13 research outputs found

    Power of the \u3cem\u3et\u3c/em\u3e Test for Normal and Mixed Normal Distributions

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    Previous research suggests that the power of the independent-samples t test decreases when population distributions are mixed normal rather than normal, and that robust methods have superior power under these conditions. However, under some conditions, the power for the independent-samples t test can be greater when the population distributions for the independent groups are mixed normal rather than normal. The implications of these results are discussed

    Performance of Nonparametric Person-Fit Statistics with Unfolding versus Dominance Response Models

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    Person-fit analyses are commonly used to detect aberrant responding in self-report data. Nonparametric person fit statistics do not require fitting a parametric test theory model and have performed well compared to other person-fit statistics. However, detection of aberrant responding has primarily focused on dominance response data, thus the effectiveness of person-fit statistics in detecting different aberrant behaviors in ideal point data is unclear. This study compares the performance of nonparametric person-fit statistics in unfolding and dominance model contexts. Results for dominance data indicate that increases in detection rates depend, among other factors, on type of aberrant responding and person-fit statistic used. The detection of aberrant responses in ideal point data was ineffective using four nonparametric person-fit statistics, with slightly higher type I error and power less than 0.25. Additional research is needed to identify or develop nonparametric or parametric person-fit statistics effective for aberrant behavior exhibited in ideal point data

    The Effects of Aberrant Responding on Model-Fit Assuming Different Underlying Response Processes

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    Aberrant responding on tests and surveys has been shown to affect the psychometric properties of scales and the statistical analyses from the use of those scales in cumulative model contexts. This study extends prior research by comparing the effects of four types of aberrant responding on model fit in both cumulative and ideal point model contexts using graded partial credit (GPCM) and generalized graded unfolding (GGUM) models. When fitting models to data, model misfit can be both a function of misspecification and aberrant responding. Results demonstrate how varying levels of aberrant data can severely impact model fit for both cumulative and ideal-point data. Specifically, longstring responses have a stronger impact on dimensionality for both ideal point and cumulative data, while random responding tends to have the most negative impact on data model fit according to information criteria (AIC, BIC). The results also indicate that ideal point data models such as GGUM may be able to fit cumulative data as well as the cumulative model itself (GPCM), whereas cumulative data models may not provide sufficient model fit for data simulated using an ideal point model

    Are women’s orgasms hindered by phallocentric imperatives?

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    Women who have sex with women (WSW) are more likely to report experiencing an orgasm during partnered sex, compared to women who have sex with men (WSM). We investigated whether this difference can be partially accounted for by phallocentric imperatives—gendered sexual scripts that prioritize men’s sexual experience. For example, these imperatives emphasize vaginal-penile intercourse (i.e., the coital imperative) and men’s physical pleasure (i.e., the male orgasm imperative). We reasoned that a larger variety of sexual behaviors indicates less adherence to the coital imperative and that more self-oriented orgasm goals for women indicate less adherence to the male orgasm imperative. Consistent with previous work, we expected WSW to report higher rates of orgasm than WSM when taking frequency of sex into account. We also hypothesized that this difference in orgasm rates would dissipate when controlling for variety of sexual behavior and women’s self-oriented orgasm goals. In a sample of 1988 WSM and 308 WSW, we found that WSW were 1.33 times (p < .001) more likely to report experiencing an orgasm than WSM, controlling for frequency of sex. This incidence rate ratio was reduced to 1.16 (p < .001) after taking into account variety of sexual behavior and self-oriented orgasm goals. Our findings indicate that certain sexual scripts (e.g., phallocentric imperatives) help explain the orgasm discrepancy between WSW and WSM. We discuss masturbation as another male-centered practice that may be relevant to this gap, as well as implications for intervention and future research

    Multi-Sensory Cognitive Learning as Facilitated in a Multimedia Tutorial for Item Response Theory

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    The objective of this paper is to introduce an application of multi-sensory cognitive learning theory into the development of a multimedia tutorial for Item Response Theory. The cognitive multimedia theory suggests that the visual and auditory material should be presented simultaneously to reinforce the retention of learned materials. A computer-assisted module is carefully designed based upon the preceding theory and also an experiment was conducted to examine the effect of audio types (human audio, computer audio, and no audio) on learner performance measured by an objective test. It was found that while there is no significant performance gap between the human audio and the no audio group, the two groups substantively outperform the computer audio group. A plausible explanation is that un-natural audio requires additional cognitive power to process the information and thus this distraction affects the performance

    Assessing rigid modes of thinking in self-declared abortion ideology:natural language processing insights from an online pilot qualitative study on abortion attitudes

