A Simple Asymptotic Analysis of Residual-Based Statistics

What s the asymptotic null distribution of a rank-based serial autocorrelation test applied to residuals of an estimated GARCH model?What s the limiting distribution of estimated ACD parameters applied to the residuals of some first-stage modelling procedure?This paper addresses the often occurring situation in econometrics of applying standard statistics to residuals instead of innovations.The paper provides a simple and unified way of calculating the necessary adjustment in the limiting distribution, be it of tests or estimators. On the technical side, we also provide a novel approach to this problem using Le Cam s theory of convergence of experiments (in this paper restricted to Gaussian shift experiments).The resulting formula is simple and the regularity conditions required fairly minimal.Numerous examples show the strength and wide applicability of our approach.statistics;estimation;ranking

A Simple Asymptotic Analysis of Residual-Based Statistics

What s the asymptotic null distribution of a rank-based serial autocorrelation test applied to residuals of an estimated GARCH model?What s the limiting distribution of estimated ACD parameters applied to the residuals of some first-stage modelling procedure?This paper addresses the often occurring situation in econometrics of applying standard statistics to residuals instead of innovations.The paper provides a simple and unified way of calculating the necessary adjustment in the limiting distribution, be it of tests or estimators. On the technical side, we also provide a novel approach to this problem using Le Cam s theory of convergence of experiments (in this paper restricted to Gaussian shift experiments).The resulting formula is simple and the regularity conditions required fairly minimal.Numerous examples show the strength and wide applicability of our approach.

Stochatic Volatility Models with Transaction Time Risk

stochastic processes;volatility;models;transaction costs

GARCH and Irregularly Spaced Data

An exact discretization of continuous time stochastic volatility processes observed at irregularly spaced times is used to give insights on how a coherent GARCH model can be specified for such data. The relation of our approach with those in the existing literature is studied

Satisfaction with cosmetic outcomes of breast reconstruction:Investigations into the correlation between the patients' Breast-Q outcome and the judgment of panels

Objectives: We aimed to determine the relation between breast reconstruction method, patient satisfaction, and surgeon reported cosmetic outcome among women who underwent breast reconstruction after mastectomy. Study Design: A cross-sectional study of patients treated between 2006 and 2010. Main Outcome: Women's satisfaction with cosmetic outcomes after breast reconstruction. Measures: Cosmetic outcomes were evaluated by (1) women using the Breast-Q to rate satisfaction with breasts outcomes, and (2) an independent panel using the Strasser score. The relationships between the Breast-Q rating, Strasser scores, and breast reconstruction methods, including laterality and timing, were evaluated by Mann-Whitney U tests, Spearman's rank correlations, and Wilcoxon signed-rank tests. Results: Ninety-four women were included. Patients were more satisfied with their breasts if they had undergone autologous, unilateral, or secondary breast reconstruction compared with those who underwent alloplastic, bilateral, or primary breast reconstruction (p-values 0.008, 0.011, and 0.001, respectively). The Strasser system did not reveal significant cosmetic differences, with all breast reconstructions graded as mediocre or poor. Conclusions: Patient satisfaction with breast outcomes, as measured by the Breast-Q, was described as mediocre or poorly reflected by the Strasser score. If doctors are to support patients to make informed decisions on the optimal method of breast reconstruction, we need a more sensitive, comprehensive tool reflecting patients' cosmetic outcomes

Associations Between Clinician-Graded Facial Function and Patient-Reported Quality of Life in Adults With Peripheral Facial Palsy A Systematic Review and Meta-analysis:A Systematic Review and Meta-analysis

IMPORTANCE Understanding how the quality of life of adults (>= 18 years) with peripheral facial palsy can be estimated using clinician measures of facial function and patient-reported variables might aid in counseling patients and in conducting research. OBJECTIVES To analyze associations between clinician-graded facial function and patient-reported quality of life in adults with peripheral facial palsy, compare associations between facial function and the physical and social functions of quality of life, and examine factors that might influence the associations. DATA SOURCES A literature search was conducted in PubMed, Embase, CINAHL, Web of Science and PsycInfo on June 4, 2020, with no restrictions on the start date. STUDY SELECTION Twenty-three studies reporting an association between clinician-graded facial function and patient-reported quality of life in adults with peripheral facial palsy were included. Facial function instruments included the House-Brackmann, Sunnybrook Facial Grading System, and electronic clinician-graded facial function assessment. Quality-of-life instruments included the Facial Disability Index and Facial Clinimetric Evaluation Scale. DATA EXTRACTION AND SYNTHESIS Data extraction and qualitative synthesis were performed according to the Meta-analysis of Observational Studies in Epidemiology guidelines. Record screening, data extraction, and quality assessments were done by 2 researchers independently. Data were pooled using random-effects models. MAIN OUTCOMES AND MEASURES The main outcome was the association between facial function and quality of life, quantified by Pearson r, Spearman rho, or regression analysis. RESULTS In total, 23 studies (3746 participants) were included. In the 21 studies that reported on the sex of the cohorts, there were 2073 women (57.3%). Mean or median age ranged from 21 to 64 years and mean or median duration of palsy ranged from newly diagnosed to 12 years. Bell palsy (n = 1397), benign tumor (n = 980), and infection (n = 257) were the most common etiologic factors. Pooled correlation coefficients were 0.424 (95% CI, 0.375-0.471) to 0.533 (95% CI, 0.447-0.610) between facial function and Facial Clinimetric Evaluation Scale total, 0.324 (95% CI, 0.128-0.495) to 0.397 (95% CI, 0.242-0.532) between facial function and Facial Clinimetric Evaluation Scale social function, 0.423 (95% CI, 0.322-0.514) to 0.605 (95% CI, -0.124-0.910) between facial function and Facial Disability Index physical function, and 0.166 (95% CI, 0.044-0.283) to 0.208 (95% CI, 0.031-0.373) between facial function and Facial Disability Index social function. CONCLUSIONS AND RELEVANCE Associations noted in this systematic review and meta-analysis were overall low to moderate, suggesting that only a small part of quality of life is explained by facial function. Associations were higher between facial function and physical function than social function of quality of life