Back to Basics with Mixed-Effects Models Bliese, Paul D.; Maltarich, Mark A.; Hendricks, Jonathan L.
Journal of business and psychology,
02/2018, Letnik:
33, Številka:
1
Journal Article
Recenzirano
Purpose
Multilevel mixed effects models are widely used in organizational behavior and organizational psychology to test and advance theory. At times, however, the complexity of the models leads ...researchers to draw erroneous inferences or otherwise use the models in less than optimal ways. We present nine take-away points intended to enhance the theoretical precision and utility of the models.
Approach
We demonstrate our points using two types of simulated data: one in which group membership is irrelevant, and the other in which relationships exist only because of group membership. We then demonstrate that the effects we observe in simulated data replicate in organizational data.
Findings
Little that we address will be new to methodology experts; nonetheless, we draw together a variety of points that we believe will help advance both theory and analytic rigor in multilevel analyses.
Implications
We make two points that run somewhat counter to conventional norms. First, we argue that mixed-effects models are appropriate even when ICC(1) values associated with the outcome data are small and non-significant. Second, we show that high ICC(2) values are not a prerequisite for detecting emergent multilevel relationships.
Originality/Value
The article is designed to be a resource for researchers who are learning about and applying mixed-effects (i.e., multilevel) models.
Intrahepatic cholangiocarcinoma (ICC) ranks as the second most malignant type of primary liver cancer with a high degree of incidence and a very poor prognosis. Fat mass and obesity-associated ...protein (FTO) functions as an eraser of the RNA m
A modification, but its roles in ICC tumorigenesis and development remain unknown. We showed here that the protein level of FTO was downregulated in clinical ICC samples and cell lines and that FTO expression was inversely correlated with the expression of CA19-9 and micro-vessel density (MVD). A Kaplan-Meier survival analysis showed that a low expression of
predicted poor prognosis in ICC.
, decreased endogenous expression of
obviously reduced apoptosis of ICC cells. Moreover,
suppressed the anchorage-independent growth and mobility of ICC cells. Through mining the database, FTO was found to regulate the integrin signaling pathway, inflammation signaling pathway, epidermal growth factor receptor (EGFR) signaling pathway, angiogenesis, and the pyrimidine metabolism pathway. RNA decay assay showed that oncogene
mRNA stability was impaired by FTO. In addition, the overexpression of FTO suppressed tumor growth
. In conclusion, our study demonstrated the critical roles of FTO in ICC.
After the International Cartographic Conference in Dresden held two years ago, the 27th International Cartographic Conference was held in Rio de Janeiro (Brazil) from August 23 to 28, 2015. The ...conference was organised by the Brazilian Society of Cartography and sponsored by the International Cartographic Association (ICA).
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Exposure to environmental phenols including parabens, bisphenols (BPs), oxybenzone/benzophenone-3 (BP-3) and triclosan (TCS) is ubiquitous. Due to evidence of their estrogenic activity, they have ...been considered as chemicals of concern. The exposure of the Norwegian population to these compounds is presently unknown.
To measure urinary levels of twelve different environmental phenols including four emerging bisphenols: S, F, B and AF (abbreviated as BPS, BPF, BPB and BPAF, respectively) in a healthy Norwegian population. We have calculated short-term variability, estimated daily intakes and investigated important determinants of exposure.
Urine samples were collected from mothers (n = 48) and their children (n = 56) during spring/summer 2012 in two counties in Norway.
Six environmental phenols namely methyl, ethyl and propyl paraben, BPA, BP-3 and TCS were detected in almost 100% of the urine samples. Among the emerging bisphenols, BPS was detected most frequently in the urine samples (42–48%) followed by BPF (4–15%). Parabens were positively and significantly correlated to each other in both mothers and children. Levels of parabens and BP-3 were higher in mothers compared to children. All mothers and children had lower estimated daily intakes (back calculated from the urinary concentrations) of parabens and BPA than the respective acceptable and tolerable daily intakes (ADIs and TDIs) established by the European Food Safety Authority (EFSA). Observed intraclass correlation coefficients (ICCs) indicated moderate to high reliability of spot urine measurements for all the environmental phenols (ICCs: 0.70–0.97). Use of hair products, deodorants, face and hand creams were significantly associated with higher urinary levels of parabens.
Occurrence of environmental phenols in healthy Norwegian women and children is abundant. Among emerging bisphenols, there is widespread exposure to BPS. A single spot urine sample can be used for estimating short-term exposures of environmental phenols. Urinary levels of parabens were associated with use of PCPs.
•Twelve environmental phenols were measured in Norwegian healthy mother-child pairs.•Most environmental phenols showed high ICCs within 24 h.•Emerging bisphenol like BPS was detected in about half of the urine samples.•Urinary levels of parabens were associated with use of personal care products.
