scholarly journals On Null Hypotheses and Heteroskedasticity

2021 ◽  
Author(s):  
Jeffery Sauer ◽  
Taylor M. Oshan ◽  
Sergio Rey ◽  
Levi John Wolf

Bivand and Wong (2018), a recent review on spatial statistical software, noted important differences in the results of the local Moran’s Ii statistic depending on the method of inference. That review speculated the differences may be due to the presence of local spatial heterogeneity. In this paper we design an experiment to assess the impact of local heterogeneity on hypothesis testing for local statistics. In this experiment, we analyze the relationship between measures of local variance, such as the local spatial heteroskedasticity (LOSH) statistic, and components of the local Moran’s Ii statistic. We consider this experiment with controlled synthetic heteroskedastic data and with uncontrolled real world data. We show that in both situations the variance components of the local Moran’s Ii statistic demonstrate a varying correlation with alternative measures of local variance like LOSH. In addition, we resituate the available inferential methods and suggest an alternative explanation for the differences observed in Bivand and Wong 2018. Ultimately, this paper demonstrates that there are important conceptual and computational differences as to what constituents a null hypothesis in local testing frameworks. Therefore, researchers must be aware as to how their choices may shape the observed spatial patterns.

1989 ◽  
Vol 171 (2) ◽  
pp. 57-74 ◽  
Author(s):  
Terence O'connor

Current approaches to multicultural education tend to ignore the cultural politics of educational relationships that rest at the heart of intercultural encounters. This essay uses the concept of “voice” to describe how individuals orient themselves to school discourses. The idea of “cultural voice” is developed to explain how the dynamics of culture groups reveal the critical relationship between the reconstruction of cultural principles and the development of the individual. This alternative explanation of the relationship between school discourse and cultural voice reinterprets the cultural politics of educational discourses and reassesses the impact of racism, sexism, and classism. From this discussion, the essay draws out a framework for multicultural education which focuses on the politics of educational relationships in pluralistic societies. It sketches out several teaching suggestions for a multivoiced, democratic, multicultural education that can counter cultural biases in schools.


2008 ◽  
Vol 58 (2) ◽  
pp. 185-199 ◽  
Author(s):  
I. Agárdi ◽  
A. Bauer

Prior research suggests that alliances created between retailers provide numerous benefits for their members which result in higher retail performance. The paper investigates whether the size of a firm is a moderating variable and/or an alternative explanation in studying the effect of alliance membership on the retailer’s performance. An empirical study, based on a small-scale survey, was carried out among 99 small-and medium-sized retailers in Hungary. Not only the strength but also the form of the relationship between alliance membership, performance and firm size have been investigated. Findings of the research support that firm size changes the form of causal relationship between alliance and performance of a retailer. Size contributes substantially to the variation of retail performance and increases the impact of alliance membership on sales and profit growth of retailers.


Author(s):  
Brynne D. Ovalle ◽  
Rahul Chakraborty

This article has two purposes: (a) to examine the relationship between intercultural power relations and the widespread practice of accent discrimination and (b) to underscore the ramifications of accent discrimination both for the individual and for global society as a whole. First, authors review social theory regarding language and group identity construction, and then go on to integrate more current studies linking accent bias to sociocultural variables. Authors discuss three examples of intercultural accent discrimination in order to illustrate how this link manifests itself in the broader context of international relations (i.e., how accent discrimination is generated in situations of unequal power) and, using a review of current research, assess the consequences of accent discrimination for the individual. Finally, the article highlights the impact that linguistic discrimination is having on linguistic diversity globally, partially using data from the United Nations Educational, Scientific and Cultural Organization (UNESCO) and partially by offering a potential context for interpreting the emergence of practices that seek to reduce or modify speaker accents.


2010 ◽  
Vol 20 (1) ◽  
pp. 3-8
Author(s):  
Dee Adams Nikjeh

Abstract Administrators and supervisors face daily challenges over issues such as program funding, service fees, correct coding procedures, and the ever-changing healthcare regulations. Receiving equitable reimbursement for speech-language pathology and audiology services necessitates an understanding of federal coding and reimbursement systems. This tutorial provides information pertaining to two major healthcare coding systems and explains the relationship of these systems to clinical documentation, the Medicare Physician Fee Schedule and equitable reimbursement. An explanation of coding edits and coding modifiers is provided for use in those occasional atypical situations when the standard use of procedural coding may not be appropriate. Also included in this tutorial is a brief discussion of the impact that the Medicare Improvements for Patients and Providers Act of 2008 (HR 6331 Medicare Improvements for Patients and Providers Act [MIPPA], 2008) has had on the valuation of speech-language pathology procedure codes.


