scholarly journals Tail asymptotic behavior of the supremum of a class of chi-square processes

2019 ◽  
Vol 154 ◽  
pp. 108551 ◽  
Author(s):  
Lanpeng Ji ◽  
Peng Liu ◽  
Stephan Robert
2020 ◽  
Vol 24 ◽  
pp. 435-453
Author(s):  
Mickael Albertus

The raking-ratio method is a statistical and computational method which adjusts the empirical measure to match the true probability of sets of a finite partition. The asymptotic behavior of the raking-ratio empirical process indexed by a class of functions is studied when the auxiliary information is given by estimates. These estimates are supposed to result from the learning of the probability of sets of partitions from another sample larger than the sample of the statistician, as in the case of two-stage sampling surveys. Under some metric entropy hypothesis and conditions on the size of the information source sample, the strong approximation of this process and in particular the weak convergence are established. Under these conditions, the asymptotic behavior of the new process is the same as the classical raking-ratio empirical process. Some possible statistical applications of these results are also given, like the strengthening of the Z-test and the chi-square goodness of fit test.


Mathematics ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 129
Author(s):  
Árpád Baricz ◽  
Dragana Jankov Maširević ◽  
Tibor K. Pogány

The cumulative distribution function of the non-central chi-square distribution χn′2(λ) of n degrees of freedom possesses an integral representation. Here we rewrite this integral in terms of a lower incomplete gamma function applying two of the second mean-value theorems for definite integrals, which are of Bonnet type and Okamura’s variant of the du Bois–Reymond theorem. Related results are exposed concerning the small argument cases in cumulative distribution function (CDF) and their asymptotic behavior near the origin.


2007 ◽  
Vol 44 (02) ◽  
pp. 285-294 ◽  
Author(s):  
Qihe Tang

We study the tail behavior of discounted aggregate claims in a continuous-time renewal model. For the case of Pareto-type claims, we establish a tail asymptotic formula, which holds uniformly in time.


2020 ◽  
Vol 63 (6) ◽  
pp. 2016-2026
Author(s):  
Tamara R. Almeida ◽  
Clayton H. Rocha ◽  
Camila M. Rabelo ◽  
Raquel F. Gomes ◽  
Ivone F. Neves-Lobo ◽  
...  

Purpose The aims of this study were to characterize hearing symptoms, habits, and sound pressure levels (SPLs) of personal audio system (PAS) used by young adults; estimate the risk of developing hearing loss and assess whether instructions given to users led to behavioral changes; and propose recommendations for PAS users. Method A cross-sectional study was performed in 50 subjects with normal hearing. Procedures included questionnaire and measurement of PAS SPLs (real ear and manikin) through the users' own headphones and devices while they listened to four songs. After 1 year, 30 subjects answered questions about their usage habits. For the statistical analysis, one-way analysis of variance, Tukey's post hoc test, Lin and Spearman coefficients, the chi-square test, and logistic regression were used. Results Most subjects listened to music every day, usually in noisy environments. Sixty percent of the subjects reported hearing symptoms after using a PAS. Substantial variability in the equivalent music listening level (Leq) was noted ( M = 84.7 dBA; min = 65.1 dBA, max = 97.5 dBA). A significant difference was found only in the 4-kHz band when comparing the real-ear and manikin techniques. Based on the Leq, 38% of the individuals exceeded the maximum daily time allowance. Comparison of the subjects according to the maximum allowed daily exposure time revealed a higher number of hearing complaints from people with greater exposure. After 1 year, 43% of the subjects reduced their usage time, and 70% reduced the volume. A volume not exceeding 80% was recommended, and at this volume, the maximum usage time should be 160 min. Conclusions The habit of listening to music at high intensities on a daily basis seems to cause hearing symptoms, even in individuals with normal hearing. The real-ear and manikin techniques produced similar results. Providing instructions on this topic combined with measuring PAS SPLs may be an appropriate strategy for raising the awareness of people who are at risk. Supplemental Material https://doi.org/10.23641/asha.12431435