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    INTRODUCTION: Although much work has been done on US abortion ideology, less is known relative to the psychological processes that distinguish personal abortion beliefs or how those beliefs are communicated to others. As part of a forthcoming probability-based sampling designed study on US abortion climate, we piloted a study with a controlled sample to determine whether psychological indicators guiding abortion beliefs can be meaningfully extracted from qualitative interviews using natural language processing (NLP) substring matching. Of particular interest to this study is the presence of cognitive distortions-markers of rigid thinking-spoken during interviews and how cognitive distortion frequency may be tied to rigid, or firm, abortion beliefs. METHODS: We ran qualitative interview transcripts against two lexicons. The first lexicon, the cognitive distortion schemata (CDS), was applied to identify cognitive distortion n-grams (a series of words) embedded within the qualitative interviews. The second lexicon, the Linguistic Inquiry Word Count (LIWC), was applied to extract other psychological indicators, including the degrees of (1) analytic thinking, (2) emotional reasoning, (3) authenticity, and (4) clout. RESULTS: People with polarized abortion views (i.e., strongly supportive of or opposed to abortion) had the highest observed usage of CDS n-grams, scored highest on authenticity, and lowest on analytic thinking. By contrast, people with moderate or uncertain abortion views (i.e., people holding more complex or nuanced views of abortion) spoke with the least CDS n-grams and scored slightly higher on analytic thinking. DISCUSSION AND CONCLUSION: Our findings suggest people communicate about abortion differently depending on their personal abortion ideology. Those with strong abortion views may be more likely to communicate with authoritative words and patterns of words indicative of cognitive distortions-or limited complexity in belief systems. Those with moderate views are more likely to speak in conflicting terms and patterns of words that are flexible and open to change-or high complexity in belief systems. These findings suggest it is possible to extract psychological indicators with NLP from qualitative interviews about abortion. Findings from this study will help refine our protocol ahead of full-study launch

    Hepatic alterations during the development and progression of cancer cachexia

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    Cancer associated bodyweight loss (cachexia) is a hallmark of many cancers and is associated with decreased quality of life and increased mortality. Hepatic function can dramatically influence whole body energy expenditure and may therefore significantly influence whole body health during cancer progression. PURPOSE: To examine alterations in markers of hepatic metabolism and physiology during cachexia progression. METHODS: Male C57BL/6J mice were injected with 1X106 Lewis Lung Carcinoma (LLC) cells dissolved in 100 L PBS and cancer was allowed to develop for 1, 2, 3, or 4 weeks. Control animals were injected with an equal volume of PBS. Livers were analyzed for measures of metabolism, collagen deposition, protein turnover and mitochondrial quality. RESULTS: 4wk animals had ~30% larger livers compared to all other groups. Cancer progression was associated with altered regulators of fat metabolism. Additionally, longer duration of cancer development was associated with ~3-fold increased regulators of collagen deposition as well as phenotypic collagen content, suggesting increased liver fibrosis. Mitochondrial quality control regulators appeared to be altered before any phenotypic alterations to collagen deposition. While induction of Akt was noted, downstream markers of protein synthesis were not altered. CONCLUSIONS: Cancer cachexia progression is associated with hepatic pathologies, specifically liver fibrosis. Alterations to mitochondrial quality control mechanisms appear to precede this fibrotic phenotype, potentially suggesting mitochondrial mechanisms for the development of hepatic pathologies during the development and progression of cancer cachexia. Novelty - Cachexia progression results in liver collagen deposition and fibrosis. - Alterations in mitochondrial quality control may precede liver pathologies during cachexia.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

    Rapid HPLC Quantification Approach for Detection of Active Constituents in Modern Combinatorial Formula, San-Huang-Xie-Xin-Tang (SHXXT)

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    San-Huang-Xie-Xin-Tang (SHXXT), one of the most important traditional Chinese medicinal formulas, is comprised by three herbal medicines, the rhizome of Rheum officinale [or R. tanguticum (Polygonaceae) (Dahuang in Chinese)], the root of Scutellaria baicalensis (Labiatae) (Huangqin in Chinese), and the rhizome of Coptis chinensis (Ranunculaceae) (Huanglian in Chinese) in the ratios of 2:1:1 or 1:1:1. This study is aimed to quantitate and qualify of SHXXT, by a rapid, convenient, and effective HPLC-PDA approach associated with LC-MS technique. Of which method, nine chosen major bioactive components in SHXXT, including aloe-emodin (Ale), baicalin (Ba), berberine (Be), coptisine (Co), palmatine (Pa), resveratroloside (Res), rhein (Rh), sennoside A (Se-A), and wogonin (Wo), were evaluated within 30 minutes. The nine chemical markers were monitored in a high sensitivity with a low detection limit of 0.01‒0.55 μg/mL and the correlation coefficient of the regression curve revealed a good linearity with R2 > 0.99. Moreover, the extraction solution system and the HPLC elution conditions were also optimized in the present study. This present developed protocol was then successfully applied to quantify nine chemical markers of ten SHXXT products from eight Taiwanese TCM pharmaceutical companies. In quantitative results, Res was found as the major compound in SHXXT-1~5 & 8 with significantly higher amounts than those in other products, indicating the products SHXXT-1~5 & 8 may use R. tanguticum as the raw material, which possessed a higher concentration of the bioactive composition Res, instead of R. officinale. Simultaneously, Ale, Rh, and Wo were less than 2% in these ten products. Different chemical profiles of commercial products indicated that, probably, each product with the same named formula might be regarded as a sole medicine and need to be investigated individually. Importantly, it is never too much to emphasize the importance of quality control in TCM development
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