2014 ◽  
Vol 22 (4) ◽  
pp. 194-201 ◽  
Author(s):  
Freda-Marie Hartung ◽  
Britta Renner

Humans are social animals; consequently, a lack of social ties affects individuals’ health negatively. However, the desire to belong differs between individuals, raising the question of whether individual differences in the need to belong moderate the impact of perceived social isolation on health. In the present study, 77 first-year university students rated their loneliness and health every 6 weeks for 18 weeks. Individual differences in the need to belong were found to moderate the relationship between loneliness and current health state. Specifically, lonely students with a high need to belong reported more days of illness than those with a low need to belong. In contrast, the strength of the need to belong had no effect on students who did not feel lonely. Thus, people who have a strong need to belong appear to suffer from loneliness and become ill more often, whereas people with a weak need to belong appear to stand loneliness better and are comparatively healthy. The study implies that social isolation does not impact all individuals identically; instead, the fit between the social situation and an individual’s need appears to be crucial for an individual’s functioning.


Crisis ◽  
2016 ◽  
Vol 37 (4) ◽  
pp. 265-270 ◽  
Author(s):  
Meshan Lehmann ◽  
Matthew R. Hilimire ◽  
Lawrence H. Yang ◽  
Bruce G. Link ◽  
Jordan E. DeVylder

Abstract. Background: Self-esteem is a major contributor to risk for repeated suicide attempts. Prior research has shown that awareness of stigma is associated with reduced self-esteem among people with mental illness. No prior studies have examined the association between self-esteem and stereotype awareness among individuals with past suicide attempts. Aims: To understand the relationship between stereotype awareness and self-esteem among young adults who have and have not attempted suicide. Method: Computerized surveys were administered to college students (N = 637). Linear regression analyses were used to test associations between self-esteem and stereotype awareness, attempt history, and their interaction. Results: There was a significant stereotype awareness by attempt interaction (β = –.74, p = .006) in the regression analysis. The interaction was explained by a stronger negative association between stereotype awareness and self-esteem among individuals with past suicide attempts (β = –.50, p = .013) compared with those without attempts (β = –.09, p = .037). Conclusion: Stigma is associated with lower self-esteem within this high-functioning sample of young adults with histories of suicide attempts. Alleviating the impact of stigma at the individual (clinical) or community (public health) levels may improve self-esteem among this high-risk population, which could potentially influence subsequent suicide risk.


Crisis ◽  
2010 ◽  
Vol 31 (4) ◽  
pp. 217-223 ◽  
Author(s):  
Paul Yip ◽  
David Pitt ◽  
Yan Wang ◽  
Xueyuan Wu ◽  
Ray Watson ◽  
...  

Background: We study the impact of suicide-exclusion periods, common in life insurance policies in Australia, on suicide and accidental death rates for life-insured individuals. If a life-insured individual dies by suicide during the period of suicide exclusion, commonly 13 months, the sum insured is not paid. Aims: We examine whether a suicide-exclusion period affects the timing of suicides. We also analyze whether accidental deaths are more prevalent during the suicide-exclusion period as life-insured individuals disguise their death by suicide. We assess the relationship between the insured sum and suicidal death rates. Methods: Crude and age-standardized rates of suicide, accidental death, and overall death, split by duration since the insured first bought their insurance policy, were computed. Results: There were significantly fewer suicides and no significant spike in the number of accidental deaths in the exclusion period for Australian life insurance data. More suicides, however, were detected for the first 2 years after the exclusion period. Higher insured sums are associated with higher rates of suicide. Conclusions: Adverse selection in Australian life insurance is exacerbated by including a suicide-exclusion period. Extension of the suicide-exclusion period to 3 years may prevent some “insurance-induced” suicides – a rationale for this conclusion is given.


Sign in / Sign up

Export Citation Format

Share Document