Crisis ◽  
2015 ◽  
Vol 36 (6) ◽  
pp. 416-423 ◽  
Author(s):  
Richard Shadick ◽  
Faedra Backus Dagirmanjian ◽  
Baptiste Barbot

Abstract. Background: Research on young adults in the general population has identified a relationship between sexual minority identification and risk for suicide. Differential rates of suicidal ideation and attempts have also been found across racial and ethnic groups. Aims: This study examined risk for suicide among university students, based on membership in one or more marginalized groups (sexual minority and racial minority identification). Method: Data were collected from first-year college students (N = 4,345) at an urban university. Structural equation modeling was employed to model a suicidality construct, based on which a "risk for suicide" category system was derived. Chi-square and logistic regression analyses were then conducted to estimate the relationship between the background variables of interest and suicide risk. Results: Students who identified as lesbian, gay, or bisexual (LGB) were associated with higher suicide risk than their heterosexual peers. Students of color were slightly less at risk than their heterosexual peers. However, LGB students of color were associated with elevated suicide risk relative to heterosexual peers. Conclusion: Results indicate that belonging to multiple marginalized groups may increase one's risk for suicide, though these effects are not simply additive. Findings highlight the complexity of the intersection between marginalized identities and suicidality.


Author(s):  
Sandrine Roussel ◽  
Alain Deccache ◽  
Mariane Frenay

Introduction: The implementation of Therapeutic Patient Education (TPE) remains a challenge. An exploratory study highlighted two tendencies among practitioners of TPE, which could hamper this implementation: an oscillation between identities (as caregivers versus as educators) and an inclination towards subjective psychological health objectives. Objectives: To verify whether these tendencies can be observed among an informed audience in TPE. Next, to explore the variables associated with one or other of these tendencies. Method: A quantitative cross-sectional survey by a self-administered questionnaire was carried out among 90 French-speaking healthcare professionals. Statistical analyses (chi-square, logistic regression) were then conducted. Results: Sixty percent of respondents displayed identity oscillation, which was found to be linked to task oscillation, patient curability, scepticism towards medicine and practising in France. Fifty-six percent pursued subjective psychological health objectives, which was found to be associated with health behaviour objectives and a locus of power in the healthcare relationship distinct from those seen in the pre-existing health models (biomedical, global). This tendency seems to constitute an alternative model of TPE. Discussion & conclusion: Identity oscillation and subjective psychological health objectives can be both observed. This study stresses the need to deliberate on the form(s) of TPE that is/are desired.


1993 ◽  
Vol 70 (03) ◽  
pp. 393-396 ◽  
Author(s):  
Mandeep S Dhami ◽  
Robert D Bona ◽  
John A Calogero ◽  
Richard M Hellman

SummaryA retrospective study was done to determine the incidence of and the risk factors predisposing to clinical venous thromboembolism (VTE) in patients treated for high grade gliomas. Medical records of 68 consecutive patients diagnosed and treated at Saint Francis Hospital and Medical Center from January 1986 to June 1991 were reviewed. The follow up was to time of death or at least 6 months (up to December 1991). All clinically suspected episodes of VTE were confirmed by objective tests. Sixteen episodes of VTE were detected in 13 patients for an overall episode rate of 23.5%. Administration of chemotherapy (p = 0.027, two tailed Fisher exact test) and presence of paresis (p = 0.031, two tailed Fisher exact test) were statistically significant risk factors for the development of VTE. Thrombotic events were more likely to occur in the paretic limb and this difference was statistically significant (p = 0.00049, chi square test, with Yates correction). No major bleeding complications were seen in the nine episodes treated with long term anticoagulation.We conclude that venous thromboembolic complications are frequently encountered in patients being treated for high grade gliomas and the presence of paresis and the administration of chemotherapy increases the risk of such complications.


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