Investigation of Regression-Based Effect Size Methods Developed in Single-Subject Studies

The purpose of this study is to provide a brief introduction to effect size calculation in single-subject design studies, including a description of nonparametric and regression-based effect sizes. We then focus the rest of the tutorial on common regression-based methods used to calculate effect size in single-subject experimental studies. We start by first describing the difference between five regression-based methods (Gorsuch, White et al., Center et al., Allison and Gorman, Huitema and McKean). This is followed by an example using the five regression-based effect size methods and a demonstration how these methods can be applied using a sample data set. In this way, the question of how the values obtained from different effect size methods differ was answered. The specific regression models used in these five regression-based methods and how these models can be obtained from the SPSS program were shown. R2 values obtained from these five methods were converted to Cohen’s d value and compared in this study. The d values obtained from the same data set were estimated as 0.003, 0.357, 2.180, 3.470, and 2.108 for the Allison and Gorman, Gorsuch, White et al., Center et al., as well as for Huitema and McKean methods, respectively. A brief description of selected statistical programs available to conduct regression-based methods was given.

Mindfulness Based Therapy in Cancer Patients: Meta-Analysis

Evidence suggested that mindfulness-based techniques have been effective in increasing psychological well-being. The present meta-analytic study aimed to examine the effects of mindfulness-based programmes on anxiety, and depression in cancer infected and survivors. Improvement in mindfulness across groups were also studied. Using various search items (e.g., MBCT, MBSR, Cancer). A systematic search of the electronic databases, reference list, and journal content lists were conducted from June 2011 to June 2020. Fourteen randomized controlled trials (N = 1831) evaluating effect of mindfulness in reducing anxiety and depression in cancer, measuring at pre-and-post interventions were included in this study. Random effects model was utilized for effect-size calculation. Interventions were between 5-8 weeks, with majority of participants been female (98.79%). Significant medium effect was observed for anxiety (g = 0.34) and depression (g = 0.32) with moderate heterogeneity and higher for mindfulness (g = 1.061) with high heterogeneity. Publication bias was not observed. Mindfulness has substantial effects in reducing anxiety and depression in cancer infected and survivors.

How To Kill A Greek God - A Review, Critique, and Meta-Analysis of 14 years of Proteus Effect Research

The Proteus Effect is a phenomenon whereby a user of a virtual environment temporarily adopts attitudes and behaviours that are consistent withstereotypes associated with the appearance of their avatar.A recent meta-analysis (Ratan et al, 2019) estimates that the strength of the Proteus Effect is "small to medium" under the de facto descriptors of Cohen (1992). Ratan et al also suggest some meta-analytic regressors which may moderate the overall effect. In this replication and extension of Ratan et al’s review, the conditions under which an effect should be observed are made explicit, and a number of potential issues with the previous review are highlighted and addressed. These include conflation of a number of different theories (Virtual Self Modelling, perspective taking), the erroneous inclusion and omission of studies, errors in effect size calculation, and the possible motivated selection of effects.Results reveal that although the Proteus Effect may be a robust effect with several demonstrative studies, the omnibus effect size of the Proteus Effect is smaller than previously indicated, is sensitive to the inclusion of negativeresults, and that the moderators suggested in the original meta-analysis do not significantly contribute to the prediction of the effect sizes.It is ultimately argued that the Proteus Effect ought not be embraced as an intervention and is more useful as an indicator of stereotype activations.Suggestions are made for a progressive research line which aims to unpack the Proteus Effect and increase the consistency and variety of predictions it can make, including ways to reduce the effect and allow controllers thefreedom to be who they want to be in virtual environments.

