Disgust as the Source of False Positive Effects in the Measurement of Ophidiophobia

1997 ◽  
Vol 131 (4) ◽  
pp. 371-382 ◽  
Author(s):  
Douglas M. Klieger ◽  
Kimberly K. Siejak
2017 ◽  
Author(s):  
G. Lohmann ◽  
J. Stelzer ◽  
K. Müller ◽  
E. Lacosse ◽  
T. Buschmann ◽  
...  

AbstractReproducibility is generally regarded as a hallmark of scientific validity. It can be undermined by two very different factors, namely inflated false positive rates or inflated false negative rates. Here we investigate the role of the second factor, i.e. the degree to which true effects are not detected reliably. The availability of large public databases and also supercomputing allows us to tackle this problem quantitatively. Specifically, we estimated the reproducibility in task-based fMRI data over different samples randomly drawn from a large cohort of subjects obtained from the Human Connectome Project. We use the full cohort as a standard of reference to approximate true positive effects, and compute the fraction of those effects that was detected reliably using standard software packages at various smaller sample sizes. We found that with standard sample sizes this fraction was less than 25 percent. We conclude that inflated false negative rates are a major factor that undermine reproducibility. We introduce a new statistical inference algorithm based on a novel test statistic and show that it improves reproducibility without inflating false positive rates.


2020 ◽  
Author(s):  
Jan Walleczek ◽  
Von Stillfried

A general commentary by Walleczek and von Stillfried (2020) was recently published in Frontiers in Psychology. The present work provides an account of (i) the detailed research record and (ii) the main arguments behind the commentary for the purpose of full transparency and disclosure. For historical overview, Walleczek and von Stillfried (2019) had previously reported (i) the absence of any true-positive effects and (ii) the presence of one false-positive effect in a commissioned replication study of the Radin double-slit (DS) experiment on observer consciousness. In their subsequent misrepresentations, Radin et al. (2019, 2020) regrettably used the malpractice of undisclosed HARKing, i.e., undisclosed hypothesizing after the results are known. HARKing can increase greatly the risk of false-negative or false-positive conclusions. Specifically, Radin et al. (2019, 2020) deviated in two major ways from the pre-specified protocol for this commissioned study, which (i) was agreed to by Radin before data collection was started (Radin, 2011) and (ii) included data encryption to prevent the use of p-hacking and HARKing. First, Radin et al. (2019) violate the original research design by reporting a so-called “true-positive outcome of a secondary planned hypothesis”. Contrary to the claim by Radin et al. (2019, 2020), that hypothesis was not, however, part of the planned test strategy, but, instead, the associated statistical analysis – a chi-square test – was chosen by Radin sometime after the planned statistical analysis had been completed and the data unblinded. Second, Radin et al. (2019, 2020) violate the funder-approved research design in an additional way by falsely claiming that the newly developed protocol, i.e., the advanced meta-experimental protocol (AMP), implements a non-predictive test strategy when – in fact – the AMP-based test strategy is strictly predictive. Put simply, Radin et al. (2019, 2020) are mistaken that the funder-approved hypotheses posited the random occurrence of effects for the test categories in this replication experiment; instead, a different specific prediction was tested in each of the eight planned test categories, and true-positive effects were predicted to occur for only two (12.5%) of the 16 possible measurement outcomes of the eight planned single-test categories. Therefore, in the predictive single-testing regime, a statistical correction for non-predictive, i.e., random, multiple testing would not be appropriate and would thus violate the AMP-based strategy, which was implemented in the commissioned study based upon the planned outcome predictions as pre-specified in Radin (2011). Neither of these post-hoc changes by Radin et al. (on the basis of HARKing) were disclosed in Radin et al. (2019, 2020) and both these changes violate the funder-approved, original methodology agreed upon in Radin (2011) and pre-specified in the research contract. In summary, the present work reconfirms that – exactly as reported in Walleczek and von Stillfried (2019) – “the false-positive effect, which would be indistinguishable from the predicted true-positive effect, was significant at p = 0.021 (σ = −2.02; N = 1,250 test trials)” and “no statistically significant effects could be identified” in those two groups for which true-positives were predicted to occur. These observations are consistent also with an independent statistical reanalysis of the Radin DS-experiment by Tremblay (2019) and a replication attempt by Guerrer (2019). Tremblay reported significant false-positives in control groups and Guerrer found significant effects with post-hoc analyses only, but null results only when using the planned confirmatory analysis. As a general recommendation, the authors call for the implementation of advanced control-test strategies, including novel approaches from the metascience reform movement, for empirically detecting and preventing uncontrolled false-positive effects in parapsychological research.


