiro's favelas : community photographers' attempts at generating alternative news values [Narrativas do cotidiano nas favelas do Rio de Janeiro: tentativas de construção de valores-notícia alternativos pelos fotógrafos populares]

Abstract This paper presents the partial results of an ongoing research project which investigates ethnographically community (photo)journalism media initiatives, in Rio de Janeiro, Brazil. The Viva Rio and Observatorio de Favelas (NGOs) run projects that provide favela residents with skills to take, edit and print their own (photo) journalism contents that enables community-based framing and documentation of favela live, personalities and issues. Three months of fieldwork related to these projects in Rio's favelas generated remarkable theoretical issues that represent the community photographers' attempt to establish counter news values by shifting the focus from poverty, shortages, violence and criminality to images of the ordinary life which included the myriad events that occurs in the day of the favelas. Resumo Este artigo apresenta os resultados parciais de uma pesquisa em andamento que, a partir do método etnográfico, investiga os projetos de comunicação comunitária, jornalismo e fotojornalismo, no Rio de Janeiro, Brasil. As organizações não-governamentais (ONGs) Viva Rio e Observatório de Favela apoiam projetos que objetivam tornar moradores de favelas capazes de produzir, editar e publicar as suas próprias narrativas sobre personagens e questões do cotidiano de suas comunidades. O trabalho de campo sobre estes projetos, realizado durante três meses nas favelas do Rio de Janeiro, forneceu questões teóricas relevantes que representam o esforço dos fotógrafos populares para estabelecer contra valores-notícia transferindo o foco da pobreza, escassez, violência e criminalidade para imagens do cotidiano que inclui uma miríade de eventos que acontecem no dia-a-dia das favelas.

Narratives of the 'everyday' in Rio de Janeiro's favelas : the construction of alternative news values by community photographers [Narrativas do cotidiano nas favelas cariocas: a problematizacao dos valores-noticia pelos fotografos populares]

Resumo: Esse artigo apresenta os resultados parciais de uma pesquisa em andamento que, a partir do método etnográfico, investiga os projetos de comunicação comunitária, jornalismo e fotojornalismo desenvolvidos por duas organizações não-governamentais na cidade do Rio de Janeiro. O trabalho de campo, realizado durante três meses nas favelas cariocas, forneceu questões teóricas relevantes para os estudos do jornalismo, destacando-se as problematizações sobre a noção de valores-notícia. Voltados para a produção de narrativas centradas no cotidiano das comunidades, os fotojornalistas populares consideram fundamental discutir os valores-notícia formulados pela grande imprensa e propor “contra-valores”.

Approximation of Bayesian predictive p-values with regression ABC

In the Bayesian framework a standard approach to model criticism is to compare some function of the observed data to a reference predictive distribution. The result of the comparison can be summarized in the form of a p-value, and it's well known that computation of some kinds of Bayesian predictive p-values can be challenging. The use of regression adjustment approximate Bayesian computation (ABC) methods is explored for this task. Two problems are considered. The first is the calibration of posterior predictive p-values so that they are uniformly distributed under some reference distribution for the data. Computation is difficult because the calibration process requires repeated approximation of the posterior for different data sets under the reference distribution. The second problem considered is approximation of distributions of prior predictive p-values for the purpose of choosing weakly informative priors in the case where the model checking statistic is expensive to compute. Here the computation is difficult because of the need to repeatedly sample from a prior predictive distribution for different values of a prior hyperparameter. In both these problems we argue that high accuracy in the computations is not required, which makes fast approximations such as regression adjustment ABC very useful. We illustrate our methods with several samples.

Consistency errors in p-values reported in Spanish psychology journals

Resumen tomado de la publicación

Incongruence between test statistics and P values in medical papers

Given an observed test statistic and its degrees of freedom, one may compute the observed P value with most statistical packages. It is unknown to what extent test statistics and P values are congruent in published medical papers. Methods: We checked the congruence of statistical results reported in all the papers of volumes 409–412 of Nature (2001) and a random sample of 63 results from volumes 322–323 of BMJ (2001). We also tested whether the frequencies of the last digit of a sample of 610 test statistics deviated from a uniform distribution (i.e., equally probable digits).Results: 11.6% (21 of 181) and 11.1% (7 of 63) of the statistical results published in Nature and BMJ respectively during 2001 were incongruent, probably mostly due to rounding, transcription, or type-setting errors. At least one such error appeared in 38% and 25% of the papers of Nature and BMJ, respectively. In 12% of the cases, the significance level might change one or more orders of magnitude. The frequencies of the last digit of statistics deviated from the uniform distribution and suggested digit preference in rounding and reporting.Conclusions: this incongruence of test statistics and P values is another example that statistical practice is generally poor, even in the most renowned scientific journals, and that quality of papers should be more controlled and valued

Appropriateness of reporting statistical results in orthodontics: the dominance of P values over confidence intervals

The purpose of this study was to search the orthodontic literature and determine the frequency of reporting of confidence intervals (CIs) in orthodontic journals with an impact factor. The six latest issues of the American Journal of Orthodontics and Dentofacial Orthopedics, the European Journal of Orthodontics, and the Angle Orthodontist were hand searched and the reporting of CIs, P values, and implementation of univariate or multivariate statistical analyses were recorded. Additionally, studies were classified according to the type/design as cross-sectional, case-control, cohort, and clinical trials, and according to the subject of the study as growth/genetics, behaviour/psychology, diagnosis/treatment, and biomaterials/biomechanics. The data were analyzed using descriptive statistics followed by univariate examination of statistical associations, logistic regression, and multivariate modelling. CI reporting was very limited and was recorded in only 6 per cent of the included published studies. CI reporting was independent of journal, study area, and design. Studies that used multivariate statistical analyses had a higher probability of reporting CIs compared with those using univariate statistical analyses. Misunderstanding of the use of P values and CIs may have important implications in implementation of research findings in clinical practice.