How to Kill a Greek God: A Meta-Analysis and Critical Review of 14 years of Proteus Effect Research

The Proteus Effect is a phenomenon whereby a user of a virtual environment temporarily adopts attitudes and behaviours that are consistent with stereotypes associated with the appearance of their avatar. A recent meta-analysis (Ratan et al, 2019) estimates that the strength of the Proteus Effect is \"small to medium\" under the de facto descriptors of Cohen (1992). Ratan et al also suggest some meta-analytic regressors which may moderate the overall effect. In this replication and extension of Ratan et al's review, the conditions under which an effect should be observed are made explicit, and a number of potential issues with the previous review are highlighted and addressed. These include conflation of a number of different theories (Virtual Self Modelling, perspective taking), the erroneous inclusion and omission of studies, errors in effect size calculation, and the possible motivated selection of effects. Results reveal that although the Proteus Effect may be a robust effect with several demonstrative studies, the omnibus effect size of the Proteus Effect is be smaller than previously indicated, is sensitive to the inclusion of negative results, and that the moderators suggested in the original meta-analysis do not significantly contribute to the prediction of the effect sizes. It is ultimately argued that the Proteus Effect ought not be embraced as an intervention and is more useful as an indicator of stereotype activations. Suggestions are made for a progressive research line which aims to unpack the Proteus Effect and increase the consistency and variety of predictions it can make, including ways to reduce the effect and allow controllers the freedom to be who they want to be in virtual environments.

Simulation-based study design accuracy weights are not generalisable and can still lead to biased meta-analytic inference: Comments on Christie et al. 2019

Variable study quality is a challenge for all the empirical sciences, but perhaps particularlyfor disciplines such as ecology where experimentation is frequently hampered by systemcomplexity, scale, and resourcing. The resulting heterogeneity, and the necessity ofsubsequently combining the results of different study designs, is a fundamental issue forevidence synthesis. We welcome the recognition of this issue by Christie et al. (2019), andtheir attempt to provide a generic approach to study quality assessment and meta-analyticweighting through an extensive simulation study. However, we have reservations about thetrue generality and usefulness of their derived study “accuracy weights”. First, the Christie etal. simulations rely on a single approach to effect size calculation, resulting in the oddconclusion that BACI designs are superior to RCTs, which are normally considered the goldstandard for causal inference. Second, so-called “study quality” scores have long beencriticised in the epidemiological literature for failing to accurately summarise individual,study-specific drivers of bias, and have been shown to be likely to retain bias and increasevariance relative to meta-regression approaches that explicitly model such drivers. Wesuggest that ecological meta-analysts spend more time critically, and transparently,appraising actual studies before synthesis, rather than relying on generic weights or weightingformulas to solve assumed issues; sensitivity analyses and hierarchical meta-regression arelikely to be key tools in this work.

Meta-Analysis: the Effect of Problem Approach and Inquiry Approach Toward Students’ Mathematical Critical Thinking Skill Over the Past 4 Years

Several studies have been conducted to improve the critical-thinking ability through various models, including problem approach and inquiry approach. The purpose of this study is to analyze which model is the most influential to improve students' critical-thinking skills in the last 4 years of research. This type of research is a mixed-method (quantitative-qualitative which, involved 230 students in the classroom with the problem approach and 263 students with the inquiry approach. The data collection technique used was the documentation of research reports. The data analysis used was meta-analysis through effect size calculation and Z-test. The result shows that the problem approach has a greater influence on students' critical thinking skills than the inquiry approach. This is indicated by the average values of the effect size and Z-test respectively 0.9685 and 83.122 for the problem approach and 0.7207 and 77.162 for the inquiry approach.

PEER TUTORING STRATEGY TO TEACH READING COMPREHENSION

This study was a quasi-experimental study. It was to find out the use of peer tutoring strategy and its significant effect to teach reading comprehension. The population of this research was the whole year-8 students of SMP NEGERI 2 Pontianak. Cluster random sampling was used to determine the sample. The samples were students of year-8 H as the experimental group and year-8 D as the control group. Measurement technique was employed in this research. The tool of collecting data was reading test and further analyzed by using SPSS software. The research result showed that peer tutoring strategy was effective to teach reading comprehension and Ho rejected since t value > ttable (5.081 > 2.0032). The result of the effect size calculation yielded a strong effect (1.237). In brief, it can be concluded that peer tutoring strategy had the strong effect in teaching reading comprehension of narrative text. It is suggested to be applied in teaching reading comprehension