2012 ◽  
Vol 7 (6) ◽  
pp. 531-536 ◽  
Author(s):  
Harold Pashler ◽  
Christine R. Harris

We discuss three arguments voiced by scientists who view the current outpouring of concern about replicability as overblown. The first idea is that the adoption of a low alpha level (e.g., 5%) puts reasonable bounds on the rate at which errors can enter the published literature, making false-positive effects rare enough to be considered a minor issue. This, we point out, rests on statistical misunderstanding: The alpha level imposes no limit on the rate at which errors may arise in the literature (Ioannidis, 2005b). Second, some argue that whereas direct replication attempts are uncommon, conceptual replication attempts are common—providing an even better test of the validity of a phenomenon. We contend that performing conceptual rather than direct replication attempts interacts insidiously with publication bias, opening the door to literatures that appear to confirm the reality of phenomena that in fact do not exist. Finally, we discuss the argument that errors will eventually be pruned out of the literature if the field would just show a bit of patience. We contend that there are no plausible concrete scenarios to back up such forecasts and that what is needed is not patience, but rather systematic reforms in scientific practice.


Author(s):  
M. Tajmar ◽  
O. Neunzig ◽  
M. Weikert

AbstractThe EMDrive is a proposed propellantless propulsion concept claiming to be many orders of magnitude more efficient than classical radiation pressure forces. It is based on microwaves, which are injected into a closed tapered cavity, producing a unidirectional thrust with values of at least 1 mN/kW. This was met with high scepticism going against basic conservation laws and classical mechanics. However, several tests and theories appeared in the literature supporting this concept. Measuring a thruster with a significant thermal and mechanical load as well as high electric currents, such as those required to operate a microwave amplifier, can create numerous artefacts that produce false-positive thrust values. After many iterations, we developed an inverted counterbalanced double pendulum thrust balance, where the thruster can be mounted on a bearing below its suspension point to eliminate most thermal drift effects. In addition, the EMDrive was self-powered by a battery-pack to remove undesired interactions due to feedthroughs. We found no thrust values within a wide frequency band including several resonance frequencies and different modes. Our data limit any anomalous thrust to below the force equivalent from classical radiation for a given amount of power. This provides strong limits to all proposed theories and rules out previous test results by at least two orders of magnitude.


2020 ◽  
Vol 63 (4) ◽  
pp. 1018-1032
Author(s):  
Chia-Hsin Wu ◽  
Roger W. Chan

Purpose Semi-occluded vocal tract (SOVT) exercises with tubes or straws have been widely used for a variety of voice disorders. Yet, the effects of longer periods of SOVT exercises (lasting for weeks) on the aging voice are not well understood. This study investigated the effects of a 6-week straw phonation in water (SPW) exercise program. Method Thirty-seven elderly subjects with self-perceived voice problems were assigned into two groups: (a) SPW exercises with six weekly sessions and home practice (experimental group) and (b) vocal hygiene education (control group). Before and after intervention (2 weeks after the completion of the exercise program), acoustic analysis, auditory–perceptual evaluation, and self-assessment of vocal impairment were conducted. Results Analysis of covariance revealed significant differences between the two groups in smoothed cepstral peak prominence measures, harmonics-to-noise ratio, the auditory–perceptual parameter of breathiness, and Voice Handicap Index-10 scores postintervention. No significant differences between the two groups were found for other measures. Conclusions Our results supported the positive effects of SOVT exercises for the aging voice, with a 6-week SPW exercise program being a clinical option. Future studies should involve long-term follow-up and additional outcome measures to better understand the efficacy of SOVT exercises, particularly SPW exercises, for the aging voice.


2019 ◽  
Vol 4 (6) ◽  
pp. 1589-1594
Author(s):  
Yvonne van Zaalen ◽  
Isabella Reichel

Purpose Among the best strategies to address inadequate speech monitoring skills and other parameters of communication in people with cluttering (PWC) is the relatively new but very promising auditory–visual feedback (AVF) training ( van Zaalen & Reichel, 2015 ). This study examines the effects of AVF training on articulatory accuracy, pause duration, frequency, and type of disfluencies of PWC, as well as on the emotional and cognitive aspects that may be present in clients with this communication disorder ( Reichel, 2010 ; van Zaalen & Reichel, 2015 ). Methods In this study, 12 male adolescents and adults—6 with phonological and 6 with syntactic cluttering—were provided with weekly AVF training for 12 weeks, with a 3-month follow-up. Data was gathered on baseline (T0), Week 6 (T1), Week 12 (T2), and after follow-up (T3). Spontaneous speech was recorded and analyzed by using digital audio-recording and speech analysis software known as Praat ( Boersma & Weenink, 2017 ). Results The results of this study indicated that PWC demonstrated significant improvements in articulatory rate measurements and in pause duration following the AVF training. In addition, the PWC in the study reported positive effects on their ability to retell a story and to speak in more complete sentences. PWC felt better about formulating their ideas and were more satisfied with their interactions with people around them. Conclusions The AVF training was found to be an effective approach for improving monitoring skills of PWC with both quantitative and qualitative benefits in the behavioral, cognitive, emotional, and social domains of communication.


2001 ◽  
Vol 120 (5) ◽  
pp. A314-A315
Author(s):  
D FRANCHIMONT ◽  
J GALON ◽  
M VACCHIO ◽  
R VISCONTI ◽  
G CHROUSOS ◽  
...  

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