Reporting of statistical results in prosthodontic and implantology journals: p values or confidence intervals?

PURPOSE Confidence intervals (CIs) are integral to the interpretation of the precision and clinical relevance of research findings. The aim of this study was to ascertain the frequency of reporting of CIs in leading prosthodontic and dental implantology journals and to explore possible factors associated with improved reporting. MATERIALS AND METHODS Thirty issues of nine journals in prosthodontics and implant dentistry were accessed, covering the years 2005 to 2012: The Journal of Prosthetic Dentistry, Journal of Oral Rehabilitation, The International Journal of Prosthodontics, The International Journal of Periodontics & Restorative Dentistry, Clinical Oral Implants Research, Clinical Implant Dentistry and Related Research, The International Journal of Oral & Maxillofacial Implants, Implant Dentistry, and Journal of Dentistry. Articles were screened and the reporting of CIs and P values recorded. Other information including study design, region of authorship, involvement of methodologists, and ethical approval was also obtained. Univariable and multivariable logistic regression was used to identify characteristics associated with reporting of CIs. RESULTS Interrater agreement for the data extraction performed was excellent (kappa = 0.88; 95% CI: 0.87 to 0.89). CI reporting was limited, with mean reporting across journals of 14%. CI reporting was associated with journal type, study design, and involvement of a methodologist or statistician. CONCLUSIONS Reporting of CI in implant dentistry and prosthodontic journals requires improvement. Improved reporting will aid appraisal of the clinical relevance of research findings by providing a range of values within which the effect size lies, thus giving the end user the opportunity to interpret the results in relation to clinical practice.

On the hydrophobicity of peptides:comparing empirical predictions of peptide log P values

Peptides are of great therapeutic potential as vaccines and drugs. Knowledge of physicochemical descriptors, including the partition coefficient logP, is useful for the development of predictive Quantitative Structure-Activity Relationships (QSARs). We have investigated the accuracy of available programs for the prediction of logP values for peptides with known experimental values obtained from the literature. Eight prediction programs were tested, of which seven programs were fragment-based methods: XLogP, LogKow, PLogP, ACDLogP, AlogP, Interactive Analysis's LogP and MlogP; and one program used a whole molecule approach: QikProp. The predictive accuracy of the programs was assessed using r(2) values, with ALogP being the most effective (r( 2) = 0.822) and MLogP the least (r(2) = 0.090). We also examined three distinct types of peptide structure: blocked, unblocked, and cyclic. For each study (all peptides, blocked, unblocked and cyclic peptides) the performance of programs rated from best to worse is as follows: all peptides - ALogP, QikProp, PLogP, XLogP, IALogP, LogKow, ACDLogP, and MlogP; blocked peptides - PLogP, XLogP, ACDLogP, IALogP, LogKow, QikProp, ALogP, and MLogP; unblocked peptides - QikProp, IALogP, ALogP, ACDLogP, MLogP, XLogP, LogKow and PLogP; cyclic peptides - LogKow, ALogP, XLogP, MLogP, QikProp, ACDLogP, IALogP. In summary, all programs gave better predictions for blocked peptides, while, in general, logP values for cyclic peptides were under-predicted and those of unblocked peptides were over-predicted.

Hypothesis test for changes in variance using a statistic based in P-values in a time series of normal independent observations.

The present work proposes a Hypothesis Test to detect a shift in the variance of a series of independent normal observations using a statistic based on the p-values of the F distribution. Since the probability distribution function of this statistic is intractable, critical values were we estimated numerically through extensive simulation. A regression approach was used to simplify the quantile evaluation and extrapolation. The power of the test was simulated using Monte Carlo simulation, and the results were compared with the Chen test (1997) to prove its efficiency. Time series analysts might find the test useful to address homoscedasticity studies were at most one change might be involved.

The use of complementary and alternative medicine among people living with diabetes in Sydney

Background: Complementary and alternative medicine (CAM) is common in patients with chronic disease such as diabetes mellitus. The primary objective of the study was to determine the overall prevalence and type of CAM use in individuals with diabetes mellitus (DM) in Western Sydney and to compare the prevalence and factors associated with CAM use with the literature.

Methods: A multicenter cross-sectional study was undertaken using a self-completed questionnaire distributed to patients with DM attending a public hospital and specialist endocrinology clinics in the region. The type of DM and pattern of CAM utilisation were analyzed.

Results: Sixty nine people responded to the questionnaire: age range of 18-75 years during a twelve week collection period. Overall, 32 respondents with diabetes were using some form of CAM, resulting in a utilisation rate of 46.3%. Twenty of the 32 CAM users used CAM specifically to treat their diabetes accounting for 28.9% of the respondent sample population. Multivitamins (40%), cinnamon, Co-enzyme q10 and prayer were the most frequently used CAM modalities. There was no significant difference between males and females, age range, income or diabetes complications between CAM and non-CAM users. (p values each > 0.05) The factor most significantly associated with CAM usage was being born overseas (p = 0.044).

Conclusions: Almost half the respondents (46.3%) used CAM: 28% used CAM specifically to treat their diabetes. Individuals born overseas were significantly more likely to use CAM than those born in Australia. Other factors such as age, gender, wealth and duration of living with diabetes were not associated with higher rate of CAM usage.