Most existing mobile malware detection methods (e.g., Kirin and DroidMat) are designed based on the resources required by malwares (e.g., permissions, application programming interface (API) calls, ...and system calls). These methods capture the interactions between mobile apps and Android system, but ignore the communications among components within or cross application boundaries. As a consequence, the majority of the existing methods are less effective in identifying many typical malwares, which require a few or no suspicious resources, but leverage on inter-component communication (ICC) mechanism when launching stealthy attacks. To address this challenge, we propose a new malware detection method, named ICCDetector. ICCDetector outputs a detection model after training with a set of benign apps and a set of malwares, and employs the trained model for malware detection. The performance of ICCDetector is evaluated with 5264 malwares, and 12026 benign apps. Compared with our benchmark, which is a permission-based method proposed by Peng et al. in 2012 with an accuracy up to 88.2%, ICCDetector achieves an accuracy of 97.4%, roughly 10% higher than the benchmark, with a lower false positive rate of 0.67%, which is only about a half of the benchmark. After manually analyzing false positives, we discover 43 new malwares from the benign data set, and reduce the number of false positives to seven. More importantly, ICCDetector discovers 1708 more advanced malwares than the benchmark, while it misses 220 obvious malwares, which can be easily detected by the benchmark. For the detected malwares, ICCDetector further classifies them into five newly defined malware categories, which help understand the relationship between malicious behaviors and ICC characteristics. We also provide a systemic analysis of ICC patterns of benign apps and malwares.
This study reported the intercultural communicative competence (ICC) development of twenty-one Taiwanese English as a Foreign Language (EFL) college students who participated in a five-week ...Taiwan-New Zealand telecollaboration program, Kindling, in a multimodal online environment. To this end we investigated 1) the association between their oral translanguaging practices and development of ICC, and 2) aspects of intercultural learning that impacted their translanguaging experience. Data included recordings of group-based online communication and reflection notes on their online Quality Talk (QT) discussions, to which we applied content analysis based on ICC framework. The findings indicated that oral translanguaging facilitated students' development of positive attitudes toward intercultural awareness and learning. Analysis of the cultural comparisons and perspective shifts recorded in their QT reflection notes revealed ways in which students experienced dynamic aspects of intercultural learning through oral translanguaging. These results encourage researchers and practitioners to provide opportunities for language learners’ ICC development and intercultural learning through oral translanguaging opportunities in digitally mediated socialization through telecollaboration.
Intraclass correlation coefficients (ICC) are recommended for the assessment of the reliability of measurement scales. However, the ICC is subject to a variety of statistical assumptions such as ...normality and stable variance, which are rarely considered in health applications.
A Bayesian approach using hierarchical regression and variance-function modeling is proposed to estimate the ICC with emphasis on accounting for heterogeneous variances across a measurement scale. As an application, we review the implementation of using an ICC to evaluate the reliability of Observer OPTION
, an instrument which used trained raters to evaluate the level of Shared Decision Making between clinicians and patients. The study used two raters to evaluate recordings of 311 clinical encounters across three studies to evaluate the impact of using a Personal Decision Aid over usual care. We particularly focus on deriving an estimate for the ICC when multiple studies are being considered as part of the data.
The results demonstrate that ICC varies substantially across studies and patient-physician encounters within studies. Using the new framework we developed, the study-specific ICCs were estimated to be 0.821, 0.295, and 0.644. If the within- and between-encounter variances were assumed to be the same across studies, the estimated within-study ICC was 0.609. If heteroscedasticity is not properly adjusted for, the within-study ICC estimate was inflated to be as high as 0.640. Finally, if the data were pooled across studies without accounting for the variability between studies then ICC estimates were further inflated by approximately 0.02 while formerly allowing for between study variation in the ICC inflated its estimated value by approximately 0.066 to 0.072 depending on the model.
We demonstrated that misuse of the ICC statistics under common assumption violations leads to misleading and likely inflated estimates of interrater reliability. A statistical analysis that overcomes these violations by expanding the standard statistical model to account for them leads to estimates that are a better reflection of a measurement scale's reliability while maintaining ease of interpretation. Bayesian methods are particularly well suited to estimating the expanded statistical model.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To dissect the tumor ecosystem following immune checkpoint blockades (ICBs) in intrahepatic cholangiocarcinoma (ICC) at a single-cell level.
Single-cell RNA sequencing (scRNA-seq) data of 10 ICC ...patients for the ICB clinical trial were extracted from GSE125449 and systematically reanalyzed. Bulk RNA-seq data of 255 ICC patients were analyzed. Infiltration levels of SPP1
CD68
tumor-associated macrophages (TAMs) were examined by dual immunofluorescence (IF) staining in 264 resected ICC samples. The correlation between SPP1
TAMs and clinicopathological features as well as their prognostic significance was evaluated.
Among the 10 patients, five received biopsy at baseline, and others were biopsied at different timings following ICBs. Single-cell transcriptomes for 5,931 cells were obtained. A tighter cellular communication network was observed in ICB-treated ICC. We found a newly emerging VEGF signaling mediated by PGF-VEGFR1 between cancer-associated fibroblasts (CAFs) and endothelial cells in ICC following ICBs. SPP1 expression was dramatically upregulated, and SPP1
TAM gene signatures were enriched in TAMs receiving ICB therapy. We also identified SPP1
TAMs as an independent adverse prognostic indicator for survival in ICC.
Our analyses provide an overview of the altered tumor ecosystem in ICC treated with ICBs and highlight the potential role of targeting CAFs and SPP1
TAMs in developing a more rational checkpoint blockade-based therapy for ICC.
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